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gerrit-public.fairphone.software / platform / docs / source.android.com / 5819eeefa9cfafa892d4ab18adb41857b4692b35 / . / src / compatibility / 6.0 / android-6.0-cdd.html
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2<head>
3<title>Android 6.0 Compatibility Definition</title>
4<link rel="stylesheet" type="text/css" href="source/android-cdd.css"/>
5</head>
6
7<body>
8
9<h6>Table of Contents</h6>
10
11<div id="toc">
12
13<div id="toc_left">
14
15<p class="toc_h1"><a href="#1_introduction">1. Introduction</a></p>
16
17<p class="toc_h1"><a href="#2_device_types">2. Device Types</a></p>
18
19<p class="toc_h2"><a href="#2_1_device_configurations">2.1 Device Configurations</a></p>
20
21<p class="toc_h1"><a href="#3_software">3. Software</a></p>
22
23<p class="toc_h2"><a href="#3_1_managed_api_compatibility">3.1. Managed API Compatibility</a></p>
24
25<p class="toc_h2"><a href="#3_2_soft_api_compatibility">3.2. Soft API Compatibility</a></p>
26
27<p class="toc_h3"><a href="#3_2_1_permissions">3.2.1. Permissions</a></p>
28
29<p class="toc_h3"><a href="#3_2_2_build_parameters">3.2.2. Build Parameters</a></p>
30
31<p class="toc_h3"><a href="#3_2_3_intent_compatibility">3.2.3. Intent Compatibility</a></p>
32
33<p class="toc_h4"><a href="#3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</a></p>
34
35<p class="toc_h4"><a href="#3_2_3_2_intent_resolution">3.2.3.2. Intent Resolution</a></p>
36
37<p class="toc_h4"><a href="#3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</a></p>
38
39<p class="toc_h4"><a href="#3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</a></p>
40
41<p class="toc_h4"><a href="#3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</a></p>
42
43<p class="toc_h2"><a href="#3_3_native_api_compatibility">3.3. Native API Compatibility</a></p>
44
45<p class="toc_h3"><a href="#3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</a></p>
46
47<p class="toc_h3"><a href="#3_3_2_32-bit_arm_native_code_compatibility">3.3.2. 32-bit ARM Native Code Compatibility</a></p>
48
49<p class="toc_h2"><a href="#3_4_web_compatibility">3.4. Web Compatibility</a></p>
50
51<p class="toc_h3"><a href="#3_4_1_webview_compatibility">3.4.1. WebView Compatibility</a></p>
52
53<p class="toc_h3"><a href="#3_4_2_browser_compatibility">3.4.2. Browser Compatibility</a></p>
54
55<p class="toc_h2"><a href="#3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</a></p>
56
57<p class="toc_h2"><a href="#3_6_api_namespaces">3.6. API Namespaces</a></p>
58
59<p class="toc_h2"><a href="#3_7_runtime_compatibility">3.7. Runtime Compatibility</a></p>
60
61<p class="toc_h2"><a href="#3_8_user_interface_compatibility">3.8. User Interface Compatibility</a></p>
62
63<p class="toc_h3"><a href="#3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</a></p>
64
65<p class="toc_h3"><a href="#3_8_2_widgets">3.8.2. Widgets</a></p>
66
67<p class="toc_h3"><a href="#3_8_3_notifications">3.8.3. Notifications</a></p>
68
69<p class="toc_h3"><a href="#3_8_4_search">3.8.4. Search</a></p>
70
71<p class="toc_h3"><a href="#3_8_5_toasts">3.8.5. Toasts</a></p>
72
73<p class="toc_h3"><a href="#3_8_6_themes">3.8.6. Themes</a></p>
74
75<p class="toc_h3"><a href="#3_8_7_live_wallpapers">3.8.7. Live Wallpapers</a></p>
76
77<p class="toc_h3"><a href="#3_8_8_activity_switching">3.8.8. Activity Switching</a></p>
78
79<p class="toc_h3"><a href="#3_8_9_input_management">3.8.9. Input Management</a></p>
80
81<p class="toc_h3"><a href="#3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</a></p>
82
83<p class="toc_h3"><a href="#3_8_11_dreams">3.8.11. Dreams</a></p>
84
85<p class="toc_h3"><a href="#3_8_12_location">3.8.12. Location</a></p>
86
87</div>
88
89<div id="toc_right">
90
91
92<p class="toc_h3"><a href="#3_8_13_unicode_and_font">3.8.13. Unicode and Font</a></p>
93
94<p class="toc_h2"><a href="#3_9_device_administration">3.9. Device Administration</a></p>
95
96<p class="toc_h3"><a href="#3_9_1_device_provisioning">3.9.1 Device Provisioning</a></p>
97
98<p class="toc_h4"><a href="#3_9_1_2_device_owner_provisioning">3.9.1.1 Device Owner provisioning</a></p>
99
100<p class="toc_h4"><a href="#3_9_1_2_managed_profile_provisioning">3.9.1.2 Managed profile provisioning</a></p>
101
102<p class="toc_h3"><a href="#3_9_2_managed_profile_support">3.9.2. Managed Profile Support</a></p>
103
104
105<p class="toc_h2"><a href="#3_10_accessibility">3.10. Accessibility</a></p>
106
107<p class="toc_h2"><a href="#3_11_text-to-speech">3.11. Text-to-Speech</a></p>
108
109<p class="toc_h2"><a href="#3_12_tv_input_framework">3.12. TV Input Framework</a></p>
110
111<p class="toc_h3"><a href="#3_12_1_tv_app">3.12.1. TV App</a></p>
112
113<p class="toc_h4"><a href="#3_12_1_1_electronic_program_guide">3.12.1.1. Electronic Program Guide</a></p>
114
115<p class="toc_h4"><a href="#3_12_1_2_navigation">3.12.1.2. Navigation</a></p>
116
117<p class="toc_h4"><a href="#3_12_1_3_tv_input_app_linking">3.12.1.3. TV input app linking</a></p>
118
119<p class="toc_h1"><a href="#4_application_packaging_compatibility">4. Application Packaging Compatibility</a></p>
120
121<p class="toc_h1"><a href="#5_multimedia_compatibility">5. Multimedia Compatibility</a></p>
122
123<p class="toc_h2"><a href="#5_1_media_codecs">5.1. Media Codecs</a></p>
124
125<p class="toc_h3"><a href="#5_1_1_audio_codecs">5.1.1. Audio Codecs</a></p>
126
127<p class="toc_h3"><a href="#5_1_2_image_codecs">5.1.2. Image Codecs</a></p>
128
129<p class="toc_h3"><a href="#5_1_3_video_codecs">5.1.3. Video Codecs</a></p>
130
131<p class="toc_h2"><a href="#5_2_video_encoding">5.2. Video Encoding</a></p>
132
133<p class="toc_h2"><a href="#5_3_video_decoding">5.3. Video Decoding</a></p>
134
135<p class="toc_h2"><a href="#5_4_audio_recording">5.4. Audio Recording</a></p>
136
137<p class="toc_h3"><a href="#5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</a></p>
138
139<p class="toc_h3"><a href="#5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</a></p>
140
141<p class="toc_h3"><a href="#5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</a></p>
142
143<p class="toc_h2"><a href="#5_5_audio_playback">5.5. Audio Playback</a></p>
144
145<p class="toc_h3"><a href="#5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</a></p>
146
147<p class="toc_h3"><a href="#5_5_2_audio_effects">5.5.2. Audio Effects</a></p>
148
149<p class="toc_h3"><a href="#5_5_3_audio_output_volume">5.5.3. Audio Output Volume</a></p>
150
151<p class="toc_h2"><a href="#5_6_audio_latency">5.6. Audio Latency</a></p>
152
153<p class="toc_h2"><a href="#5_7_network_protocols">5.7. Network Protocols</a></p>
154
155<p class="toc_h2"><a href="#5_8_secure_media">5.8. Secure Media</a></p>
156
157<p class="toc_h2"><a href="#5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</a></p>
158
159<p class="toc_h2"><a href="#5_10_pro_audio">5.10. Professional Audio</a></p>
160
161</div>
162
163<div style="clear: both; page-break-after:always; height:1px"></div>
164
165<div id="toc_left">
166
167<p class="toc_h1"><a href="#6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</a></p>
168
169<p class="toc_h2"><a href="#6_1_developer_tools">6.1. Developer Tools</a></p>
170
171<p class="toc_h2"><a href="#6_2_developer_options">6.2. Developer Options</a></p>
172
173<p class="toc_h1"><a href="#7_hardware_compatibility">7. Hardware Compatibility</a></p>
174
175<p class="toc_h2"><a href="#7_1_display_and_graphics">7.1. Display and Graphics</a></p>
176
177<p class="toc_h3"><a href="#7_1_1_screen_configuration">7.1.1. Screen Configuration</a></p>
178
179<p class="toc_h4"><a href="#7_1_1_1_screen_size">7.1.1.1. Screen Size</a></p>
180
181<p class="toc_h4"><a href="#7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</a></p>
182
183<p class="toc_h4"><a href="#7_1_1_3_screen_density">7.1.1.3. Screen Density</a></p>
184
185<p class="toc_h3"><a href="#7_1_2_display_metrics">7.1.2. Display Metrics</a></p>
186
187<p class="toc_h3"><a href="#7_1_3_screen_orientation">7.1.3. Screen Orientation</a></p>
188
189<p class="toc_h3"><a href="#7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</a></p>
190
191<p class="toc_h3"><a href="#7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</a></p>
192
193<p class="toc_h3"><a href="#7_1_6_screen_technology">7.1.6. Screen Technology</a></p>
194
195<p class="toc_h3"><a href="#7_1_7_external_displays">7.1.7. Secondary Displays</a></p>
196
197<p class="toc_h2"><a href="#7_2_input_devices">7.2. Input Devices</a></p>
198
199<p class="toc_h3"><a href="#7_2_1_keyboard">7.2.1. Keyboard</a></p>
200
201<p class="toc_h3"><a href="#7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</a></p>
202
203<p class="toc_h3"><a href="#7_2_3_navigation_keys">7.2.3. Navigation Keys</a></p>
204
205<p class="toc_h3"><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen Input</a></p>
206
207<p class="toc_h3"><a href="#7_2_5_fake_touch_input">7.2.5. Fake Touch Input</a></p>
208
209<p class="toc_h3"><a href="#7_2_6_game_controller_support">7.2.6. Game Controller Support</a></p>
210
211<p class="toc_h4"><a href="#7_2_6_1_button_mapping">7.2.6.1. Button Mappings</a></p>
212
213<p class="toc_h3"><a href="#7_2_7_remote_control">7.2.7. Remote Control</a></p>
214
215<p class="toc_h2"><a href="#7_3_sensors">7.3. Sensors</a></p>
216
217<p class="toc_h3"><a href="#7_3_1_accelerometer">7.3.1. Accelerometer</a></p>
218
219<p class="toc_h3"><a href="#7_3_2_magnetometer">7.3.2. Magnetometer</a></p>
220
221<p class="toc_h3"><a href="#7_3_3_gps">7.3.3. GPS</a></p>
222
223</div>
224
225<div id="toc_right">
226
227<p class="toc_h3"><a href="#7_3_4_gyroscope">7.3.4. Gyroscope</a></p>
228
229<p class="toc_h3"><a href="#7_3_5_barometer">7.3.5. Barometer</a></p>
230
231<p class="toc_h3"><a href="#7_3_6_thermometer">7.3.6. Thermometer</a></p>
232
233<p class="toc_h3"><a href="#7_3_7_photometer">7.3.7. Photometer</a></p>
234
235<p class="toc_h3"><a href="#7_3_8_proximity_sensor">7.3.8. Proximity Sensor</a></p>
236
237<p class="toc_h3"><a href="#7_3_9_hifi_sensors">7.3.9. High Fidelity Sensors</a></p>
238
239<p class="toc_h3"><a href="#7_3_10_fingerprint">7.3.10. Fingerprint Sensor</a></p>
240
241<p class="toc_h2"><a href="#7_4_data_connectivity">7.4. Data Connectivity</a></p>
242
243<p class="toc_h3"><a href="#7_4_1_telephony">7.4.1. Telephony</a></p>
244
245<p class="toc_h3"><a href="#7_4_2_ieee_80211_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
246
247<p class="toc_h4"><a href="#7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</a></p>
248
249<p class="toc_h4"><a href="#7_4_2_2_wi-fi-tunneled-direct-link-setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</a></p>
250
251<p class="toc_h3"><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></p>
252
253<p class="toc_h3"><a href="#7_4_4_near-field_communications">7.4.4. Near-Field Communications</a></p>
254
255<p class="toc_h3"><a href="#7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</a></p>
256
257<p class="toc_h3"><a href="#7_4_6_sync_settings">7.4.6. Sync Settings</a></p>
258
259<p class="toc_h2"><a href="#7_5_cameras">7.5. Cameras</a></p>
260
261<p class="toc_h3"><a href="#7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</a></p>
262
263<p class="toc_h3"><a href="#7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</a></p>
264
265<p class="toc_h3"><a href="#7_5_3_external_camera">7.5.3. External Camera</a></p>
266
267<p class="toc_h3"><a href="#7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</a></p>
268
269<p class="toc_h3"><a href="#7_5_5_camera_orientation">7.5.5. Camera Orientation</a></p>
270
271<p class="toc_h2"><a href="#7_6_memory_and_storage">7.6. Memory and Storage</a></p>
272
273<p class="toc_h3"><a href="#7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</a></p>
274
275<p class="toc_h3"><a href="#7_6_2_application_shared_storage">7.6.2. Application Shared Storage</a></p>
276
277<p class="toc_h3"><a href="#7_6_3_adoptable_storage">7.6.3. Adoptable Storage</a></p>
278
279<p class="toc_h2"><a href="#7_7_usb">7.7. USB</a></p>
280
281<p class="toc_h2"><a href="#7_8_audio">7.8. Audio</a></p>
282
283<p class="toc_h3"><a href="#7_8_1_microphone">7.8.1. Microphone</a></p>
284
285<p class="toc_h3"><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></p>
286
287<p class="toc_h4"><a href="#7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</a></p>
288
289<p class="toc_h3"><a href="#7_8_3_near_ultrasound">7.8.3. Near-Ultrasound</a></p>
290
291<p class="toc_h1"><a href="#8_performance_power">8. Performance and Power</a></p>
292
293<p class="toc_h2"><a href="#8_1_user_experience_consistency">8.1. User Experience Consistency</a></p>
294
295<p class="toc_h2"><a href="#8_2_file_i_o_access_performance">8.2. File I/O Access Performance</a></p>
296
297<p class="toc_h2"><a href="#8_3_power_saving_modes">8.3. Power-Saving Modes</a></p>
298
299<p class="toc_h2"><a href="#8_4_power_consumption_accounting">8.4. Power Consumption Accounting</a></p>
300
301</div>
302
303<div style="clear: both; page-break-after:always; height:1px"></div>
304
305<div id="toc_left">
306
307<p class="toc_h1"><a href="#9_security_model_compatibility">9. Security Model Compatibility</a></p>
308
309<p class="toc_h2"><a href="#9_1_permissions">9.1. Permissions</a></p>
310
311<p class="toc_h2"><a href="#9_2_uid_and_process_isolation">9.2. UID and Process Isolation</a></p>
312
313<p class="toc_h2"><a href="#9_3_filesystem_permissions">9.3. Filesystem Permissions</a></p>
314
315<p class="toc_h2"><a href="#9_4_alternate_execution_environments">9.4. Alternate Execution Environments</a></p>
316
317<p class="toc_h2"><a href="#9_5_multi-user_support">9.5. Multi-User Support</a></p>
318
319<p class="toc_h2"><a href="#9_6_premium_sms_warning">9.6. Premium SMS Warning</a></p>
320
321<p class="toc_h2"><a href="#9_7_kernel_security_features">9.7. Kernel Security Features</a></p>
322
323<p class="toc_h2"><a href="#9_8_privacy">9.8. Privacy</a></p>
324
325<p class="toc_h2"><a href="#9_9_full-disk-encryption">9.9. Full-Disk Encryption</a></p>
326
327<p class="toc_h2"><a href="#9_10_verified_boot">9.10. Verified Boot</a></p>
328
329<p class="toc_h2"><a href="#9_11_keys_and_credentials">9.11. Keys and Credentials</a></p>
330
331<p class="toc_h2"><a href="#9_12_data_deletion">9.12. Data Deletion</a></p>
332
333<p class="toc_h1"><a href="#10_software_compatibility_testing">10. Software Compatibility Testing</a></p>
334
335<p class="toc_h2"><a href="#10_1_compatibility_test_suite">10.1. Compatibility Test Suite</a></p>
336
337<p class="toc_h2"><a href="#10_2_cts_verifier">10.2. CTS Verifier</a></p>
338
339<p class="toc_h1"><a href="#11_updatable_software">11. Updatable Software</a></p>
340
341<p class="toc_h1"><a href="#12_document_changelog">12. Document Changelog</a></p>
342
343<p class="toc_h1"><a href="#13_contact_us">13. Contact Us</a></p>
344
345<p class="toc_h1"><a href="#14_resources">14. Resources</a></p>
346
347</div>
348
349</div>
350
351<div style="clear: both"></div>
352
353<div id="main">
354
355<h1 id="1_introduction">1. Introduction</h1>
356
357
358<p>This document enumerates the requirements that must be met in order for devices
359to be compatible with Android 6.0.</p>
360
361<p>The use of &ldquo;MUST&rdquo;, &ldquo;MUST NOT&rdquo;, &ldquo;REQUIRED&rdquo;, &ldquo;SHALL&rdquo;, &ldquo;SHALL NOT&rdquo;, &ldquo;SHOULD&rdquo;, &ldquo;SHOULD NOT&rdquo;, &ldquo;RECOMMENDED&rdquo;, &ldquo;MAY&rdquo;, and &ldquo;OPTIONAL&rdquo; is per the IETF standard
362defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
363
364<p>As used in this document, a &ldquo;device implementer&rdquo; or &ldquo;implementer&rdquo; is a person
365or organization developing a hardware/software solution running Android 6.0. A
366&ldquo;device implementation&rdquo; or &ldquo;implementation is the hardware/software solution
367so developed.</p>
368
369<p>To be considered compatible with Android 6.0, device implementations MUST meet
370the requirements presented in this Compatibility Definition, including any
371documents incorporated via reference.</p>
372
373<p>Where this definition or the software tests described in <a href="#10_software_compatibility_testing">section 10</a> is silent, ambiguous, or incomplete, it is the responsibility of the device
374implementer to ensure compatibility with existing implementations.</p>
375
376<p>For this reason, the Android Open Source Project [<a href="http://source.android.com/">Resources, 2</a>] is both the reference and preferred implementation of Android. Device
377implementers are STRONGLY RECOMMENDED to base their implementations to the
378greatest extent possible on the &ldquo;upstream&rdquo; source code available from the
379Android Open Source Project. While some components can hypothetically be
380replaced with alternate implementations, it is STRONGLY RECOMMENDED to not follow this practice,
381as passing the software tests will become substantially more difficult. It is
382the implementer&rsquo;s responsibility to ensure full behavioral compatibility with
383the standard Android implementation, including and beyond the Compatibility
384Test Suite. Finally, note that certain component substitutions and
385modifications are explicitly forbidden by this document.</p>
386
387<p>Many of the resources listed in <a href="#14_resources">section 14</a> are derived directly or indirectly from the Android SDK, and will be
388functionally identical to the information in that SDK&rsquo;s documentation. For any
389case where this Compatibility Definition or the Compatibility Test Suite
390disagrees with the SDK documentation, the SDK documentation is considered
391authoritative. Any technical details provided in the references included in <a href="#14_resources">section 14</a> are considered by inclusion to be part of this Compatibility Definition. </p>
392
393<h1 id="2_device_types">2. Device Types</h1>
394
395
396<p>While the Android Open Source Project has been used in the implementation of a
397variety of device types and form factors, many aspects of the architecture and
398compatibility requirements were optimized for handheld devices. Starting from
399Android 5.0, the Android Open Source Project aims to embrace a wider variety of
400device types as described in this section.</p>
401
402<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
403it in the hand, such as mp3 players, phones, and tablets. Android Handheld
404device implementations:</p>
405
406<ul>
407 <li>MUST have a touchscreen embedded in the device.</li>
408 <li>MUST have a power source that provides mobility, such as a battery.</li>
409</ul>
410
411<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
412for consuming digital media, movies, games, apps, and/or live TV for users
413sitting about ten feet away (a &ldquo;lean back&rdquo; or &ldquo;10-foot user interface&rdquo;).
414Android Television devices:</p>
415
416<ul>
417 <li>MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
418or a wireless port for display.</li>
419 <li>MUST declare the features android.software.leanback and
420android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>].</li>
421</ul>
422
423<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
424perhaps on the wrist, and:</p>
425
426<ul>
427 <li>MUST have a screen with the physical diagonal length in the range from 1.1 to
4282.5 inches.</li>
429 <li>MUST declare the feature android.hardware.type.watch.</li>
430 <li>MUST support uiMode = UI_MODE_TYPE_WATCH [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_WATCH">Resources, 4</a>].</li>
431</ul>
432
433<p><strong>Android Automotive implementation</strong> refers to a vehicle head
434unit running Android as an operating system for part or all of the system and/or
435infotainment functionality. Android Automotive implementations:</p>
436
437<ul>
438 <li>MUST declare the feature android.hardware.type.automotive.</li>
439 <li>MUST support
440uiMode = UI_MODE_TYPE_CAR [<a
441href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">Resources,
442 5</a>].</li>
443</ul>
444
445<p>All Android device implementations that do not fit into any of the above device
446types still MUST meet all requirements in this document to be Android 6.0
447compatible, unless the requirement is explicitly described to be only
448applicable to a specific Android device type from above.</p>
449
450<h2 id="2_1_device_configurations">2.1 Device Configurations</h2>
451
452
453<p>This is a summary of major differences in hardware configuration by device
454type. (Empty cells denote a &ldquo;MAY&rdquo;). Not all configurations are covered in this
455table; see relevant hardware sections for more detail.</p>
456<table>
457 <tr>
458 <th>Category</th>
459 <th>Feature</th>
460 <th>Section</th>
461 <th>Handheld</th>
462 <th>Television</th>
463 <th>Watch</th>
464 <th>Automotive</th>
465 <th>Other</th>
466 </tr>
467 <tr>
468 <td rowspan="3">Input</td>
469 <td>D-pad</td>
470 <td><a href="#7_2_2_non-touch-navigation">7.2.2. Non-touch Navigation</a></td>
471 <td></td>
472 <td>MUST</td>
473 <td></td>
474 <td></td>
475 <td></td>
476 </tr>
477 <tr>
478 <td>Touchscreen </td>
479 <td><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen input</a></td>
480 <td>MUST</td>
481 <td></td>
482 <td>MUST</td>
483 <td></td>
484 <td>SHOULD</td>
485 </tr>
486 <tr>
487 <td>Microphone </td>
488 <td><a href="#7_8_1_microphone">7.8.1. Microphone</a></td>
489 <td>MUST</td>
490 <td>SHOULD </td>
491 <td>MUST</td>
492 <td>MUST</td>
493 <td>SHOULD</td>
494 </tr>
495 <tr>
496 <td rowspan="2">Sensors</td>
497 <td>Accelerometer </td>
498 <td><a href="#7_3_1_accelerometer">7.3.1 Accelerometer</a></td>
499 <td>SHOULD</td>
500 <td></td>
501 <td>SHOULD</td>
502 <td></td>
503 <td>SHOULD</td>
504 </tr>
505 <tr>
506 <td>GPS</td>
507 <td><a href="#7_3_3_gps">7.3.3. GPS</a></td>
508 <td>SHOULD</td>
509 <td></td>
510 <td></td>
511 <td>SHOULD</td>
512 <td></td>
513 </tr>
514 <tr>
515 <td rowspan="5">Connectivity</td>
516 <td>Wi-Fi</td>
517 <td><a href="#7_4_2_ieee_802.11">7.4.2. IEEE 802.11</a></td>
518 <td>SHOULD</td>
519 <td> MUST</td>
520 <td></td>
521 <td>SHOULD</td>
522 <td>SHOULD</td>
523 </tr>
524 <tr>
525 <td>Wi-Fi Direct</td>
526 <td><a href="#7_4_2_1_wi-fi-direct">7.4.2.1. Wi-Fi Direct</a></td>
527 <td>SHOULD</td>
528 <td>SHOULD</td>
529 <td></td>
530 <td></td>
531 <td>SHOULD</td>
532 </tr>
533 <tr>
534 <td>Bluetooth</td>
535 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
536 <td>SHOULD</td>
537 <td>MUST</td>
538 <td>MUST</td>
539 <td>MUST</td>
540 <td>SHOULD</td>
541 </tr>
542 <tr>
543 <td>Bluetooth Low Energy</td>
544 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
545 <td>SHOULD</td>
546 <td>MUST</td>
547 <td>SHOULD</td>
548 <td>SHOULD</td>
549 <td>SHOULD</td>
550 </tr>
551 <tr>
552 <td>USB peripheral/host mode</td>
553 <td><a href="#7_7_usb">7.7. USB</a></td>
554 <td>SHOULD</td>
555 <td></td>
556 <td></td>
557 <td>SHOULD</td>
558 <td>SHOULD</td>
559 </tr>
560 <tr>
561 <td>Output</td>
562 <td>Speaker and/or Audio output ports</td>
563 <td><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></td>
564 <td>MUST</td>
565 <td>MUST</td>
566 <td></td>
567 <td>MUST</td>
568 <td>MUST</td>
569 </tr>
570</table>
571
572
573<h1 id="3_software">3. Software</h1>
574
575
576<h2 id="3_1_managed_api_compatibility">3.1. Managed API Compatibility</h2>
577
578
579<p>The managed Dalvik bytecode execution environment is the primary vehicle for
580Android applications. The Android application programming interface (API) is
581the set of Android platform interfaces exposed to applications running in the
582managed runtime environment. Device implementations MUST provide complete
583implementations, including all documented behaviors, of any documented API
584exposed by the Android SDK [<a href="http://developer.android.com/reference/packages.html">Resources, 6</a>] or any API decorated with the &ldquo;@SystemApi&rdquo; marker in the upstream Android
585source code. </p>
586
587<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
588signatures, deviate from the documented behavior, or include no-ops, except
589where specifically allowed by this Compatibility Definition.</p>
590
591<p>This Compatibility Definition permits some types of hardware for which Android
592includes APIs to be omitted by device implementations. In such cases, the APIs
593MUST still be present and behave in a reasonable way. See <a href="#7_hardware_compatibility">section 7</a> for specific requirements for this scenario.</p>
594
595<h2 id="3_2_soft_api_compatibility">3.2. Soft API Compatibility</h2>
596
597
598<p>In addition to the managed APIs from <a href="#3_1_managed_api_compatibility">section 3.1</a>, Android also includes a significant runtime-only &ldquo;soft&rdquo; API, in the form of
599such things as intents, permissions, and similar aspects of Android
600applications that cannot be enforced at application compile time.</p>
601
602<h3 id="3_2_1_permissions">3.2.1. Permissions</h3>
603
604
605<p>Device implementers MUST support and enforce all permission constants as
606documented by the Permission reference page [<a href="http://developer.android.com/reference/android/Manifest.permission.html">Resources, 7</a>]. Note that <a href="#9_security_model_compatibility">section 9</a> lists additional requirements related to the Android security model.</p>
607
608<h3 id="3_2_2_build_parameters">3.2.2. Build Parameters</h3>
609
610
611<p>The Android APIs include a number of constants on the android.os.Build class [<a href="http://developer.android.com/reference/android/os/Build.html">Resources, 8</a>] that are intended to describe the current device. To provide consistent,
612meaningful values across device implementations, the table below includes
613additional restrictions on the formats of these values to which device
614implementations MUST conform.</p>
615<table>
616 <tr>
617 <th>Parameter</th>
618 <th>Details</th>
619 </tr>
620 <tr>
621 <td>VERSION.RELEASE</td>
622 <td>The version of the currently-executing Android system, in human-readable
623format. This field MUST have one of the string values defined in [<a href="http://source.android.com/compatibility/6.0/versions.html">Resources, 9</a>].</td>
624 </tr>
625 <tr>
626 <td>VERSION.SDK</td>
627 <td>The version of the currently-executing Android system, in a format accessible
628to third-party application code. For Android 6.0, this field MUST have the
629integer value 23.</td>
630 </tr>
631 <tr>
632 <td>VERSION.SDK_INT</td>
633 <td>The version of the currently-executing Android system, in a format accessible
634to third-party application code. For Android 6.0, this field MUST have the
635integer value 23.</td>
636 </tr>
637 <tr>
638 <td>VERSION.INCREMENTAL</td>
639 <td>A value chosen by the device implementer designating the specific build of the
640currently-executing Android system, in human-readable format. This value MUST
641NOT be reused for different builds made available to end users. A typical use
642of this field is to indicate which build number or source-control change
643identifier was used to generate the build. There are no requirements on the
644specific format of this field, except that it MUST NOT be null or the empty
645string ("").</td>
646 </tr>
647 <tr>
648 <td>BOARD</td>
649 <td>A value chosen by the device implementer identifying the specific internal
650hardware used by the device, in human-readable format. A possible use of this
651field is to indicate the specific revision of the board powering the device.
652The value of this field MUST be encodable as 7-bit ASCII and match the regular
653expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
654 </tr>
655 <tr>
656 <td>BRAND</td>
657 <td>A value reflecting the brand name associated with the device as known to the
658end users. MUST be in human-readable format and SHOULD represent the
659manufacturer of the device or the company brand under which the device is
660marketed. The value of this field MUST be encodable as 7-bit ASCII and match
661the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
662 </tr>
663 <tr>
664 <td>SUPPORTED_ABIS</td>
665 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
666 </tr>
667 <tr>
668 <td>SUPPORTED_32_BIT_ABIS</td>
669 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
670 </tr>
671 <tr>
672 <td>SUPPORTED_64_BIT_ABIS</td>
673 <td>The name of the second instruction set (CPU type + ABI convention) of native
674code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
675 </tr>
676 <tr>
677 <td>CPU_ABI</td>
678 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
679 </tr>
680 <tr>
681 <td>CPU_ABI2</td>
682 <td>The name of the second instruction set (CPU type + ABI convention) of native
683code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
684 </tr>
685 <tr>
686 <td>DEVICE</td>
687 <td>A value chosen by the device implementer containing the development name or
688code name identifying the configuration of the hardware features and industrial
689design of the device. The value of this field MUST be encodable as 7-bit ASCII
690and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
691 </tr>
692 <tr>
693 <td>FINGERPRINT</td>
694 <td>A string that uniquely identifies this build. It SHOULD be reasonably
695human-readable. It MUST follow this template:
696<p class="small">$(BRAND)/$(PRODUCT)/<br>
697 &nbsp;&nbsp;&nbsp;&nbsp;$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
698<p>For example:</p>
699<p class="small">acme/myproduct/<br>
700 &nbsp;&nbsp;&nbsp;&nbsp;mydevice:6.0/LMYXX/3359:userdebug/test-keys</p>
701<p>The fingerprint MUST NOT include whitespace characters. If other fields
702included in the template above have whitespace characters, they MUST be
703replaced in the build fingerprint with another character, such as the
704underscore ("_") character. The value of this field MUST be encodable as 7-bit
705ASCII.</p></td>
706 </tr>
707 <tr>
708 <td>HARDWARE</td>
709 <td>The name of the hardware (from the kernel command line or /proc). It SHOULD be
710reasonably human-readable. The value of this field MUST be encodable as 7-bit
711ASCII and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;. </td>
712 </tr>
713 <tr>
714 <td>HOST</td>
715 <td>A string that uniquely identifies the host the build was built on, in
716human-readable format. There are no requirements on the specific format of this
717field, except that it MUST NOT be null or the empty string ("").</td>
718 </tr>
719 <tr>
720 <td>ID</td>
721 <td>An identifier chosen by the device implementer to refer to a specific release,
722in human-readable format. This field can be the same as
723android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
724meaningful for end users to distinguish between software builds. The value of
725this field MUST be encodable as 7-bit ASCII and match the regular expression &ldquo;^[a-zA-Z0-9._-]+$&rdquo;.</td>
726 </tr>
727 <tr>
728 <td>MANUFACTURER</td>
729 <td>The trade name of the Original Equipment Manufacturer (OEM) of the product.
730There are no requirements on the specific format of this field, except that it
731MUST NOT be null or the empty string ("").</td>
732 </tr>
733 <tr>
734 <td>MODEL</td>
735 <td>A value chosen by the device implementer containing the name of the device as
736known to the end user. This SHOULD be the same name under which the device is
737marketed and sold to end users. There are no requirements on the specific
738format of this field, except that it MUST NOT be null or the empty string ("").</td>
739 </tr>
740 <tr>
741 <td>PRODUCT</td>
742 <td>A value chosen by the device implementer containing the development name or
743code name of the specific product (SKU) that MUST be unique within the same
744brand. MUST be human-readable, but is not necessarily intended for view by end
745users. The value of this field MUST be encodable as 7-bit ASCII and match the
746regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
747 </tr>
748 <tr>
749 <td>SERIAL</td>
750 <td>A hardware serial number, which MUST be available and unique across
751devices with the same MODEL and MANUFACTURER. The value of this field MUST
752be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
753 </tr>
754 <tr>
755 <td>TAGS</td>
756 <td>A comma-separated list of tags chosen by the device implementer that further
757distinguishes the build. This field MUST have one of the values corresponding
758to the three typical Android platform signing configurations: release-keys,
759dev-keys, test-keys. </td>
760 </tr>
761 <tr>
762 <td>TIME</td>
763 <td>A value representing the timestamp of when the build occurred.</td>
764 </tr>
765 <tr>
766 <td>TYPE</td>
767 <td>A value chosen by the device implementer specifying the runtime configuration
768of the build. This field MUST have one of the values corresponding to the three
769typical Android runtime configurations: user, userdebug, or eng.</td>
770 </tr>
771 <tr>
772 <td>USER</td>
773 <td>A name or user ID of the user (or automated user) that generated the build.
774There are no requirements on the specific format of this field, except that it
775MUST NOT be null or the empty string ("").</td>
776 </tr>
777 <tr>
778 <td>SECURITY_PATCH</td>
779 <td>An value indicating the security patch level of a build. It MUST signify that the
780build includes all security patches issued up through the designated Android Public
781Security Bulletin. It MUST be in the format, [YYYY-MM-DD], matching the Public Security
782Bulletin's broadcast date, for example [2015-10-01].</td>
783 </tr>
784 <tr>
785 <td>BASE_OS</td>
786 <td>An value representing the FINGERPRINT parameter of the build that is otherwise
787 identical to this build except for the patches provided in the Android Public
788 Security Bulletin. It MUST report the correct value and if such a build does not
789 exist, report an emtpy string ("").</td>
790 </tr>
791</table>
792
793
794<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
795
796
797<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
798described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
799implementer MUST provide an Android Activity or Service that specifies a
800matching intent filter that binds to and implements correct behavior for each
801specified intent pattern.</p>
802
803<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
804
805
806<p>Android intents allow application components to request functionality from
807other Android components. The Android upstream project includes a list of
808applications considered core Android applications, which implements several
809intent patterns to perform common actions. The core Android applications are:</p>
810
811<ul>
812 <li>Desk Clock</li>
813 <li>Browser</li>
814 <li>Calendar</li>
815 <li>Contacts</li>
816 <li>Gallery</li>
817 <li>GlobalSearch</li>
818 <li>Launcher</li>
819 <li>Music</li>
820 <li>Settings</li>
821</ul>
822
823<p>Device implementations SHOULD include the core Android applications as
824appropriate but MUST include a component implementing the same intent patterns
825defined by all the &ldquo;public&rdquo; Activity or Service components of these core
826Android applications. Note that Activity or Service components are considered
827&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
828
829<h4 id="3_2_3_2_intent_resolution">3.2.3.2. Intent Resolution</h4>
830
831
832<p>As Android is an extensible platform, device implementations MUST allow each
833intent pattern referenced in <a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>
834to be overridden by third-party applications. The upstream Android open source
835implementation allows this by default; device implementers MUST NOT attach
836special privileges to system applications' use of these intent patterns, or
837prevent third-party applications from binding to and assuming control of these
838patterns. This prohibition specifically includes but is not limited to
839disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
840multiple applications that all handle the same intent pattern.</p>
841
842<p>Device implementations MUST provide a user interface for users to modify the default
843activity for intents.</p>
844
845<p>However, device implementations MAY provide default activities for specific URI
846patterns (eg. http://play.google.com) when the default activity provides a more
847specific attribute for the data URI. For example, an intent filter pattern specifying
848the data URI &ldquo;http://www.android.com&rdquo; is more specific than the browser's
849core intent pattern for &ldquo;http://&rdquo;.</p>
850
851<p>Android also includes a mechanism for third-party apps to declare an authoritative
852default app linking behavior for certain types of web URI intents [<a
853href="https://developer.android.com/training/app-links">Resources, 140</a>]. When such
854authoritative declarations are defined in an app's intent filter patterns, device
855implementations:</p>
856
857<ul>
858<li>MUST attempt to validate any intent filters by performing the validation steps
859defined in the Digital Asset Links specification [<a
860href="https://developers.google.com/digital-asset-links">Resources, 141</a>] as implemented
861by the Package Manager in the upstream Android Open Source Project.</li>
862<li>MUST attempt validation of the intent filters during the installation of the
863application and set all successfully validated UIR intent filters as default app handlers
864for their UIRs.</li>
865<li>MAY set specific URI intent filters as default app handlers for their URIs, if they
866are successfully verified but other candidate URI filters fail verification. If a device
867implementation does this, it MUST provide the user appropriate per-URI pattern overrides
868in the settings menu.</li>
869<li>MUST provide the user with per-app App Links controls in Settings as follows:
870 <ul>
871 <li>The user MUST be able to override holistically the default app links behavior for
872 an app to be: always open, always ask, or never open, which must apply to all candidate
873 URI intent filters equally.</li>
874 <li>The user MUST be able to see a list of the candidate URI intent filters.</li>
875 <li>The device implementation MAY provide the user with the ability to override specific
876 candidate URI intent filters that were successfully verified, on a per-intent filter basis.
877 </li>
878 <li>The device implementation MUST provide users with the ability to view and override
879 specific candidate URI intent filters if the device implementation lets some candidate
880 URI intent filters succeed verification while some others can fail.</li>
881 </ul>
882</li>
883</ul>
884
885<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
886
887
888<p>Device implementations MUST NOT include any Android component that honors any
889new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
890string in the android.* or com.android.* namespace. Device implementers MUST
891NOT include any Android components that honor any new intent or broadcast
892intent patterns using an ACTION, CATEGORY, or other key string in a package
893space belonging to another organization. Device implementers MUST NOT alter or
894extend any of the intent patterns used by the core apps listed in <a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. Device implementations MAY include intent patterns using namespaces clearly
895and obviously associated with their own organization. This prohibition is
896analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
897
898<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
899
900
901<p>Third-party applications rely on the platform to broadcast certain intents to
902notify them of changes in the hardware or software environment.
903Android-compatible devices MUST broadcast the public broadcast intents in
904response to appropriate system events. Broadcast intents are described in the
905SDK documentation.</p>
906
907<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
908
909
910<p>Android includes settings that provide users an easy way to select their
911default applications, for example for Home screen or SMS. Where it makes sense,
912device implementations MUST provide a similar settings menu and be compatible
913with the intent filter pattern and API methods described in the SDK
914documentation as below.</p>
915
916<p>Device implementations:</p>
917
918<ul>
919 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
920settings menu for Home Screen, if the device implementation reports
921android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10</a>]</li>
922 <li>MUST provide a settings menu that will call the
923android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
924change the default SMS application, if the device implementation reports
925android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 11</a>]</li>
926 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
927app settings menu for Tap and Pay, if the device implementation reports
928android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10</a>]</li>
929</ul>
930
931<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
932
933
934<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
935
936
937<p>Managed Dalvik bytecode can call into native code provided in the application
938.apk file as an ELF .so file compiled for the appropriate device hardware
939architecture. As native code is highly dependent on the underlying processor
940technology, Android defines a number of Application Binary Interfaces (ABIs) in
941the Android NDK. Device implementations MUST be compatible with one or more
942defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
943
944<p>If a device implementation includes support for an Android ABI, it:</p>
945
946<ul>
947 <li>MUST include support for code running in the managed environment to call into
948native code, using the standard Java Native Interface (JNI) semantics</li>
949 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
950the ABI) with each required library in the list below</li>
951 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
952 <li>MUST accurately report the native Application Binary Interface (ABI) supported
953by the device, via the android.os.Build.SUPPORTED_ABIS,
954android.os.Build.SUPPORTED_32_BIT_ABIS, and
955android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
956of ABIs ordered from the most to the least preferred one</li>
957 <li>MUST report, via the above parameters, only those ABIs documented and
958described in the latest version of the Android NDK ABI Management documentation
959[<a href="https://developer.android.com/ndk/guides/abis.html">Resources, 12</a>],
960and MUST include support for the Advanced SIMD (a.k.a. NEON)
961[<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">Resources, 13</a>]
962extension
963 </li>
964 <li>SHOULD be built using the source code and header files available in the
965upstream Android Open Source Project</li>
966</ul>
967
968<p>The following native code APIs MUST be available to apps that include native
969code:</p>
970
971<ul>
972 <li>libc (C library)</li>
973 <li>libm (math library)</li>
974 <li>Minimal support for C++</li>
975 <li>JNI interface</li>
976 <li>liblog (Android logging)</li>
977 <li>libz (Zlib compression)</li>
978 <li>libdl (dynamic linker)</li>
979 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
980 <li>libGLESv2.so (OpenGL ES 2.0)</li>
981 <li>libGLESv3.so (OpenGL ES 3.x)</li>
982 <li>libEGL.so (native OpenGL surface management)</li>
983 <li>libjnigraphics.so</li>
984 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
985 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
986 <li>libandroid.so (native Android activity support)</li>
987 <li>libmediandk.so (native media APIs support)</li>
988 <li>Support for OpenGL, as described below</li>
989</ul>
990
991<p>Note that future releases of the Android NDK may introduce support for
992additional ABIs. If a device implementation is not compatible with an existing
993predefined ABI, it MUST NOT report support for any ABIs at all.</p>
994
995<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
996(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
997Android Extension Pack [<a href="http://developer.android.com/guide/topics/graphics/opengl.html#aep">Resources, 14</a>] function symbols as defined in the NDK release android-21. Although all the
998symbols must be present, only the corresponding functions for OpenGL ES
999versions and extensions actually supported by the device must be fully
1000implemented.</p>
1001
1002<p>Device implementations MUST NOT include a native library with the
1003name libvulkan.so.</p>
1004
1005<p>Native code compatibility is challenging. For this reason, device implementers
1006are <strong>STRONGLY RECOMMENDED</strong> to use the implementations of the libraries listed above from the upstream
1007Android Open Source Project. </p>
1008
1009<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
10103.3.2. 32-bit ARM Native Code Compatibility
1011</h3>
1012
1013<p>The ARMv8 architecture deprecates several CPU operations, including some
1014operations used in existing native code. On 64-bit ARM devices, the following
1015deprecated operations MUST remain available to 32-bit native ARM code, either
1016through native CPU support or through software emulation:</p>
1017
1018<ul>
1019<li>SWP and SWPB instructions</li>
1020<li>SETEND instruction</li>
1021<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
1022</ul>
1023
1024<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
1025from 32-bit ARM native code. For compatibility with applications built using this
1026NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
1027by 32-bit ARM applications:</p>
1028
1029<ul>
1030<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
1031supported by the device</li>
1032<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
1033highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
1034</ul>
1035
1036<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
1037applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
1038non-ARM applications.</p>
1039
1040<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
1041
1042
1043<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
1044
1045<div class="note">
1046<p>Android Watch devices MAY, but all other device implementations MUST provide
1047a complete implementation of the android.webkit.Webview API.</p>
1048</div>
1049
1050
1051<p>The platform feature android.software.webview MUST be reported on any device
1052that provides a complete implementation of the android.webkit.WebView API, and
1053MUST NOT be reported on devices without a complete implementation of the API.
1054The Android Open Source implementation uses code from the Chromium Project to
1055implement the android.webkit.WebView [<a href="http://developer.android.com/reference/android/webkit/WebView.html">Resources, 15</a>]. Because it is not feasible to develop a comprehensive test suite for a web
1056rendering system, device implementers MUST use the specific upstream build of
1057Chromium in the WebView implementation. Specifically:</p>
1058
1059<ul>
1060 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
1061build from the upstream Android Open Source Project for Android 6.0. This build
1062includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 16</a>].</li>
1063 <li>The user agent string reported by the WebView MUST be in this format:
1064<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD); wv)
1065AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
1066Safari/537.36</p>
1067 <ul>
1068 <li>The value of the $(VERSION) string MUST be the same as the value for
1069android.os.Build.VERSION.RELEASE.</li>
1070 <li>The value of the $(MODEL) string MUST be the same as the value for
1071android.os.Build.MODEL.</li>
1072 <li>The value of the $(BUILD) string MUST be the same as the value for
1073android.os.Build.ID.</li>
1074 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
1075upstream Android Open Source Project.</li>
1076 <li>Device implementations MAY omit Mobile in the user agent string.</li>
1077 </ul></li></ul>
1078
1079<p>The WebView component SHOULD include support for as many HTML5 features as
1080possible and if it supports the feature SHOULD conform to the HTML5
1081specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 17</a>].</p>
1082
1083<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
1084
1085<div class="note">
1086<p>Android Television, Watch, and Android Automotive implementations MAY omit a
1087browser application, but MUST support the public intent patterns as described in
1088<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
1089of device implementations MUST include a standalone Browser application for
1090general user web browsing.</p>
1091</div>
1092
1093<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1094However, even if an alternate Browser application is used, the
1095android.webkit.WebView component provided to third-party applications MUST be
1096based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1097
1098<p>Implementations MAY ship a custom user agent string in the standalone Browser
1099application.</p>
1100
1101<p>The standalone Browser application (whether based on the upstream WebKit
1102Browser application or a third-party replacement) SHOULD include support for as
1103much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 17</a>] as possible. Minimally, device implementations MUST support each of these
1104APIs associated with HTML5:</p>
1105
1106<ul>
1107 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 18</a>]</li>
1108 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 19</a>]</li>
1109 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 20</a>]</li>
1110</ul>
1111
1112<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1113[<a href="http://www.w3.org/TR/webstorage/">Resources, 21</a>], and SHOULD support the HTML5/W3C IndexedDB API [<a href="http://www.w3.org/TR/IndexedDB/">Resources, 22</a>]. Note that as the web development standards bodies are transitioning to favor
1114IndexedDB over webstorage, IndexedDB is expected to become a required component
1115in a future version of Android.</p>
1116
1117<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1118
1119
1120<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1121consistent with the preferred implementation of the upstream Android Open
1122Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1123
1124<ul>
1125 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1126 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1127type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1128 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1129</ul>
1130
1131<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1132significant portions of the platform for behavioral compatibility, but not all.
1133It is the responsibility of the implementer to ensure behavioral compatibility
1134with the Android Open Source Project. For this reason, device implementers
1135SHOULD use the source code available via the Android Open Source Project where
1136possible, rather than re-implement significant parts of the system.</p>
1137
1138<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1139
1140
1141<p>Android follows the package and class namespace conventions defined by the Java
1142programming language. To ensure compatibility with third-party applications,
1143device implementers MUST NOT make any prohibited modifications (see below) to
1144these package namespaces:</p>
1145
1146<ul>
1147 <li>java.*</li>
1148 <li>javax.*</li>
1149 <li>sun.*</li>
1150 <li>android.*</li>
1151 <li>com.android.*</li>
1152</ul>
1153
1154<p><strong>Prohibited modifications include</strong>:</p>
1155
1156<ul>
1157 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1158platform by changing any method or class signatures, or by removing classes or
1159class fields.</li>
1160 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1161such modifications MUST NOT impact the stated behavior and Java-language
1162signature of any publicly exposed APIs.</li>
1163 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1164or interfaces, or fields or methods to existing classes or interfaces) to the
1165APIs above.</li>
1166</ul>
1167
1168<p>A &ldquo;publicly exposed element&rdquo; is any construct which is not decorated with the&ldquo;@hide&rdquo; marker as used in the upstream Android source code. In other words,
1169device implementers MUST NOT expose new APIs or alter existing APIs in the
1170namespaces noted above. Device implementers MAY make internal-only
1171modifications, but those modifications MUST NOT be advertised or otherwise
1172exposed to developers.</p>
1173
1174<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1175namespace owned by or referring to another organization. For instance, device
1176implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1177Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1178namespaces. Additionally, if a device implementation includes custom APIs
1179outside the standard Android namespace, those APIs MUST be packaged in an
1180Android shared library so that only apps that explicitly use them (via the
1181lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
1182APIs.</p>
1183
1184<p>If a device implementer proposes to improve one of the package namespaces above
1185(such as by adding useful new functionality to an existing API, or adding a new
1186API), the implementer SHOULD visit <a href="http://source.android.com/">source.android.com</a> and begin the process for contributing changes and code, according to the
1187information on that site.</p>
1188
1189<p>Note that the restrictions above correspond to standard conventions for naming
1190APIs in the Java programming language; this section simply aims to reinforce
1191those conventions and make them binding through inclusion in this Compatibility
1192Definition.</p>
1193
1194<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1195
1196
1197<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1198Dalvik bytecode specification and semantics [<a href="https://android.googlesource.com/platform/dalvik/">Resources, 23</a>]. Device implementers SHOULD use ART, the reference upstream implementation of
1199the Dalvik Executable Format, and the reference implementation&rsquo;s package
1200management system.</p>
1201
1202<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1203accordance with the upstream Android platform, and as specified by the
1204following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1205
1206<p>Note that memory values specified below are considered minimum values and
1207device implementations MAY allocate more memory per application.</p>
1208
1209<table>
1210 <tr>
1211 <th>Screen Layout</th>
1212 <th>Screen Density</th>
1213 <th>Minimum Application Memory</th>
1214 </tr>
1215 <tr>
1216 <td rowspan="12">Android Watch</td>
1217 <td>120 dpi (ldpi)</td>
1218 <td rowspan="3">32MB</td>
1219 </tr>
1220 <tr>
1221 <td>160 dpi (mdpi)</td>
1222 </tr>
1223 <tr>
1224 <td>213 dpi (tvdpi)</td>
1225 </tr>
1226 <tr>
1227 <td>240 dpi (hdpi)</td>
1228 <td rowspan="2">36MB</td>
1229 </tr>
1230 <tr>
1231 <td>280 dpi (280dpi)</td>
1232 </tr>
1233 <tr>
1234 <td>320 dpi (xhdpi)</td>
1235 <td rowspan="2">48MB</td>
1236 </tr>
1237 <tr>
1238 <td>360 dpi (360dpi)</td>
1239 </tr>
1240 <tr>
1241 <td>400 dpi (400dpi)</td>
1242 <td>56MB</td>
1243 </tr>
1244 <tr>
1245 <td>420 dpi (420dpi)</td>
1246 <td>64MB</td>
1247 </tr>
1248 <tr>
1249 <td>480 dpi (xxhdpi)</td>
1250 <td>88MB</td>
1251 </tr>
1252 <tr>
1253 <td>560 dpi (560dpi)</td>
1254 <td>112MB</td>
1255 </tr>
1256 <tr>
1257 <td>640 dpi (xxxhdpi)</td>
1258 <td>154MB</td>
1259 </tr>
1260 <tr>
1261 <td rowspan="12">small/normal</td>
1262 <td>120 dpi (ldpi)</td>
1263 <td rowspan="2">32MB</td>
1264 </tr>
1265 <tr>
1266 <td>160 dpi (mdpi)</td>
1267 </tr>
1268 <tr>
1269 <td>213 dpi (tvdpi)</td>
1270 <td rowspan="3">48MB</td>
1271 </tr>
1272 <tr>
1273 <td>240 dpi (hdpi)</td>
1274 </tr>
1275 <tr>
1276 <td>280 dpi (280dpi)</td>
1277 </tr>
1278 <tr>
1279 <td>320 dpi (xhdpi)</td>
1280 <td rowspan="2">80MB</td>
1281 </tr>
1282 <tr>
1283 <td>360 dpi (360dpi)</td>
1284 </tr>
1285 <tr>
1286 <td>400 dpi (400dpi)</td>
1287 <td>96MB</td>
1288 </tr>
1289 <tr>
1290 <td>420 dpi (420dpi)</td>
1291 <td>112MB</td>
1292 </tr>
1293 <tr>
1294 <td>480 dpi (xxhdpi)</td>
1295 <td>128MB</td>
1296 </tr>
1297 <tr>
1298 <td>560 dpi (560dpi)</td>
1299 <td>192MB</td>
1300 </tr>
1301 <tr>
1302 <td>640 dpi (xxxhdpi)</td>
1303 <td>256MB</td>
1304 </tr>
1305 <tr>
1306 <td rowspan="12">large</td>
1307 <td>120 dpi (ldpi)</td>
1308 <td>32MB</td>
1309 </tr>
1310 <tr>
1311 <td>160 dpi (mdpi)</td>
1312 <td>48MB</td>
1313 </tr>
1314 <tr>
1315 <td>213 dpi (tvdpi)</td>
1316 <td rowspan="2">80MB</td>
1317 </tr>
1318 <tr>
1319 <td>240 dpi (hdpi)</td>
1320 </tr>
1321 <tr>
1322 <td>280 dpi (280dpi)</td>
1323 <td>96MB</td>
1324 </tr>
1325 <tr>
1326 <td>320 dpi (xhdpi)</td>
1327 <td>128MB</td>
1328 </tr>
1329 <tr>
1330 <td>360 dpi (360dpi)</td>
1331 <td>160MB</td>
1332 </tr>
1333 <tr>
1334 <td>400 dpi (400dpi)</td>
1335 <td>192MB</td>
1336 </tr>
1337 <tr>
1338 <td>420 dpi (420dpi)</td>
1339 <td>228MB</td>
1340 </tr>
1341 <tr>
1342 <td>480 dpi (xxhdpi)</td>
1343 <td>256MB</td>
1344 </tr>
1345 <tr>
1346 <td>560 dpi (560dpi)</td>
1347 <td>384MB</td>
1348 </tr>
1349 <tr>
1350 <td>640 dpi (xxxhdpi)</td>
1351 <td>512MB</td>
1352 </tr>
1353 <tr>
1354 <td rowspan="12">xlarge</td>
1355 <td>120 dpi (ldpi)</td>
1356 <td>48MB</td>
1357 </tr>
1358 <tr>
1359 <td>160 dpi (mdpi)</td>
1360 <td>80MB</td>
1361 </tr>
1362 <tr>
1363 <td>213 dpi (tvdpi)</td>
1364 <td rowspan="2">96MB</td>
1365 </tr>
1366 <tr>
1367 <td>240 dpi (hdpi)</td>
1368 </tr>
1369 <tr>
1370 <td>280 dpi (280dpi)</td>
1371 <td>144MB</td>
1372 </tr>
1373 <tr>
1374 <td>320 dpi (xhdpi)</td>
1375 <td>192MB</td>
1376 </tr>
1377 <tr>
1378 <td>360 dpi (360dpi)</td>
1379 <td>240MB</td>
1380 </tr>
1381 <tr>
1382 <td>400 dpi (400dpi)</td>
1383 <td>288MB</td>
1384 </tr>
1385 <tr>
1386 <td>420 dpi (420dpi)</td>
1387 <td>336MB</td>
1388 </tr>
1389 <tr>
1390 <td>480 dpi (xxhdpi)</td>
1391 <td>384MB</td>
1392 </tr>
1393 <tr>
1394 <td>560 dpi (560dpi)</td>
1395 <td>576MB</td>
1396 </tr>
1397 <tr>
1398 <td>640 dpi (xxxhdpi)</td>
1399 <td>768MB</td>
1400 </tr>
1401</table>
1402
1403
1404<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1405
1406
1407<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1408
1409
1410<p>Android includes a launcher application (home screen) and support for
1411third-party applications to replace the device launcher (home screen). Device
1412implementations that allow third-party applications to replace the device home
1413screen MUST declare the platform feature android.software.home_screen.</p>
1414
1415<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1416
1417<div class="note">
1418<p>Widgets are optional for all Android device implementations, but SHOULD be
1419supported on Android Handheld devices.</p>
1420</div>
1421
1422
1423<p>Android defines a component type and corresponding API and lifecycle that
1424allows applications to expose an &ldquo;AppWidget&rdquo; to the end user [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 24</a>] a feature that is STRONGLY RECOMMENDED to be supported on Handheld Device
1425implementations. Device implementations that support embedding widgets on the
1426home screen MUST meet the following requirements and declare support for
1427platform feature android.software.app_widgets.</p>
1428
1429<ul>
1430 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1431interface affordances to add, configure, view, and remove AppWidgets directly
1432within the Launcher.</li>
1433 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1434the standard grid size. See the App Widget Design Guidelines in the Android SDK
1435documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 24</a>] for details.</li>
1436 <li>Device implementations that include support for lock screen MAY support
1437application widgets on the lock screen.</li>
1438</ul>
1439
1440<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1441
1442
1443<p>Android includes APIs that allow developers to notify users of notable events [<a href="http://developer.android.com/guide/topics/ui/notifiers/notifications.html">Resources, 25</a>], using hardware and software features of the device.</p>
1444
1445<p>Some APIs allow applications to perform notifications or attract attention
1446using hardware&#8212;specifically sound, vibration, and light. Device implementations
1447MUST support notifications that use hardware features, as described in the SDK
1448documentation, and to the extent possible with the device implementation
1449hardware. For instance, if a device implementation includes a vibrator, it MUST
1450correctly implement the vibration APIs. If a device implementation lacks
1451hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1452is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1453
1454<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1455etc.) provided for in the APIs
1456[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 26</a>],
1457or in the Status/System Bar icon style guide
1458[<a href="http://developer.android.com/design/style/iconography.html">Resources, 27</a>],
1459which in the case of an Android Television device includes the possibility to not display the
1460notifications. Device implementers MAY provide an alternative user experience for
1461notifications than that provided by the reference Android Open Source
1462implementation; however, such alternative notification systems MUST support
1463existing notification resources, as above. </p>
1464
1465<p>Android includes support for various notifications, such as:</p>
1466
1467<ul>
1468 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1469 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1470 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1471</ul>
1472
1473<p>Android device implementations, when such notifications are made visible, MUST properly execute
1474Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1475APIs [<a href="https://developer.android.com/design/patterns/notifications.html">Resources, 28</a>].
1476</p>
1477
1478<p>Android includes Notification Listener Service APIs that allow apps (once
1479explicitly enabled by the user) to receive a copy of all notifications as they
1480are posted or updated. Device implementations MUST correctly and promptly send
1481notifications in their entirety to all such installed and user-enabled listener
1482services, including any and all metadata attached to the Notification object.</p>
1483
1484<h3 id="3_8_4_search">3.8.4. Search</h3>
1485
1486
1487<p>Android includes APIs [<a href="http://developer.android.com/reference/android/app/SearchManager.html">Resources, 29</a>] that allow developers to incorporate search into their applications, and
1488expose their application&rsquo;s data into the global system search. Generally
1489speaking, this functionality consists of a single, system-wide user interface
1490that allows users to enter queries, displays suggestions as users type, and
1491displays results. The Android APIs allow developers to reuse this interface to
1492provide search within their own apps, and allow developers to supply results to
1493the common global search user interface.</p>
1494
1495<p>Android device implementations SHOULD include global search, a single, shared,
1496system-wide search user interface capable of real-time suggestions in response
1497to user input. Device implementations SHOULD implement the APIs that allow
1498developers to reuse this user interface to provide search within their own
1499applications. Device implementations that implement the global search interface
1500MUST implement the APIs that allow third-party applications to add suggestions
1501to the search box when it is run in global search mode. If no third-party
1502applications are installed that make use of this functionality, the default
1503behavior SHOULD be to display web search engine results and suggestions.</p>
1504
1505<p>Android device implementations SHOULD implement an assistant on the device
1506to handle the Assist action [<a
1507href="http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST">Resources,
150830</a>].</p>
1509
1510<p>Android also includes the Assist APIs to allow applications to elect how much
1511information of the current context is shared with the assistant on the device [<a
1512href="https://developer.android.com/reference/android/app/assist/package-summary.html">Resources,
151331</a>]. Device implementations supporting the Assist action MUST indicate clearly to
1514the end user when the the context is shared by displaying a white light around
1515the edges of the screen. To ensure clear visibility to the end user, the indication MUST
1516meet or exceed the duration and brightness of the Android Open Source Project
1517implementation.</p>
1518
1519<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1520
1521
1522<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1523end user, that disappear after a brief period of time [<a href="http://developer.android.com/reference/android/widget/Toast.html">Resources, 32</a>]. Device implementations MUST display Toasts from applications to end users in
1524some high-visibility manner.</p>
1525
1526<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1527
1528
1529<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1530across an entire Activity or application.</p>
1531
1532<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1533application developers to use if they want to match the Holo theme look and
1534feel as defined by the Android SDK [<a href="http://developer.android.com/guide/topics/ui/themes.html">Resources, 33</a>]. Device implementations MUST NOT alter any of the Holo theme attributes
1535exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 34</a>].</p>
1536
1537<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1538application developers to use if they want to match the design theme&rsquo;s look and
1539feel across the wide variety of different Android device types. Device
1540implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1541of the Material theme attributes or their assets exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html#Theme_Material">Resources, 35</a>].</p>
1542
1543<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1544styles for application developers to use if they want to match the look and
1545feel of the device theme as defined by the device implementer. Device
1546implementations MAY modify the Device Default theme attributes exposed to
1547applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 34</a>].</p>
1548
1549<p>Android supports a variant theme with translucent system bars, which allows
1550application developers to fill the area behind the status and navigation bar
1551with their app content. To enable a consistent developer experience in this
1552configuration, it is important the status bar icon style is maintained across
1553different device implementations. Therefore, Android device implementations
1554MUST use white for system status icons (such as signal strength and battery
1555level) and notifications issued by the system, unless the icon is indicating a
1556problematic status or an app requests a light status bar using the
1557SYSTEM_UI_FLAG_LIGHT_STATUS_BAR flag. When an app requests a light status bar,
1558Android device implementations MUST change the color of the system status icons
1559to black [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 34</a>].</p>
1560
1561<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1562
1563
1564<p>Android defines a component type and corresponding API and lifecycle that
1565allows applications to expose one or more &ldquo;Live Wallpapers&rdquo; to the end user [<a href="http://developer.android.com/reference/android/service/wallpaper/WallpaperService.html">Resources, 36</a>]. Live wallpapers are animations, patterns, or similar images with limited
1566input capabilities that display as a wallpaper, behind other applications.</p>
1567
1568<p>Hardware is considered capable of reliably running live wallpapers if it can
1569run all live wallpapers, with no limitations on functionality, at a reasonable
1570frame rate with no adverse effects on other applications. If limitations in the
1571hardware cause wallpapers and/or applications to crash, malfunction, consume
1572excessive CPU or battery power, or run at unacceptably low frame rates, the
1573hardware is considered incapable of running live wallpaper. As an example, some
1574live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1575Live wallpaper will not run reliably on hardware that does not support multiple
1576OpenGL contexts because the live wallpaper use of an OpenGL context may
1577conflict with other applications that also use an OpenGL context.</p>
1578
1579<p>Device implementations capable of running live wallpapers reliably as described
1580above SHOULD implement live wallpapers, and when implemented MUST report the
1581platform feature flag android.software.live_wallpaper.</p>
1582
1583<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1584
1585<div class="note">
1586<p>As the Recent function navigation key is OPTIONAL, the requirements to
1587implement the overview screen is OPTIONAL for Android Television devices and
1588Android Watch devices.</p>
1589</div>
1590
1591
1592<p>The upstream Android source code includes the overview screen [<a href="http://developer.android.com/guide/components/recents.html">Resources, 37</a>], a system-level user interface for task switching and displaying recently
1593accessed activities and tasks using a thumbnail image of the application&rsquo;s
1594graphical state at the moment the user last left the application. Device
1595implementations including the recents function navigation key as detailed in <a href="#7_2_3_navigation_keys">section 7.2.3</a>, MAY alter the interface but MUST meet the following requirements:</p>
1596
1597<ul>
1598 <li>MUST display affiliated recents as a group that moves together.</li>
1599 <li>MUST support at least up to 20 displayed activities.</li>
1600 <li>MUST at least display the title of 4 activities at a time.</li>
1601 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1602 <li>MUST implement the screen pinning behavior [<a href="http://developer.android.com/about/versions/android-5.0.html#ScreenPinning">Resources, 38</a>] and provide the user with a settings menu to toggle the feature.</li>
1603 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1604interacts with screens.</li>
1605</ul>
1606
1607<p>Device implementations are STRONGLY RECOMMENDED to use the upstream Android user
1608interface (or a similar thumbnail-based interface) for the overview screen.</p>
1609
1610<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1611
1612
1613<p>Android includes support for Input Management and support for third-party input
1614method editors [<a href="http://developer.android.com/guide/topics/text/creating-input-method.html">Resources, 39</a>]. Device implementations that allow users to use third-party input methods on
1615the device MUST declare the platform feature android.software.input_methods and
1616support IME APIs as defined in the Android SDK documentation.</p>
1617
1618<p>Device implementations that declare the android.software.input_methods feature
1619MUST provide a user-accessible mechanism to add and configure third-party input
1620methods. Device implementations MUST display the settings interface in response
1621to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1622
1623<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1624
1625
1626<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1627Media Notification Template that allows media applications to integrate with
1628playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 40</a>].
1629Device implementations that support a lock screen, unless an Android Automotive or Watch
1630implementation, MUST display the Lockscreen Notifications including the Media Notification
1631Template.</p>
1632
1633<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1634
1635
1636<p>Android includes support for interactive screensavers called Dreams [<a href="http://developer.android.com/reference/android/service/dreams/DreamService.html">Resources, 41</a>]. Dreams allows users to interact with applications when a device connected to
1637a power source is idle or docked in a desk dock. Android Watch devices MAY
1638implement Dreams, but other types of device implementations SHOULD include
1639support for Dreams and provide a settings option for users to configure Dreams
1640in response to the android.settings.DREAM_SETTINGS intent.</p>
1641
1642<h3 id="3_8_12_location">3.8.12. Location</h3>
1643
1644
1645<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1646location coordinates, location modes MUST be displayed in the Location menu
1647within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 42</a>].</p>
1648
1649<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1650
1651
1652<p>Android includes support for color emoji characters. When Android device
1653implementations include an IME, devices SHOULD provide an input method to the
1654user for the Emoji characters defined in Unicode 6.1 [<a href="http://www.unicode.org/versions/Unicode6.1.0/">Resources, 43</a>]. All devices MUST be capable of rendering these emoji characters in color glyph.</p>
1655
1656<p>Android includes support for Roboto 2 font with different
1657weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1658sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1659the languages available on the device and full Unicode 7.0 coverage of Latin,
1660Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1661all glyphs in the currency symbols block of Unicode 7.0.</p>
1662
1663<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1664
1665<p>Android includes features that allow security-aware applications to perform
1666device administration functions at the system level, such as enforcing password
1667policies or performing remote wipe, through the Android Device Administration
1668API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 44</a>].
1669Device implementations MUST provide an implementation of the DevicePolicyManager class
1670[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 45</a>].
1671Device implementations that include support for PIN (numeric) or PASSWORD
1672(alphanumeric) based lock screens MUST support the full range of device
1673administration policies defined in the Android SDK documentation
1674[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 44</a>]
1675and report the platform feature android.software.device_admin.</p>
1676
1677<h3 id="3_9_1_device_provisioning">3.9.1 Device Provisioning</h3>
1678<h4 id="3_9_1_1_device_owner_provisioning">3.9.1.1 Device owner provisioning</h4>
1679<p>If a device implementation declares the android.software.device_admin feature,
1680the out of box setup flow MUST make it possible to enroll a Device Policy
1681Controller (DPC) application as the Device Owner app
1682[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">
1683Resources, 46</a>]. Device implementations MAY have a preinstalled application
1684performing device administration functions but this application MUST NOT be set
1685as the Device Owner app without explicit consent or action from the user or the
1686administrator of the device.</p>
1687
1688<p>The device owner provisioning process (the flow initiated by
1689android.app.action.PROVISION_MANAGED_DEVICE
1690[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_DEVICE">
1691Resources, 47</a>]) user experience MUST align with the AOSP implementation</p>
1692
1693<p>If the device implementation reports android.hardware.nfc, it MUST have NFC
1694enabled, even during the out-of-box setup flow, in order to allow for NFC
1695provisioning of Device owners
1696[<a href="https://source.android.com/devices/tech/admin/provision.html#device_owner_provisioning_via_nfc">Resources, 48</a>].
1697</p>
1698
1699<h4 id="3_9_1_2_managed_profile_provisioning">3.9.1.2 Managed profile provisioning</h4>
1700<p>If a device implementation declares the android.software.managed_users,
1701it MUST be possible to enroll a Device Policy Controller (DPC) application
1702as the owner of a new Managed Profile
1703[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isProfileOwnerApp(java.lang.String)">
1704Resources, 49</a>]</p>
1705
1706<p>The managed profile provisioning process (the flow initiated by
1707android.app.action.PROVISION_MANAGED_PROFILE
1708[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE">
1709Resources, 50</a>]) user experience MUST align with the AOSP implementation
1710</p>
1711
1712
1713<h2 id="3_9_2_managed_profile_support">3.9.2 Managed Profile Support</h2>
1714
1715<p>Managed profile capable devices are those devices that:</p>
1716<ul>
1717 <li>Declare android.software.device_admin (see <a href="#3_9_device_administration">section 3.9 Device Administration)</a></li>
1718 <li>Are not low RAM devices (see <a href="#7_6_1_minimum_memory_and_storage">section 7.6.1</a></li>
1719 <li>Allocate internal (non-removable) storage as shared storage (see
1720 <a href="#7_6_2_application_shared_storage">section 7.6.2</a>)</li>
1721</ul>
1722<p>Managed profile capable devices MUST:</p>
1723<ul>
1724 <li>Declare the platform feature flag android.software.managed_users.</li>
1725 <li>Support managed profiles via the android.app.admin.DevicePolicyManager APIs</li>
1726 <li>Allow one and only one managed profile to be created [<a
1727href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE">Resources,
172850</a>]</li>
1729 <li>Use an icon badge (similar to the AOSP upstream work badge) to represent
1730the managed applications and widgets and other badged UI elements like Recents
1731&amp; Notifications</li>
1732 <li>Display a notification icon (similar to the AOSP upstream work badge) to
1733indicate when user is within a managed profile application</li>
1734 <li>Display a toast indicating that the user is in the managed profile if and when the
1735device wakes up (ACTION_USER_PRESENT) and the foreground application is within
1736the managed profile</li>
1737 <li>Where a managed profile exists, show a visual affordance in the Intent
1738'Chooser' to allow the user to forward the intent from the managed profile to
1739the primary user or vice versa, if enabled by the Device Policy Controller</li>
1740 <li>Where a managed profile exists, expose the following user affordances for both
1741the primary user and the managed profile:
1742 <ul>
1743 <li>Separate accounting for battery, location, mobile data and storage usage
1744 for the primary user and managed profile.</li>
1745 <li>Independent management of VPN Applications installed within the primary
1746 user or managed profile.</li>
1747 <li>Independent management of applications installed within the primary user
1748 user or managed profile.</li>
1749 <li>Independent management of accounts within the primary user or managed
1750 profile.</li>
1751 </ul>
1752 </li>
1753 <li>Ensure the default dialer can look up caller information from the managed
1754profile (if one exists) alongside those from the primary profile, if the Device
1755Policy Controller permits it.</li>
1756 <li>MUST ensure that it satisfies all the security requirements applicable for a device
1757 with multiple users enabled (see <a href="#9_5_multi-user_support">section 9.5</a>),
1758 even though the managed profile is not counted as another user in addition to the
1759 primary user.</li>
1760</ul>
1761
1762<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1763
1764
1765<p>Android provides an accessibility layer that helps users with disabilities to
1766navigate their devices more easily. In addition, Android provides platform APIs
1767that enable accessibility service implementations to receive callbacks for user
1768and system events and generate alternate feedback mechanisms, such as
1769text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 51</a>].</p>
1770
1771<p>Device implementations include the following requirements:</p>
1772
1773<ul>
1774<li>Android Automotive implementations SHOULD provide an implementation of the
1775Android accessibility framework consistent with the default Android
1776implementation.</li>
1777<li>Device implementations (Android Automotive excluded) MUST provide an
1778implementation of the Android accessibility framework consistent with the
1779default Android implementation.</li>
1780<li>Device implementations (Android Automotive excluded) MUST support
1781third-party accessibility service implementations through the
1782android.accessibilityservice APIs
1783[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 52</a>]</li>
1784<li>Device implementations (Android Automotive excluded) MUST generate
1785AccessibilityEvents and deliver these events to all registered
1786AccessibilityService implementations in a manner consistent with the default
1787Android implementation</li>
1788<li> Device implementations (Android Automotive and Android Watch devices with
1789no audio output excluded), MUST provide a user-accessible mechanism to enable
1790and disable accessibility services, and MUST display this interface in response
1791to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1792</ul>
1793
1794<p>Additionally, device implementations SHOULD provide an implementation of an
1795accessibility service on the device, and SHOULD provide a mechanism for users
1796to enable the accessibility service during device setup. An open source
1797implementation of an accessibility service is available from the Eyes Free
1798project [<a href="http://code.google.com/p/eyes-free/">Resources, 53</a>].</p>
1799
1800<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1801
1802
1803<p>Android includes APIs that allow applications to make use of text-to-speech
1804(TTS) services and allows service providers to provide implementations of TTS
1805services [<a href="http://developer.android.com/reference/android/speech/tts/package-summary.html">Resources, 54</a>]. Device implementations reporting the feature android.hardware.audio.output
1806MUST meet these requirements related to the Android TTS framework. </p>
1807
1808<p>Android Automotive implementations:</p>
1809<ul>
1810<li>MUST support the Android TTS framework APIs.</li>
1811<li>MAY support installation of third-party TTS engines. If supported, partners
1812MUST provide a user-accessible interface that allows the user to select a TTS
1813engine for use at system level.</li>
1814</ul>
1815
1816<p>All other device implementations:</p>
1817
1818<ul>
1819 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1820supporting the languages available on the device. Note that the upstream
1821Android open source software includes a full-featured TTS engine
1822implementation.
1823 <li> MUST support installation of third-party TTS engines
1824 <li> MUST provide a user-accessible interface that allows users to select a TTS
1825engine for use at the system level
1826</ul>
1827
1828<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1829
1830
1831<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1832content to Android Television devices. TIF provides a standard API to create
1833input modules that control Android Television devices. Android Television
1834device implementations MUST support TV Input Framework
1835[<a href="http://source.android.com/devices/tv/index.html">Resources, 55</a>].</p>
1836
1837<p>Device implementations that support TIF MUST declare the platform feature
1838android.software.live_tv.</p>
1839
1840<h3 id="3_12_1_tv_app">3.12.1. TV App</h3>
1841
1842<p>Any device implementation that declares support for Live TV MUST have an
1843installed TV application (TV App). The Android Open Source Project provides an implementation of the TV
1844App.</p>
1845
1846<p>The TV App MUST provide facilities to install and use TV Channels
1847[<a href="http://developer.android.com/reference/android/media/tv/TvContract.Channels.html">Resources, 56</a>]
1848 and meet the following requirements:</p>
1849
1850<ul>
1851 <li>Device implementations MUST allow third-party TIF-based inputs (third-party inputs)
1852[<a href="https://source.android.com/devices/tv/index.html#third-party_input_example">Resources, 57</a>]
1853 to be installed and managed.
1854 <li>Device implementations MAY provide visual separation between pre-installed
1855 TIF-based inputs (installed inputs)
1856[<a href="https://source.android.com/devices/tv/index.html#tv_inputs">Resources, 58</a>]
1857 and third-party inputs.
1858 <li>The device implementations MUST NOT display the third-party inputs more than a
1859single navigation action away from the TV App (i.e. expanding a list of
1860third-party inputs from the TV App).
1861</ul>
1862
1863<h4 id="3_12_1_1_electronic_program_guide">3.12.1.1. Electronic Program Guide</h4>
1864
1865<p>Android Television device implementations MUST show an informational and
1866interactive overlay, which MUST include an electronic program guide (EPG)
1867generated from the values in the TvContract.Programs fields
1868[<a href="https://developer.android.com/reference/android/media/tv/TvContract.Programs.html">Resources, 59</a>].
1869 The EPG MUST meet the following requirements:</p>
1870
1871<ul>
1872 <li>The EPG MUST display information from all installed inputs and third-party
1873inputs.
1874 <li>The EPG MAY provide visual separation between the installed inputs and
1875third-party inputs.
1876 <li>The EPG is STRONGLY RECOMMENDED to display installed inputs and third-party
1877inputs with equal prominence. The EPG MUST NOT display the third-party inputs
1878more than a single navigation action away from the installed inputs on the EPG.
1879 <li>On channel change, device implementations MUST display EPG data for the
1880currently playing program.
1881</ul>
1882
1883<h4 id="3_12_1_2_navigation">3.12.1.2. Navigation</h4>
1884
1885<p>Android Television device input devices (i.e. remote control, remote control
1886application, or game controller) MUST allow navigation to all actionable
1887sections of the screen via the D-pad. D-pad up and down MUST be used to change
1888live TV channels when there is no actionable section on the screen.</p>
1889
1890<p>The TV App SHOULD pass key events to HDMI inputs through CEC.</p>
1891
1892<h4 id="3_12_1_3_tv_input_app_linking">3.12.1.3. TV input app linking</h4>
1893
1894<p>Android Television device implementations MUST support TV input app linking,
1895which allows all inputs to provide activity links from the current activity to
1896another activity (i.e. a link from live programming to related content)
1897[<a href="http://developer.android.com/reference/android/media/tv/TvContract.Channels.html#COLUMN_APP_LINK_INTENT_URI">Resources, 60</a>].
1898 The TV App MUST show TV input app linking when it is provided.</p>
1899
1900<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1901
1902
1903<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1904by the &ldquo;aapt&rdquo; tool included in the official Android SDK [<a href="http://developer.android.com/tools/help/index.html">Resources, 61</a>].</p>
1905
1906<p>Devices implementations MUST NOT extend either the .apk [<a href="http://developer.android.com/guide/components/fundamentals.html">Resources, 62</a>], Android Manifest [<a href="http://developer.android.com/guide/topics/manifest/manifest-intro.html">Resources, 49</a>], Dalvik bytecode [<a href="https://android.googlesource.com/platform/dalvik/">Resources, 23</a>], or RenderScript bytecode formats in such a way that would prevent those
1907files from installing and running correctly on other compatible devices.</p>
1908
1909<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1910
1911
1912<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1913
1914
1915<p>Device implementations MUST support the core media formats specified in the
1916Android SDK documentation [<a href="http://developer.android.com/guide/appendix/media-formats.html">Resources, 64</a>]
1917except where explicitly permitted in this document. Specifically, device
1918implementations MUST support the media formats, encoders, decoders, file types,
1919and container formats defined in the tables below and reported via MediaCodecList
1920[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources, 65</a>].
1921Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1922[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
192366</a>] and MUST be able to decode all formats it can encode.
1924
1925All of these codecs are
1926provided as software implementations in the preferred Android implementation
1927from the Android Open Source Project.</p>
1928
1929<p>Please note that neither Google nor the Open Handset Alliance make any
1930representation that these codecs are free from third-party patents. Those
1931intending to use this source code in hardware or software products are advised
1932that implementations of this code, including in open source software or
1933shareware, may require patent licenses from the relevant patent holders.</p>
1934
1935<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1936
1937<table>
1938 <tr>
1939 <th>Format/Codec</th>
1940 <th>Encoder</th>
1941 <th>Decoder</th>
1942 <th>Details</th>
1943 <th>Supported File Types/Container Formats</th>
1944 </tr>
1945 <tr>
1946 <td>MPEG-4 AAC Profile<br />
1947
1948(AAC LC)</td>
1949 <td>REQUIRED<sup>1</sup></td>
1950 <td>REQUIRED</td>
1951 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 8 to
195248 kHz.</td>
1953 <td>
1954 <ul>
1955 <li class="table_list">3GPP (.3gp)</li>
1956 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1957 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1958supported)</li>
1959 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1960 </tr>
1961 <tr>
1962 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1963 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1964 <td>REQUIRED</td>
1965 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 16
1966to 48 kHz.</td>
1967 <td></td>
1968 </tr>
1969 <tr>
1970 <td>MPEG-4 HE AACv2<br />
1971
1972Profile (enhanced AAC+)</td>
1973 <td> </td>
1974 <td>REQUIRED</td>
1975 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 16
1976to 48 kHz.</td>
1977 <td></td>
1978 </tr>
1979 <tr>
1980 <td>AAC ELD (enhanced low delay AAC)</td>
1981 <td>REQUIRED<sup>1</sup> <br />
1982
1983(Android 4.1+)</td>
1984 <td>REQUIRED<br />
1985
1986(Android 4.1+)</td>
1987 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1988 <td></td>
1989 </tr>
1990 <tr>
1991 <td>AMR-NB</td>
1992 <td>REQUIRED<sup>3</sup></td>
1993 <td>REQUIRED<sup>3</sup></td>
1994 <td>4.75 to 12.2 kbps sampled @ 8 kHz</td>
1995 <td>3GPP (.3gp)</td>
1996 </tr>
1997 <tr>
1998 <td>AMR-WB</td>
1999 <td>REQUIRED<sup>3</sup></td>
2000 <td>REQUIRED<sup>3</sup></td>
2001 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16 kHz</td>
2002 <td></td>
2003 </tr>
2004 <tr>
2005 <td>FLAC</td>
2006 <td></td>
2007 <td>REQUIRED <br>(Android 3.1+)</td>
2008 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
2009RECOMMENDED on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
2010does not include a low-pass filter). 16-bit RECOMMENDED; no dither applied for
201124-bit.</td>
2012 <td>FLAC (.flac) only</td>
2013 </tr>
2014 <tr>
2015 <td>MP3</td>
2016 <td></td>
2017 <td>REQUIRED</td>
2018 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
2019 <td>MP3 (.mp3)</td>
2020 </tr>
2021 <tr>
2022 <td>MIDI</td>
2023 <td></td>
2024 <td>REQUIRED</td>
2025 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
2026ringtone formats RTTTL/RTX, OTA, and iMelody</td>
2027 <td><ul>
2028 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
2029 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
2030 <li class="table_list">OTA (.ota)</li>
2031 <li class="table_list">iMelody (.imy)</li></ul></td>
2032 </tr>
2033 <tr>
2034 <td>Vorbis</td>
2035 <td></td>
2036 <td>REQUIRED</td>
2037 <td></td>
2038 <td><ul>
2039 <li class="table_list">Ogg (.ogg)</li>
2040 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
2041 </tr>
2042 <tr>
2043 <td>PCM/WAVE</td>
2044 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
2045 <td>REQUIRED</td>
2046 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
2047sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
2048frequencies.</td>
2049 <td>WAVE (.wav)</td>
2050 </tr>
2051 <tr>
2052 <td>Opus</td>
2053 <td></td>
2054 <td>REQUIRED<br> (Android 5.0+)</td>
2055 <td></td>
2056 <td>Matroska (.mkv)</td>
2057 </tr>
2058</table>
2059
2060
2061<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
2062but optional for Android Watch device implementations.</p>
2063
2064<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
20652 channels is optional.</p>
2066
2067<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
2068
2069<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
2070including Android Watch device implementations.</p>
2071
2072<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
2073
2074<table>
2075 <tr>
2076 <th>Format/Codec</th>
2077 <th>Encoder</th>
2078 <th>Decoder</th>
2079 <th>Details</th>
2080 <th>Supported File Types/Container Formats</th>
2081 </tr>
2082 <tr>
2083 <td>JPEG</td>
2084 <td>REQUIRED</td>
2085 <td>REQUIRED</td>
2086 <td>Base+progressive</td>
2087 <td>JPEG (.jpg)</td>
2088 </tr>
2089 <tr>
2090 <td>GIF</td>
2091 <td></td>
2092 <td>REQUIRED</td>
2093 <td></td>
2094 <td>GIF (.gif)</td>
2095 </tr>
2096 <tr>
2097 <td>PNG</td>
2098 <td>REQUIRED</td>
2099 <td>REQUIRED</td>
2100 <td></td>
2101 <td>PNG (.png)</td>
2102 </tr>
2103 <tr>
2104 <td>BMP</td>
2105 <td></td>
2106 <td>REQUIRED</td>
2107 <td></td>
2108 <td>BMP (.bmp)</td>
2109 </tr>
2110 <tr>
2111 <td>WebP</td>
2112 <td>REQUIRED</td>
2113 <td>REQUIRED</td>
2114 <td></td>
2115 <td>WebP (.webp)</td>
2116 </tr>
2117</table>
2118
2119
2120<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
2121
2122<table>
2123 <tr>
2124 <th>Format/Codec</th>
2125 <th>Encoder</th>
2126 <th>Decoder</th>
2127 <th>Details</th>
2128 <th>Supported File Types/<br>Container Formats</th>
2129 </tr>
2130 <tr>
2131 <td>H.263</td>
2132 <td>REQUIRED<sup>1</sup></td>
2133 <td>REQUIRED<sup>2</sup></td>
2134 <td></td>
2135 <td><ul>
2136 <li class="table_list">3GPP (.3gp)</li>
2137 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
2138 </tr>
2139 <tr>
2140 <td>H.264 AVC</td>
2141 <td>REQUIRED<sup>2</sup></td>
2142 <td>REQUIRED<sup>2</sup></td>
2143 <td>See <a href="#5_2_video_encoding">section 5.2 </a>and <a href="#5_3_video_decoding">5.3</a> for details</td>
2144 <td><ul>
2145 <li class="table_list">3GPP (.3gp)</li>
2146 <li class="table_list">MPEG-4 (.mp4)</li>
2147 <li class="table_list">MPEG-2 TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
2148 </tr>
2149 <tr>
2150 <td>H.265 HEVC</td>
2151 <td></td>
2152 <td>REQUIRED<sup>5</sup></td>
2153 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
2154 <td>MPEG-4 (.mp4)</td>
2155 </tr>
2156<tr>
2157 <td>MPEG-2</td>
2158 <td></td>
2159 <td>STRONGLY RECOMMENDED<sup>6</sup></td>
2160 <td>Main Profile</td>
2161 <td>MPEG2-TS</td>
2162</tr>
2163 <tr>
2164 <td>MPEG-4 SP</td>
2165 <td></td>
2166 <td>REQUIRED<sup>2</sup></td>
2167 <td></td>
2168 <td>3GPP (.3gp)</td>
2169 </tr>
2170 <tr>
2171 <td>VP8<sup>3</sup></td>
2172 <td>REQUIRED<sup>2</sup><br />
2173
2174(Android 4.3+)</td>
2175 <td>REQUIRED<sup>2</sup><br />
2176
2177(Android 2.3.3+)</td>
2178 <td>See <a href="#5_2_video_encoding">section 5.2</a> and <a href="#5_3_video_decoding">5.3</a> for details</td>
2179 <td><ul>
2180 <li class="table_list">WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 67</a></li>
2181 <li class="table_list">Matroska (.mkv, Android 4.0+)<sup>4</sup></li></ul></td>
2182 </tr>
2183 <tr>
2184 <td>VP9</td>
2185 <td></td>
2186 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
2187 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
2188 <td><ul>
2189 <li class="table_list">WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 67</a>]</li>
2190 <li class="table_list">Matroska (.mkv, Android 4.0+)<sup>4</sup></li></ul></td>
2191 </tr>
2192</table>
2193
2194
2195<p class="table_footnote">1 Required for device implementations that include camera hardware and define
2196android.hardware.camera or android.hardware.camera.front.</p>
2197
2198<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
2199
2200<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
2201device implementations SHOULD use a hardware VP8 codec that meets the
2202requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 68</a>].</p>
2203
2204<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
2205
2206<p class="table_footnote">5 STRONGLY RECOMMENDED for Android Automotive, optional for Android Watch, and required for all other device types.</p>
2207
2208<p class="table_footnote">6 Applies only to Android Television device implementations.</p>
2209
2210<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
2211
2212<div class="note">
2213<p>Video codecs are optional for Android Watch device implementations.</p>
2214</div>
2215
2216<p>Android device implementations with H.263 encoders, MUST support Baseline Profile Level 45.</p>
2217
2218<p>Android device implementations with H.264 codec support, MUST support Baseline
2219Profile Level 3 and the following SD (Standard Definition) video encoding
2220profiles and SHOULD support Main Profile Level 4 and the following HD (High
2221Definition) video encoding profiles. Android Television devices are STRONGLY RECOMMENDED
2222to encode HD 1080p video at 30 fps.</p>
2223<table>
2224 <tr>
2225 <th></th>
2226 <th>SD (Low quality)</th>
2227 <th>SD (High quality)</th>
2228 <th>HD 720p<sup>1</sup></th>
2229 <th>HD 1080p<sup>1</sup></th>
2230 </tr>
2231 <tr>
2232 <th>Video resolution</th>
2233 <td>320 x 240 px</td>
2234 <td>720 x 480 px</td>
2235 <td>1280 x 720 px</td>
2236 <td>1920 x 1080 px</td>
2237 </tr>
2238 <tr>
2239 <th>Video frame rate</th>
2240 <td>20 fps</td>
2241 <td>30 fps</td>
2242 <td>30 fps</td>
2243 <td>30 fps</td>
2244 </tr>
2245 <tr>
2246 <th>Video bitrate</th>
2247 <td>384 Kbps</td>
2248 <td>2 Mbps</td>
2249 <td>4 Mbps</td>
2250 <td>10 Mbps</td>
2251 </tr>
2252</table>
2253
2254
2255<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
2256devices.</p>
2257
2258<p>Android device implementations with VP8 codec support MUST support the SD video
2259encoding profiles and SHOULD support the following HD (High Definition) video
2260encoding profiles.</p>
2261<table>
2262 <tr>
2263 <th></th>
2264 <th>SD (Low quality)</th>
2265 <th>SD (High quality)</th>
2266 <th>HD 720p<sup>1</sup></th>
2267 <th>HD 1080p<sup>1</sup></th>
2268 </tr>
2269 <tr>
2270 <th>Video resolution</th>
2271 <td>320 x 180 px</td>
2272 <td>640 x 360 px</td>
2273 <td>1280 x 720 px</td>
2274 <td>1920 x 1080 px</td>
2275 </tr>
2276 <tr>
2277 <th>Video frame rate</th>
2278 <td>30 fps</td>
2279 <td>30 fps</td>
2280 <td>30 fps</td>
2281 <td>30 fps</td>
2282 </tr>
2283 <tr>
2284 <th>Video bitrate</th>
2285 <td>800 Kbps </td>
2286 <td>2 Mbps</td>
2287 <td>4 Mbps</td>
2288 <td>10 Mbps</td>
2289 </tr>
2290</table>
2291
2292<p class="table_footnote">1 When supported by hardware.</p>
2293
2294<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
2295
2296<div class="note">
2297<p>Video codecs are optional for Android Watch device implementations.</p>
2298</div>
2299
2300<p>Device implementations MUST support dynamic video resolution and frame rate
2301switching through the standard Android APIs within the same stream for all VP8,
2302VP9, H.264, and H.265 codecs in real time and up to the maximum resolution
2303supported on the device.</p>
2304
2305<p>Android device implementations with H.263 decoders, MUST support Baseline
2306Profile Level 30.</p>
2307
2308<p>Android device implementations with MPEG-4 decoders, MUST support Simple
2309Profile Level 3.</p>
2310
2311<p>Android device implementations with H.264 decoders, MUST support Main Profile
2312Level 3.1 and the following SD video decoding profiles and SHOULD support the
2313HD decoding profiles. Android Television devices MUST support High Profile
2314Level 4.2 and the HD 1080p decoding profile.</p>
2315<table>
2316 <tr>
2317 <th></th>
2318 <th>SD (Low quality)</th>
2319 <th>SD (High quality)</th>
2320 <th>HD 720p<sup>1</sup></th>
2321 <th>HD 1080p<sup>1</sup></th>
2322 </tr>
2323 <tr>
2324 <th>Video resolution</th>
2325 <td>320 x 240 px</td>
2326 <td>720 x 480 px</td>
2327 <td>1280 x 720 px</td>
2328 <td>1920 x 1080 px</td>
2329 </tr>
2330 <tr>
2331 <th>Video frame rate</th>
2332 <td>30 fps</td>
2333 <td>30 fps</td>
2334 <td>60 fps</td>
2335 <td>30 fps / 60 fps<sup>2</sup></td>
2336 </tr>
2337 <tr>
2338 <th>Video bitrate</th>
2339 <td>800 Kbps </td>
2340 <td>2 Mbps</td>
2341 <td>8 Mbps</td>
2342 <td>20 Mbps</td>
2343 </tr>
2344</table>
2345
2346
2347<p class="table_footnote">1 REQUIRED for when the height as reported by the
2348Display.getSupportedModes() method is not smaller than the video resolution.</p>
2349
2350<p class="table_footnote">2 REQUIRED for Android Television device implementations.</p>
2351
2352<p>Android device implementations when supporting VP8 codec as described in <a href="#5_1_3_video_codecs">section 5.1.3</a>, MUST support the following SD decoding profiles and SHOULD support the HD
2353decoding profiles. Android Television devices MUST support the HD 1080p
2354decoding profile. </p>
2355<table>
2356 <tr>
2357 <th></th>
2358 <th>SD (Low quality)</th>
2359 <th>SD (High quality)</th>
2360 <th>HD 720p<sup>1</sup></th>
2361 <th>HD 1080p<sup>1</sup></th>
2362 </tr>
2363 <tr>
2364 <th>Video resolution</th>
2365 <td>320 x 180 px</td>
2366 <td>640 x 360 px</td>
2367 <td>1280 x 720 px</td>
2368 <td>1920 x 1080 px</td>
2369 </tr>
2370 <tr>
2371 <th>Video frame rate</th>
2372 <td>30 fps</td>
2373 <td>30 fps</td>
2374 <td>30 fps / 60 fps<sup>2</sup></td>
2375 <td>30 / 60 fps<sup>2</sup></td>
2376 </tr>
2377 <tr>
2378 <th>Video bitrate</th>
2379 <td>800 Kbps </td>
2380 <td>2 Mbps</td>
2381 <td>8 Mbps</td>
2382 <td>20 Mbps</td>
2383 </tr>
2384</table>
2385
2386<p class="table_footnote">1 REQUIRED for when the height as reported by the
2387Display.getSupportedModes() method is not smaller than the video resolution.</p>
2388
2389<p class="table_footnote">2 REQUIRED for Android Television device implementations.</p>
2390
2391<p>Android device implementations, when supporting VP9 codec as described in <a href="#5_1_3_video_codecs">section 5.1.3</a>, MUST support the following SD video decoding profiles and SHOULD support the
2392HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2393support the HD 1080p decoding profile and SHOULD support the UHD decoding
2394profile. When the UHD video decoding profile is supported, it MUST support 8-bit
2395color depth and SHOULD support VP9 Profile 2 (10-bit).</p>
2396<table>
2397 <tr>
2398 <th></th>
2399 <th>SD (Low quality)</th>
2400 <th>SD (High quality)</th>
2401 <th>HD 720p<sup>1</sup></th>
2402 <th>HD 1080p<sup>2</sup></th>
2403 <th>UHD<sup>2</sup></th>
2404 </tr>
2405 <tr>
2406 <th>Video resolution</th>
2407 <td>320 x 180 px</td>
2408 <td>640 x 360 px</td>
2409 <td>1280 x 720 px</td>
2410 <td>1920 x 1080 px</td>
2411 <td>3840 x 2160 px</td>
2412 </tr>
2413 <tr>
2414 <th>Video frame rate</th>
2415 <td>30 fps</td>
2416 <td>30 fps</td>
2417 <td>30 fps</td>
2418 <td>60 fps</td>
2419 <td>60 fps</td>
2420 </tr>
2421 <tr>
2422 <th>Video bitrate</th>
2423 <td>600 Kbps</td>
2424 <td>1.6 Mbps</td>
2425 <td>4 Mbps</td>
2426 <td>10 Mbps</td>
2427 <td>20 Mbps</td>
2428 </tr>
2429</table>
2430
2431
2432<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2433devices only when supported by hardware.</p>
2434
2435<p class="table_footnote">2 STRONGLY RECOMMENDED for existing Android Television device implementations when
2436supported by hardware.</p>
2437
2438<p>Android device implementations, when supporting H.265 codec as described in <a href="#5_1_3_video_codecs">section 5.1.3</a>, MUST support the Main Profile Level 3 Main tier and the following SD video
2439decoding profiles and SHOULD support the HD decoding profiles. Android
2440Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
24411080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2442the UHD decoding profile.</p>
2443<table>
2444 <tr>
2445 <th></th>
2446 <th>SD (Low quality)</th>
2447 <th>SD (High quality)</th>
2448 <th>HD 720p<sup>1</sup></th>
2449 <th>HD 1080p<sup>1</sup></th>
2450 <th>UHD<sup>2</sup></th>
2451 </tr>
2452 <tr>
2453 <th>Video resolution</th>
2454 <td>352 x 288 px</td>
2455 <td>640 x 360 px</td>
2456 <td>1280 x 720 px</td>
2457 <td>1920 x 1080 px</td>
2458 <td>3840 x 2160 px</td>
2459 </tr>
2460 <tr>
2461 <th>Video frame rate</th>
2462 <td>30 fps</td>
2463 <td>30 fps</td>
2464 <td>30 fps</td>
2465 <td>60 fps<sup>2</sup></td>
2466 <td>60 fps</td>
2467 </tr>
2468 <tr>
2469 <th>Video bitrate</th>
2470 <td>600 Kbps </td>
2471 <td>1.6 Mbps</td>
2472 <td>4 Mbps</td>
2473 <td>10 Mbps</td>
2474 <td>20 Mbps</td>
2475 </tr>
2476</table>
2477
2478
2479<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2480devices only when supported by hardware.</p>
2481
2482<p class="table_footnote">2 STRONGLY RECOMMENDED
2483for existing Android Television device implementations when supported by hardware.</p>
2484
2485<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2486
2487
2488<p>While some of the requirements outlined in this section are stated as SHOULD
2489since Android 4.3, the Compatibility Definition for a future version is planned
2490to change these to MUST. Existing and new Android devices are <strong>STRONGLY RECOMMENDED</strong>
2491to meet these requirements, or they will not be able to attain Android compatibility when upgraded
2492to the future version.</p>
2493
2494<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2495
2496
2497<p>Device implementations that declare android.hardware.microphone MUST allow
2498capture of raw audio content with the following characteristics:</p>
2499
2500<ul>
2501 <li><strong>Format</strong>: Linear PCM, 16-bit
2502 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2503 <li><strong>Channels</strong>: Mono
2504</ul>
2505
2506<p>The capture for the above sample rates MUST be done without up-sampling, and
2507any down-sampling MUST include an appropriate anti-aliasing filter.</p>
2508
2509<p>Device implementations that declare android.hardware.microphone SHOULD allow
2510capture of raw audio content with the following characteristics:</p>
2511
2512<ul>
2513 <li><strong>Format</strong>: Linear PCM, 16-bit
2514 <li><strong>Sampling rates</strong>: 22050, 48000
2515 <li><strong>Channels</strong>: Stereo
2516</ul>
2517
2518<p>If capture for the above sample rates is supported,
2519then the capture MUST be done without up-sampling at any ratio higher than 16000:22050
2520or 44100:48000.
2521Any up-sampling or down-sampling MUST include an appropriate anti-aliasing filter.</p>
2522
2523<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2524
2525
2526<p>In addition to the above recording specifications, when an application has
2527started recording an audio stream using the
2528android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2529
2530<ul>
2531 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2532characteristics: specifically, &plusmn;3 dB, from 100 Hz to 4000 Hz.
2533 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2534source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2535 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2536dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2537 <li>Total harmonic distortion SHOULD be less than 1% for 1 kHz at 90 dB SPL input
2538level at the microphone.
2539 <li>Noise reduction processing, if present, MUST be disabled.
2540 <li>Automatic gain control, if present, MUST be disabled
2541</ul>
2542
2543<p>If the platform supports noise suppression technologies tuned for speech
2544recognition, the effect MUST be controllable from the
2545android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2546noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2547of the noise suppression technology.</p>
2548
2549<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2550
2551
2552<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2553audio source. Devices that declare android.hardware.audio.output MUST properly
2554implement the REMOTE_SUBMIX audio source so that when an application uses the
2555android.media.AudioRecord API to record from this audio source, it can capture
2556a mix of all audio streams except for the following:</p>
2557
2558<ul>
2559 <li>STREAM_RING
2560 <li>STREAM_ALARM
2561 <li>STREAM_NOTIFICATION
2562</ul>
2563
2564<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2565
2566
2567<p>Device implementations that declare android.hardware.audio.output MUST conform
2568to the requirements in this section.</p>
2569
2570<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2571
2572
2573<p>The device MUST allow playback of raw audio content with the following
2574characteristics:</p>
2575
2576<ul>
2577 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2578 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2579 <li><strong>Channels</strong>: Mono, Stereo</li>
2580</ul>
2581
2582<p>The device SHOULD allow playback of raw audio content with the following
2583characteristics:</p>
2584
2585<ul>
2586 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2587</ul>
2588
2589<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2590
2591
2592<p>Android provides an API for audio effects for device implementations [<a href="http://developer.android.com/reference/android/media/audiofx/AudioEffect.html">Resources, 69</a>]. Device implementations that declare the feature
2593android.hardware.audio.output:</p>
2594
2595<ul>
2596 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2597implementations controllable through the AudioEffect subclasses Equalizer,
2598LoudnessEnhancer.</li>
2599 <li>MUST support the visualizer API implementation, controllable through the
2600Visualizer class.</li>
2601 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2602EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2603controllable through the AudioEffect sub-classes BassBoost,
2604EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2605</ul>
2606
2607<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2608
2609
2610<p>Android Television device implementations MUST include support for system
2611Master Volume and digital audio output volume attenuation on supported outputs,
2612except for compressed audio passthrough output (where no audio decoding is done
2613on the device).</p>
2614
2615<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2616
2617
2618<p>Audio latency is the time delay as an audio signal passes through a system.
2619Many classes of applications rely on short latencies, to achieve real-time
2620sound effects.</p>
2621
2622<p>For the purposes of this section, use the following definitions:</p>
2623
2624<ul>
2625 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2626when the corresponding sound can be heard by an external listener or observed
2627by a transducer.</li>
2628 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2629idle and powered down prior to the request.</li>
2630 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2631 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2632when an application reads the corresponding frame of PCM-coded data.</li>
2633 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2634audio input system has been idle and powered down prior to the request.</li>
2635 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2636 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2637 <li><strong>cold input jitter</strong>. The variance among separate measurements of cold input latency values.</li>
2638 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2639 one buffer period.
2640 The buffer period term allows processing time for the app and for the app to
2641 mitigate phase difference between input and output streams.
2642 </li>
2643 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2644NDK_root/docs/opensles/index.html.</li>
2645</ul>
2646
2647<p>Device implementations that declare android.hardware.audio.output are STRONGLY RECOMMENDED to meet
2648or exceed these audio output requirements:</p>
2649
2650<ul>
2651 <li>cold output latency of 100 milliseconds or less</li>
2652 <li>continuous output latency of 45 milliseconds or less</li>
2653 <li>minimize the cold output jitter</li>
2654</ul>
2655
2656<p>If a device implementation meets the requirements of this section after any
2657initial calibration when using the OpenSL ES PCM buffer queue API, for
2658continuous output latency and cold output latency over at least one supported
2659audio output device, it is STRONGLY RECOMMENDED to report support for low-latency audio, by reporting
2660the feature android.hardware.audio.low_latency via the
2661android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>]. Conversely, if the device implementation does not meet these requirements it
2662MUST NOT report support for low-latency audio.</p>
2663
2664<p>Device implementations that include android.hardware.microphone are STRONGLY RECOMMENDED to meet
2665these input audio requirements:</p>
2666
2667<ul>
2668 <li>cold input latency of 100 milliseconds or less</li>
2669 <li>continuous input latency of 30 milliseconds or less</li>
2670 <li>continuous round-trip latency of 50 milliseconds or less</li>
2671 <li>minimize the cold input jitter</li>
2672</ul>
2673
2674<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2675
2676
2677<p>Devices MUST support the media network protocols for audio and video playback
2678as specified in the Android SDK documentation [<a href="http://developer.android.com/guide/appendix/media-formats.html">Resources, 64</a>]. Specifically, devices MUST support the following media network protocols:</p>
2679
2680<ul>
2681 <li>RTSP (RTP, SDP)</li>
2682 <li>HTTP(S) progressive streaming</li>
2683 <li>HTTP(S) Live Streaming draft protocol, Version 3 [<a href="http://tools.ietf.org/html/draft-pantos-http-live-streaming-03">Resources, 71</a>]</li>
2684</ul>
2685
2686<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2687
2688
2689<p>Device implementations that support secure video output and are capable of
2690supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2691implementations that declare support for Display.FLAG_SECURE, if they support a
2692wireless display protocol, MUST secure the link with a cryptographically strong
2693mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2694if they support a wired external display, the device implementations MUST
2695support HDCP 1.2 or higher. Android Television device implementations MUST
2696support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2697lower resolutions. The upstream Android open source implementation includes
2698support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2699requirement.</p>
2700
2701<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2702
2703<p>
2704If a device implementation supports the inter-app MIDI software transport
2705(virtual MIDI devices), and it supports MIDI over
2706<em>all</em> of the following MIDI-capable hardware transports
2707for which it provides generic non-MIDI connectivity, it is STRONGLY RECOMMENDED to report
2708support for feature android.software.midi via the
2709android.content.pm.PackageManager class
2710[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>].
2711</p>
2712
2713<p>The MIDI-capable hardware transports are:</p>
2714<ul>
2715 <li>USB host mode (section 7.7 USB)</li>
2716 <li>USB peripheral mode (section 7.7 USB)</li>
2717</ul>
2718
2719<p>
2720Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2721MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2722it MUST NOT report support for feature android.software.midi.
2723</p>
2724
2725<p>
2726MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2727is in trial use status. A device implementation that reports
2728feature android.software.midi, and which provides generic non-MIDI connectivity
2729over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2730</p>
2731
2732<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2733
2734<p>
2735If a device implementation meets <em>all</em> of the following requirements,
2736it is STRONGLY RECOMMENDED to report support for feature android.hardware.audio.pro via the
2737android.content.pm.PackageManager class
2738[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>].
2739</p>
2740
2741<ul>
2742
2743<li>
2744The device implementation MUST report support for feature android.hardware.audio.low_latency.
2745</li>
2746
2747<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2748MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2749supported path.
2750</li>
2751
2752<li>
2753If the device includes a 4 conductor 3.5mm audio jack,
2754the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2755and SHOULD be 10 milliseconds or less over at the audio jack path.
2756</li>
2757
2758<li>
2759The device implementation MUST include a USB port(s) supporting USB host mode and
2760USB peripheral mode.
2761</li>
2762
2763<li>
2764The USB host mode MUST implement the USB audio class.
2765</li>
2766
2767<li>
2768If the device includes an HDMI port, the device implementation
2769MUST support output in stereo and eight channels
2770at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2771</li>
2772
2773<li>
2774The device implementation MUST report support for feature android.software.midi.
2775</li>
2776
2777<li>
2778If the device includes a 4 conductor 3.5mm audio jack,
2779the device implementation is STRONGLY RECOMMENDED to comply with section
2780<a href="https://source.android.com/accessories/headset/specification.html#mobile_device_jack_specifications">Mobile device (jack) specifications</a>
2781of the
2782<a href="https://source.android.com/accessories/headset/specification.html">Wired Audio Headset Specification (v1.1)</a>.
2783</li>
2784
2785</ul>
2786
2787<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2788
2789<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2790
2791<p>Device implementations MUST support the Android Developer Tools provided in the
2792Android SDK. Android compatible devices MUST be compatible with:</p>
2793
2794<ul>
2795 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 72</a>]</li>
2796</ul>
2797
2798<p>Device implementations MUST support all adb functions as documented in the
2799Android SDK including dumpsys [<a href="https://source.android.com/devices/input/diagnostics.html">Resources, 73</a>]. The device-side adb daemon MUST be inactive by default and there MUST be a
2800user-accessible mechanism to turn on the Android Debug Bridge. If a device
2801implementation omits USB peripheral mode, it MUST implement the Android Debug
2802Bridge via local-area network (such as Ethernet or 802.11). </p>
2803
2804<p>Android includes support for secure adb. Secure adb enables adb on known
2805authenticated hosts. Device implementations MUST support secure adb.</p>
2806
2807<ul>
2808 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 74</a>]</li>
2809</ul>
2810
2811<p>Device implementations MUST support all ddms features as documented in the
2812Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2813but MUST be supported whenever the user has activated the Android Debug Bridge,
2814as above.</p>
2815
2816<ul>
2817 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 75</a>]</li>
2818</ul>
2819
2820<p>Device implementations MUST include the Monkey framework, and make it available
2821for applications to use.</p>
2822
2823<ul>
2824 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 76</a>]</li>
2825</ul>
2826
2827<p>Device implementations MUST support systrace tool as documented in the Android
2828SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2829mechanism to turn on Systrace.</p>
2830
2831<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2832using the standard Android SDK tools, without additional support; however
2833Microsoft Windows systems typically require a driver for new Android devices.
2834(For instance, new vendor IDs and sometimes new device IDs require custom USB
2835drivers for Windows systems.) If a device implementation is unrecognized by the
2836adb tool as provided in the standard Android SDK, device implementers MUST
2837provide Windows drivers allowing developers to connect to the device using the
2838adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2839Windows 7, Windows 8 and Windows 10 in both 32-bit and 64-bit versions.
2840</p>
2841
2842<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2843
2844
2845<p>Android includes support for developers to configure application
2846development-related settings. Device implementations MUST honor the
2847android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2848development-related settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_APPLICATION_DEVELOPMENT_SETTINGS">Resources, 77</a>]. The upstream Android implementation hides the Developer Options menu by
2849default and enables users to launch Developer Options after pressing seven (7)
2850times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2851Developer Options. Specifically, device implementations MUST hide Developer
2852Options by default and MUST provide a mechanism to enable Developer Options
2853that is consistent with the upstream Android implementation.</p>
2854
2855<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2856
2857
2858<p>If a device includes a particular hardware component that has a corresponding
2859API for third-party developers, the device implementation MUST implement that
2860API as described in the Android SDK documentation. If an API in the SDK
2861interacts with a hardware component that is stated to be optional and the
2862device implementation does not possess that component:</p>
2863
2864<ul>
2865 <li>Complete class definitions (as documented by the SDK) for the component APIs
2866MUST still be presented.
2867 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2868 <li>API methods MUST return null values where permitted by the SDK documentation.
2869 <li>API methods MUST return no-op implementations of classes where null values are
2870not permitted by the SDK documentation.
2871 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2872</ul>
2873
2874<p>A typical example of a scenario where these requirements apply is the telephony
2875API: even on non-phone devices, these APIs must be implemented as reasonable
2876no-ops.</p>
2877
2878<p>Device implementations MUST consistently report accurate hardware configuration
2879information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2880methods on the android.content.pm.PackageManager class for the same build
2881fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>]</p>
2882
2883<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2884
2885
2886<p>Android includes facilities that automatically adjust application assets and UI
2887layouts appropriately for the device, to ensure that third-party applications
2888run well on a variety of hardware configurations [<a href="http://developer.android.com/guide/practices/screens_support.html">Resources, 78</a>]. Devices MUST properly implement these APIs and behaviors, as detailed in
2889this section.</p>
2890
2891<p>The units referenced by the requirements in this section are defined as
2892follows:</p>
2893
2894<ul>
2895 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2896of the display.</li>
2897 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
28981&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2899within the range.</li>
2900 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2901 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2902 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2903 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2904dps * (density/160).</li>
2905</ul>
2906
2907<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2908
2909
2910<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2911
2912<div class="note">
2913<p>Android Watch devices (detailed in <a href="#2_device_types">section 2</a>) MAY have smaller screen sizes as described in this section.</p>
2914</div>
2915
2916<p>The Android UI framework supports a variety of different screen sizes, and
2917allows applications to query the device screen size (aka &ldquo;screen layout") via
2918android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2919Device implementations MUST report the correct screen size as defined in the
2920Android SDK documentation [<a href="http://developer.android.com/guide/practices/screens_support.html">Resources, 78</a>] and determined by the upstream Android platform. Specifically, device
2921implementations MUST report the correct screen size according to the following
2922logical density-independent pixel (dp) screen dimensions.</p>
2923
2924<ul>
2925 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2926is an Android Watch device.</li>
2927 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2928dp x 320 dp.</li>
2929 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2930dp x 480 dp.</li>
2931 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2932dp x 720 dp.</li>
2933</ul>
2934
2935<p>In addition, </p>
2936
2937<ul>
2938 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2939range from 1.1 to 2.5 inches.</li>
2940 <li>Other types of Android device implementations, with a physically integrated
2941screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2942</ul>
2943
2944<p>Devices MUST NOT change their reported screen size at any time.</p>
2945
2946<p>Applications optionally indicate which screen sizes they support via the
2947&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
2948implementations MUST correctly honor applications' stated support for small,
2949normal, large, and xlarge screens, as described in the Android SDK
2950documentation.</p>
2951
2952<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2953
2954<div class="note">
2955<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2956</div>
2957
2958
2959<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
296016:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2961such a device implementation will use a UI_MODE_TYPE_WATCH as the
2962android.content.res.Configuration.uiMode.</p>
2963
2964<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2965
2966
2967<p>The Android UI framework defines a set of standard logical densities to help
2968application developers target application resources. Device implementations
2969MUST report only one of the following logical Android framework densities
2970through the android.util.DisplayMetrics APIs, and MUST execute applications at
2971this standard density and MUST NOT change the value at at any time for the
2972default display.</p>
2973
2974<ul>
2975 <li>120 dpi (ldpi)</li>
2976 <li>160 dpi (mdpi)</li>
2977 <li>213 dpi (tvdpi)</li>
2978 <li>240 dpi (hdpi)</li>
2979 <li>280 dpi (280dpi)</li>
2980 <li>320 dpi (xhdpi)</li>
2981 <li>360 dpi (360dpi)</li>
2982 <li>400 dpi (400dpi)</li>
2983 <li>420 dpi (420dpi)</li>
2984 <li>480 dpi (xxhdpi)</li>
2985 <li>560 dpi (560dpi)</li>
2986 <li>640 dpi (xxxhdpi)</li>
2987</ul>
2988
2989<p>Device implementations SHOULD define the standard Android framework density
2990that is numerically closest to the physical density of the screen, unless that
2991logical density pushes the reported screen size below the minimum supported. If
2992the standard Android framework density that is numerically closest to the
2993physical density results in a screen size that is smaller than the smallest
2994supported compatible screen size (320 dp width), device implementations SHOULD
2995report the next lowest standard Android framework density.</p>
2996
2997<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2998
2999
3000<p>Device implementations MUST report correct values for all display metrics
3001defined in android.util.DisplayMetrics [<a href="http://developer.android.com/reference/android/util/DisplayMetrics.html">Resources, 79</a>] and MUST report the same values regardless of whether the embedded or
3002external screen is used as the default display.</p>
3003
3004<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
3005
3006
3007<p>Devices MUST report which screen orientations they support
3008(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
3009MUST report at least one supported orientation. For example, a device with a
3010fixed orientation landscape screen, such as a television or laptop, SHOULD only
3011report android.hardware.screen.landscape.</p>
3012
3013<p>Devices that report both screen orientations MUST support dynamic orientation
3014by applications to either portrait or landscape screen orientation. That is,
3015the device must respect the application&rsquo;s request for a specific screen
3016orientation. Device implementations MAY select either portrait or landscape
3017orientation as the default.</p>
3018
3019<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
3020whenever queried via the android.content.res.Configuration.orientation,
3021android.view.Display.getOrientation(), or other APIs.</p>
3022
3023<p>Devices MUST NOT change the reported screen size or density when changing
3024orientation.</p>
3025
3026<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
3027
3028
3029<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
3030detailed in the Android SDK documentations. Device implementations SHOULD
3031support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
3032implementations MUST also support Android RenderScript, as detailed in the
3033Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 80</a>].</p>
3034
3035<p>Device implementations MUST also correctly identify themselves as supporting
3036OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
3037
3038<ul>
3039 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
3040for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
3041 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
3042libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
3043ES 2.0.</li>
3044 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
3045support the corresponding managed APIs and include support for native C/C++
3046APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
3047libGLESv2.so MUST export the corresponding function symbols in addition to the
3048OpenGL ES 2.0 function symbols.</li>
3049</ul>
3050
3051<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
3052interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 81</a>] and native support for advanced graphics functionality such as tessellation
3053and the ASTC texture compression format. Android device implementations MAY
3054support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
3055support through the android.hardware.opengles.aep feature flag.</p>
3056
3057<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
3058However, device implementations MUST report via the OpenGL ES managed and
3059native APIs all extension strings that they do support, and conversely MUST NOT
3060report extension strings that they do not support.</p>
3061
3062<p>Note that Android includes support for applications to optionally specify that
3063they require specific OpenGL texture compression formats. These formats are
3064typically vendor-specific. Device implementations are not required by Android
3065to implement any specific texture compression format. However, they SHOULD
3066accurately report any texture compression formats that they do support, via the
3067getString() method in the OpenGL API.</p>
3068
3069<p>Android includes a mechanism for applications to declare that they want to
3070enable hardware acceleration for 2D graphics at the Application, Activity,
3071Window, or View level through the use of a manifest tag
3072android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 82</a>].</p>
3073
3074<p>Device implementations MUST enable hardware acceleration by default, and MUST
3075disable hardware acceleration if the developer so requests by setting
3076android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
3077through the Android View APIs.</p>
3078
3079<p>In addition, device implementations MUST exhibit behavior consistent with the
3080Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 82</a>].</p>
3081
3082<p>Android includes a TextureView object that lets developers directly integrate
3083hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
3084Device implementations MUST support the TextureView API, and MUST exhibit
3085consistent behavior with the upstream Android implementation.</p>
3086
3087<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
3088that indicates whether the EGLConfig supports rendering to an ANativeWindow
3089that records images to a video. Device implementations MUST support
3090EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 83</a>].</p>
3091
3092<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
3093
3094
3095<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
3096'normal' screen size equivalent (320dp width) mode for the benefit of legacy
3097applications not developed for old versions of Android that pre-date
3098screen-size independence.</p>
3099
3100<ul>
3101<li>Android Automotive does not support legacy compatibility mode.</li>
3102<li>All other device implementations MUST include support for legacy application
3103compatibility mode as implemented by the upstream Android open source code. That
3104is, device implementations MUST NOT alter the triggers or thresholds at which
3105compatibility mode is activated, and MUST NOT alter the behavior of the
3106compatibility mode itself.</li>
3107</ul>
3108
3109<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
3110
3111
3112<p>The Android platform includes APIs that allow applications to render rich
3113graphics to the display. Devices MUST support all of these APIs as defined by
3114the Android SDK unless specifically allowed in this document. </p>
3115
3116<ul>
3117 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
3118SHOULD support displays capable of 24-bit color graphics.</li>
3119 <li>Devices MUST support displays capable of rendering animations.</li>
3120 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
3121and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
312215% tolerance.</li>
3123</ul>
3124
3125<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
3126
3127
3128<p>Android includes support for secondary display to enable media sharing
3129capabilities and developer APIs for accessing external displays. If a device
3130supports an external display either via a wired, wireless, or an embedded
3131additional display connection then the device implementation MUST implement the
3132display manager API as described in the Android SDK documentation [<a href="http://developer.android.com/reference/android/hardware/display/DisplayManager.html">Resources, 84</a>].</p>
3133
3134<h2 id="7_2_input_devices">7.2. Input Devices</h2>
3135
3136<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
3137for non-touch navigation.</p>
3138
3139<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
3140
3141<div class="note">
3142<p>Android Watch and Android Automotive implementations MAY implement a soft
3143keyboard. All other device implementations MUST implement a soft keyboard and:</p>
3144</div>
3145
3146
3147<p>Device implementations:</p>
3148
3149<ul>
3150 <li>MUST include support for the Input Management Framework (which allows
3151third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
3152detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
3153 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
3154hard keyboard is present) except for Android Watch devices where the screen
3155size makes it less reasonable to have a soft keyboard.</li>
3156 <li>MAY include additional soft keyboard implementations.</li>
3157 <li>MAY include a hardware keyboard.</li>
3158 <li>MUST NOT include a hardware keyboard that does not match one of the formats
3159specified in android.content.res.Configuration.keyboard [<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 85</a>] (QWERTY or 12-key).</li>
3160</ul>
3161
3162<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
3163
3164<div class="note">
3165<p>Android Television devices MUST support D-pad.</p>
3166</div>
3167
3168<p>Device implementations:</p>
3169
3170<ul>
3171 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
3172device implementation is not an Android Television device.</li>
3173 <li>MUST report the correct value for android.content.res.Configuration.navigation
3174[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 85</a>].</li>
3175 <li>MUST provide a reasonable alternative user interface mechanism for the
3176selection and editing of text, compatible with Input Management Engines. The
3177upstream Android open source implementation includes a selection mechanism
3178suitable for use with devices that lack non-touch navigation inputs.</li>
3179</ul>
3180
3181<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
3182
3183<div class="note">
3184<p>The availability and visibility requirement of the Home, Recents, and Back
3185functions differ between device types as described in this section.</p>
3186</div>
3187
3188<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
3189KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
3190navigation paradigm and therefore:</p>
3191
3192<ul>
3193 <li>Android Handheld device implementations MUST provide the Home, Recents, and
3194Back functions.</li>
3195 <li>Android Television device implementations MUST provide the Home and Back
3196functions.</li>
3197 <li>Android Watch device implementations MUST have the Home function available to
3198the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
3199 <li>Android Automotive implementations MUST provide the Home function and MAY
3200provide Back and Recent functions.</li>
3201 <li>All other types of device implementations MUST provide the Home and Back
3202functions.</li>
3203</ul>
3204
3205<p>These functions MAY be implemented via dedicated physical buttons (such as
3206mechanical or capacitive touch buttons), or MAY be implemented using dedicated
3207software keys on a distinct portion of the screen, gestures, touch panel, etc.
3208Android supports both implementations. All of these functions MUST be
3209accessible with a single action (e.g. tap, double-click or gesture) when
3210visible.</p>
3211
3212<p>Recents function, if provided, MUST have a visible button or icon unless hidden
3213together with other navigation functions in full-screen mode. This does not
3214apply to devices upgrading from earlier Android versions that have physical
3215buttons for navigation and no recents key.</p>
3216
3217<p> The Home and Back functions, if provided, MUST each have a visible button or
3218icon unless hidden together with other navigation functions in full-screen mode
3219or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
3220
3221<p>The Menu function is deprecated in favor of action bar since Android 4.0.
3222Therefore the new device implementations shipping with Android 6.0 and later MUST NOT
3223implement a dedicated physical button for the Menu function. Older device
3224implementations SHOULD NOT implement a dedicated physical button for the Menu
3225function, but if the physical Menu button is implemented and the device is
3226running applications with targetSdkVersion > 10, the device implementation:</p>
3227
3228<ul>
3229 <li>MUST display the action overflow button on the action bar when it is visible
3230and the resulting action overflow menu popup is not empty. For a device
3231implementation launched before Android 4.4 but upgrading to Android 6.0, this
3232is RECOMMENDED.</li>
3233 <li>MUST NOT modify the position of the action overflow popup displayed by
3234selecting the overflow button in the action bar.</li>
3235 <li>MAY render the action overflow popup at a modified position on the screen when
3236it is displayed by selecting the physical menu button.</li>
3237</ul>
3238
3239<p>For backwards compatibility, device implementations MUST make the Menu function
3240available to applications when targetSdkVersion is less than 10, either by a physical
3241button, a software key, or gestures. This Menu function should be presented
3242unless hidden together with other navigation functions.</p>
3243
3244<p>Android device implementations with the support of the Assist action [<a
3245href="http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST">Resources,
324630</a>] MUST make this accessisble with a single action (e.g. tap, double-click,
3247or gesture) when other navigation keys are visible, and are STRONGLY RECOMMENDED to
3248use the long-press on the Home button or software key as the single action.</p>
3249
3250<p>Device implementations MAY use a distinct portion of the screen to display the
3251navigation keys, but if so, MUST meet these requirements:</p>
3252
3253<ul>
3254 <li>Device implementation navigation keys MUST use a distinct portion of the
3255screen, not available to applications, and MUST NOT obscure or otherwise
3256interfere with the portion of the screen available to applications.</li>
3257 <li>Device implementations MUST make available a portion of the display to
3258applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
3259 <li>Device implementations MUST display the navigation keys when applications do
3260not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
3261 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
3262profile&rdquo; (eg. dimmed) mode when applications specify
3263SYSTEM_UI_FLAG_LOW_PROFILE.</li>
3264 <li>Device implementations MUST hide the navigation keys when applications specify
3265SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
3266</ul>
3267
3268<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
3269
3270<div class="note">
3271<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
3272</div>
3273
3274
3275<p>Device implementations SHOULD have a pointer input system of some kind (either
3276mouse-like or touch). However, if a device implementation does not support a
3277pointer input system, it MUST NOT report the android.hardware.touchscreen or
3278android.hardware.faketouch feature constant. Device implementations that do
3279include a pointer input system:</p>
3280
3281<ul>
3282 <li>SHOULD support fully independently tracked pointers, if the device input system
3283supports multiple pointers.</li>
3284 <li>MUST report the value of android.content.res.Configuration.touchscreen [<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 85</a>] corresponding to the type of the specific touchscreen on the device.</li>
3285</ul>
3286
3287<p>Android includes support for a variety of touchscreens, touch pads, and fake
3288touch input devices. Touchscreen based device implementations are associated
3289with a display [<a href="http://source.android.com/devices/tech/input/touch-devices.html">Resources, 86</a>] such that the user has the impression of directly manipulating items on
3290screen. Since the user is directly touching the screen, the system does not
3291require any additional affordances to indicate the objects being manipulated.
3292In contrast, a fake touch interface provides a user input system that
3293approximates a subset of touchscreen capabilities. For example, a mouse or
3294remote control that drives an on-screen cursor approximates touch, but requires
3295the user to first point or focus then click. Numerous input devices like the
3296mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
3297trackpad can support fake touch interactions. Android includes the feature
3298constant android.hardware.faketouch, which corresponds to a high-fidelity
3299non-touch (pointer-based) input device such as a mouse or trackpad that can
3300adequately emulate touch-based input (including basic gesture support), and
3301indicates that the device supports an emulated subset of touchscreen
3302functionality. Device implementations that declare the fake touch feature MUST
3303meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
3304
3305<p>Device implementations MUST report the correct feature corresponding to the
3306type of input used. Device implementations that include a touchscreen
3307(single-touch or better) MUST report the platform feature constant
3308android.hardware.touchscreen. Device implementations that report the platform
3309feature constant android.hardware.touchscreen MUST also report the platform
3310feature constant android.hardware.faketouch. Device implementations that do not
3311include a touchscreen (and rely on a pointer device only) MUST NOT report any
3312touchscreen feature, and MUST report only android.hardware.faketouch if they
3313meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
3314
3315<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
3316
3317
3318<p>Device implementations that declare support for android.hardware.faketouch:</p>
3319
3320<ul>
3321 <li>MUST report the absolute X and Y screen positions of the pointer location and
3322display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 87</a>].</li>
3323 <li>MUST report touch event with the action code that specifies the state change
3324that occurs on the pointer going down or up on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 87</a>].</li>
3325 <li>MUST support pointer down and up on an object on the screen, which allows users
3326to emulate tap on an object on the screen.</li>
3327 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
3328place on an object on the screen within a time threshold, which allows users to
3329emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 87</a>].</li>
3330 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
3331any other arbitrary point on the screen, followed by a pointer up, which allows
3332users to emulate a touch drag.</li>
3333 <li>MUST support pointer down then allow users to quickly move the object to a
3334different position on the screen and then pointer up on the screen, which
3335allows users to fling an object on the screen.</li>
3336</ul>
3337
3338<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
3339MUST meet the requirements for faketouch above, and MUST also support distinct
3340tracking of two or more independent pointer inputs.</p>
3341
3342<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
3343
3344
3345<p>Android Television device implementations MUST support button mappings for game
3346controllers as listed below. The upstream Android implementation includes
3347implementation for game controllers that satisfies this requirement. </p>
3348
3349<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3350
3351
3352<p>Android Television device implementations MUST support the following key
3353mappings:</p>
3354<table>
3355 <tr>
3356 <th>Button</th>
3357 <th>HID Usage<sup>2</sup></th>
3358 <th>Android Button</th>
3359 </tr>
3360 <tr>
3361 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3362 <td>0x09 0x0001</td>
3363 <td>KEYCODE_BUTTON_A (96)</td>
3364 </tr>
3365 <tr>
3366 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3367 <td>0x09 0x0002</td>
3368 <td>KEYCODE_BUTTON_B (97)</td>
3369 </tr>
3370 <tr>
3371 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3372 <td>0x09 0x0004</td>
3373 <td>KEYCODE_BUTTON_X (99)</td>
3374 </tr>
3375 <tr>
3376 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3377 <td>0x09 0x0005</td>
3378 <td>KEYCODE_BUTTON_Y (100)</td>
3379 </tr>
3380 <tr>
3381 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup><br />
3382
3383<a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_DOWN">D-pad down</a><sup>1</sup></td>
3384 <td>0x01 0x0039<sup>3</sup></td>
3385 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3386 </tr>
3387 <tr>
3388 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1<br />
3389
3390<a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_RIGHT">D-pad right</a><sup>1</sup></td>
3391 <td>0x01 0x0039<sup>3</sup></td>
3392 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3393 </tr>
3394 <tr>
3395 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3396 <td>0x09 0x0007</td>
3397 <td>KEYCODE_BUTTON_L1 (102)</td>
3398 </tr>
3399 <tr>
3400 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3401 <td>0x09 0x0008</td>
3402 <td>KEYCODE_BUTTON_R1 (103)</td>
3403 </tr>
3404 <tr>
3405 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3406 <td>0x09 0x000E</td>
3407 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3408 </tr>
3409 <tr>
3410 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3411 <td>0x09 0x000F</td>
3412 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3413 </tr>
3414 <tr>
3415 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3416 <td>0x0c 0x0223</td>
3417 <td>KEYCODE_HOME (3)</td>
3418 </tr>
3419 <tr>
3420 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3421 <td>0x0c 0x0224</td>
3422 <td>KEYCODE_BACK (4)</td>
3423 </tr>
3424</table>
3425
3426
3427<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 88</a>]</p>
3428
3429<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3430
3431<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3432Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3433Report Size of 4. The logical value is defined to be the clockwise rotation
3434away from the vertical axis; for example, a logical value of 0 represents no
3435rotation and the up button being pressed, while a logical value of 1 represents
3436a rotation of 45 degrees and both the up and left keys being pressed.</p>
3437
3438<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 87</a>]</p>
3439
3440<table>
3441 <tr>
3442 <th>Analog Controls<sup>1</sup></th>
3443 <th>HID Usage</th>
3444 <th>Android Button</th>
3445 </tr>
3446 <tr>
3447 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3448 <td>0x02 0x00C5</td>
3449 <td>AXIS_LTRIGGER </td>
3450 </tr>
3451 <tr>
3452 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3453 <td>0x02 0x00C4</td>
3454 <td>AXIS_RTRIGGER </td>
3455 </tr>
3456 <tr>
3457 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3458 <td>0x01 0x0030<br />
3459
34600x01 0x0031</td>
3461 <td>AXIS_X<br />
3462
3463AXIS_Y</td>
3464 </tr>
3465 <tr>
3466 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3467 <td>0x01 0x0032<br />
3468
34690x01 0x0035</td>
3470 <td>AXIS_Z<br />
3471
3472AXIS_RZ</td>
3473 </tr>
3474</table>
3475
3476
3477<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 87</a>]</p>
3478
3479<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3480
3481
3482<p>Android Television device implementations SHOULD provide a remote control to
3483allow users to access the TV interface. The remote control MAY be a physical
3484remote or can be a software-based remote that is accessible from a mobile phone
3485or tablet. The remote control MUST meet the requirements defined below.</p>
3486
3487<ul>
3488 <li><strong>Search affordance</strong>. Device implementations MUST fire KEYCODE_SEARCH when the user invokes voice search either on the physical or software-based remote.</li>
3489 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3490support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 88</a>].</li>
3491</ul>
3492
3493<h2 id="7_3_sensors">7.3. Sensors</h2>
3494
3495
3496<p>Android includes APIs for accessing a variety of sensor types. Devices
3497implementations generally MAY omit these sensors, as provided for in the
3498following subsections. If a device includes a particular sensor type that has a
3499corresponding API for third-party developers, the device implementation MUST
3500implement that API as described in the Android SDK documentation and the
3501Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 89</a>]. For example, device implementations:</p>
3502
3503<ul>
3504 <li>MUST accurately report the presence or absence of sensors per the
3505android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70]</a>.</li>
3506 <li>MUST return an accurate list of supported sensors via the
3507SensorManager.getSensorList() and similar methods.</li>
3508 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3509true or false as appropriate when applications attempt to register listeners,
3510not calling sensor listeners when the corresponding sensors are not present;
3511etc.).</li>
3512 <li>MUST report all sensor measurements using the relevant International System of
3513Units (metric) values for each sensor type as defined in the Android SDK
3514documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 90</a>].</li>
3515 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3516documentation, representing the time the event happened and synchronized with
3517the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3518are <strong>STRONGLY RECOMMENDED</strong> to meet these requirement so they will be able to upgrade to the future
3519platform releases where this might become a REQUIRED component. The
3520synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 91</a>].</li>
3521 <li>MUST report sensor data with a maximum latency of 100 milliseconds + 2 * sample_time for the case of a sensor streamed
3522 with a minimum required latency of 5 ms + 2 * sample_time when the application processor is active. This delay does not include any filtering delays.</li>
3523 <li>MUST report the first sensor sample within 400 milliseconds + 2 * sample_time of the sensor being activated. It is acceptable for this sample to have an accuracy of 0.</li>
3524</ul>
3525
3526<p>The list above is not comprehensive; the documented behavior of the Android SDK
3527and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 89</a>] is to be considered authoritative.</p>
3528
3529<p>Some sensor types are composite, meaning they can be derived from data provided
3530by one or more other sensors. (Examples include the orientation sensor, and the
3531linear acceleration sensor.) Device implementations SHOULD implement these
3532sensor types, when they include the prerequisite physical sensors as described
3533in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 92</a>].
3534If a device implementation includes a composite sensor it MUST implement the
3535sensor as described in the Android Open Source documentation on composite
3536sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 92</a>].</p>
3537
3538<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3539continuously [<a href="https://source.android.com/devices/sensors/report-modes.html#continuous">Resources, 93</a>]. For any API indicated by the Android SDK documentation to be a continuous
3540sensor, device implementations MUST continuously provide periodic data samples
3541that SHOULD have a jitter below 3%, where jitter is defined as the standard
3542deviation of the difference of the reported timestamp values between
3543consecutive events.</p>
3544
3545<p>Note that the device implementations MUST ensure that the sensor event stream
3546MUST NOT prevent the device CPU from entering a suspend state or waking up from
3547a suspend state.</p>
3548
3549<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3550exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3551
3552<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3553
3554
3555<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3556devices and Android Watch devices are STRONGLY RECOMMENDED to include this
3557sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3558
3559<ul>
3560 <li>MUST implement and report TYPE_ACCELEROMETER sensor [<a href="http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER">Resources, 94</a>].</li>
3561 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3562 Android Watch devices as such devices have a stricter power constraint and
3563 100 Hz for all other device types.</li>
3564 <li>SHOULD report events up to at least 200 Hz.</li>
3565 <li>MUST comply with the Android sensor coordinate system as detailed in the
3566Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 90</a>].</li>
3567 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3568more on any axis.</li>
3569 <li>MUST have a resolution of at least 12-bits and SHOULD have a resolution of at
3570least 16-bits.</li>
3571 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3572cycle and compensated, and preserve the compensation parameters between device
3573reboots.</li>
3574 <li>SHOULD be temperature compensated.</li>
3575 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3576deviation should be calculated on a per axis basis on samples collected over a
3577period of at least 3 seconds at the fastest sampling rate.</li>
3578 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3579TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3580Android SDK document. Existing and new Android devices are <strong>STRONGLY RECOMMENDED</strong> to implement the TYPE_SIGNIFICANT_MOTION composite sensor. If any of these
3581sensors are implemented, the sum of their power consumption MUST always be less
3582than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3583dynamic or static condition.</li>
3584 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3585TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3586TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3587are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3588 <li>MUST implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3589and a magnetometer sensor is also included.</li>
3590</ul>
3591
3592<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3593
3594
3595<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3596device does include a 3-axis magnetometer, it:</p>
3597
3598<ul>
3599 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3600TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3601STRONGLY RECOMMENDED to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3602 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3603report events up to at least 50 Hz.</li>
3604 <li>MUST comply with the Android sensor coordinate system as detailed in the
3605Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 90</a>].</li>
3606 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3607saturating.</li>
3608 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3609below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3610and static (magnet-induced) magnetic fields.</li>
3611 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3612equal or denser than 0.2 &micro;.</li>
3613 <li>SHOULD be temperature compensated.</li>
3614 <li>MUST support online calibration and compensation of the hard iron bias, and
3615preserve the compensation parameters between device reboots.</li>
3616 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3617while in use or during the production of the device.</li>
3618 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3619collected over a period of at least 3 seconds at the fastest sampling rate, no
3620greater than 0.5 &micro;T.</li>
3621 <li>MUST implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3622sensor and a gyroscope sensor is also included.</li>
3623 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3624sensor is also implemented. However if implemented, it MUST consume less than
362510 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3626mode at 10 Hz.</li>
3627</ul>
3628
3629<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3630
3631
3632<p>Device implementations SHOULD include a GPS receiver. If a device
3633implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3634
3635<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3636
3637
3638<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3639Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3640also included. If a device implementation includes a gyroscope, it:</p>
3641
3642<ul>
3643 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3644TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3645STRONGLY RECOMMENDED to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3646 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3647 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3648 Android Watch devices as such devices have a stricter power constraint and
3649 100 Hz for all other device types.</li>
3650 <li>SHOULD report events up to at least 200 Hz.</li>
3651 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
365216-bits or more.</li>
3653 <li>MUST be temperature compensated.</li>
3654 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3655parameters between device reboots.</li>
3656 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3657or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3658be constrained by this value. In other words, if you measure the variance of
3659the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3660 <li>MUST implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3661sensor and a magnetometer sensor is also included.</li>
3662 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3663TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3664TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3665are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3666</ul>
3667
3668<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3669
3670
3671<p>Device implementations SHOULD include a barometer (ambient air pressure
3672sensor). If a device implementation includes a barometer, it:</p>
3673
3674<ul>
3675 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3676 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3677 <li>MUST have adequate precision to enable estimating altitude.</li>
3678 <li>MUST be temperature compensated.</li>
3679</ul>
3680
3681<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3682
3683
3684<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3685If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3686measure the ambient (room) temperature in degrees Celsius.</p>
3687
3688<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3689present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3690temperature of the device CPU, and it MUST NOT measure any other temperature.
3691Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3692
3693<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3694
3695
3696<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3697
3698<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3699
3700
3701<p>Device implementations MAY include a proximity sensor. Devices that can make a
3702voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3703SHOULD include a proximity sensor. If a device implementation does include a
3704proximity sensor, it:</p>
3705
3706<ul>
3707 <li>MUST measure the proximity of an object in the same direction as the screen.
3708That is, the proximity sensor MUST be oriented to detect objects close to the
3709screen, as the primary intent of this sensor type is to detect a phone in use
3710by the user. If a device implementation includes a proximity sensor with any
3711other orientation, it MUST NOT be accessible through this API.</li>
3712 <li>MUST have 1-bit of accuracy or more.</li>
3713</ul>
3714
3715
3716<h3 id="7_3_9_hifi_sensors">7.3.9. High Fidelity Sensors</h3>
3717
3718<p>Device implementations supporting a set of higher quality sensors that can meet all
3719the requirements listed in this section MUST identify the support through the
3720<code>android.hardware.sensor.hifi_sensors</code> feature flag.</p>
3721
3722<p>A device declaring android.hardware.sensor.hifi_sensors MUST support all of the following
3723sensor types meeting the quality requirements as below:</p>
3724
3725<ul>
3726 <li>SENSOR_TYPE_ACCELEROMETER
3727 <ul>
3728 <li>MUST have a measurement range between at least -8g and +8g</li>
3729 <li>MUST have a measurement resolution of at least 1024 LSB/G</li>
3730 <li>MUST have a minimum measurement frequency of 12.5 Hz or lower</li>
3731 <li>MUST have a maxmium measurement frequency of 200 Hz or higher</li>
3732 <li>MUST have a measurement noise not above 400uG/&radic;Hz</li>
3733 <li>MUST implement a non-wake-up form of this sensor with a buffering capability of at least 3000 sensor events</li>
3734 <li>MUST have a batching power consumption not worse than 3 mW</li>
3735 </ul>
3736 </li>
3737 <li>SENSOR_TYPE_GYROSCOPE
3738 <ul>
3739 <li>MUST have a measurement range between at least -1000 and +1000 dps</li>
3740 <li>MUST have a measurement resolution of at least 16 LSB/dps</li>
3741 <li>MUST have a minimum measurement frequency of 12.5 Hz or lower</li>
3742 <li>MUST have a maxmium measurement frequency of 200 Hz or higher</li>
3743 <li>MUST have a measurement noise not above 0.014&deg;/s/&radic;Hz</li>
3744 </ul>
3745 </li>
3746 <li>SENSOR_TYPE_GYROSCOPE_UNCALIBRATED with the same quality requirements as
3747 SENSOR_TYPE_GYROSCOPE</li>
3748 <li>SENSOR_TYPE_GEOMAGNETIC_FIELD
3749 <ul>
3750 <li>MUST have a measurement range between at least -900 and +900 uT</li>
3751 <li>MUST have a measurement resolution of at least 5 LSB/uT</li>
3752 <li>MUST have a minimum measurement frequency of 5 Hz or lower</li>
3753 <li>MUST have a maxmium measurement frequency of 50 Hz or higher</li>
3754 <li>MUST have a measurement noise not above 0.5 uT</li>
3755 </ul>
3756 </li>
3757 <li>SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED with the same quality requirements as
3758 SENSOR_TYPE_GEOMAGNETIC_FIELD and in addition:
3759 <ul>
3760 <li>MUST implement a non-wake-up form of this sensor with a buffering capability of at least 600 sensor events</li>
3761 </ul>
3762 </li>
3763 <li>SENSOR_TYPE_PRESSURE
3764 <ul>
3765 <li>MUST have a measurement range between at least 300 and 1100 hPa</li>
3766 <li>MUST have a measurement resolution of at least 80 LSB/hPa</li>
3767 <li>MUST have a minimum measurement frequency of 1 Hz or lower</li>
3768 <li>MUST have a maximum measurement frequency of 10 Hz or higher</li>
3769 <li>MUST have a measurement noise not above 2 Pa/&radic;Hz</li>
3770 <li>MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events</li>
3771 <li>MUST have a batching power consumption not worse than 2 mW</li>
3772 </ul>
3773 </li>
3774 <li>SENSOR_TYPE_ROTATION_VECTOR
3775 <ul>
3776 <li>MUST have a batching power consumption not worse than 4 mW</li>
3777 </ul>
3778 </li>
3779 <li>SENSOR_TYPE_GAME_ROTATION_VECTOR MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events</li>
3780 <li>SENSOR_TYPE_SIGNIFICANT_MOTION
3781 <ul>
3782 <li>MUST have a power consumption not worse than 0.5 mW when device is static
3783 and 1.5 mW when device is moving</li>
3784 </ul>
3785 </li>
3786 <li>SENSOR_TYPE_STEP_DETECTOR
3787 <ul>
3788 <li>MUST implement a non-wake-up form of this sensor with a buffering capability of at least 100 sensor events</li>
3789 <li>MUST have a power consumption not worse than 0.5 mW when device is static
3790 and 1.5 mW when device is moving</li>
3791 <li>MUST have a batching power consumption not worse than 4 mW</li>
3792 </ul>
3793 </li>
3794 <li>SENSOR_TYPE_STEP_COUNTER
3795 <ul>
3796 <li>MUST have a power consumption not worse than 0.5 mW when device is static
3797 and 1.5 mW when device is moving</li>
3798 </ul>
3799 </li>
3800 <li>SENSOR_TILT_DETECTOR
3801 <ul>
3802 <li>MUST have a power consumption not worse than 0.5 mW when device is static
3803 and 1.5 mW when device is moving</li>
3804 </ul>
3805 </li>
3806</ul>
3807
3808<p>Also such a device MUST meet the following sensor subsystem requirements:</p>
3809
3810<ul>
3811 <li>The event timestamp of the same physical event reported by the Accelerometer, Gyroscope
3812 sensor and Magnetometer MUST be within 2.5 milliseconds of each other.</li>
3813 <li>The Gyroscope sensor event timestamps MUST be on the same time base as the camera
3814 subsystem and within 1 millisconds of error.</li>
3815 <li>The latency of delivery of samples to the HAL SHOULD be below 5 milliseconds from
3816 the instant the data is available on the physical sensor hardware.</li>
3817 <li>The power consumption MUST not be higher than 0.5 mW when device is static and 2.0 mW
3818 when device is moving when any combination of the following sensors are enabled:
3819 <ul>
3820 <li>SENSOR_TYPE_SIGNIFICANT_MOTION</li>
3821 <li>SENSOR_TYPE_STEP_DETECTOR</li>
3822 <li>SENSOR_TYPE_STEP_COUNTER</li>
3823 <li>SENSOR_TILT_DETECTORS</li>
3824 </ul>
3825 </li>
3826</ul>
3827
3828<p>Note that all power consumption requirements in this section do not include the power
3829 consumption of the Application Processor. It is inclusive of the power drawn by the entire
3830 sensor chain - the sensor, any supporting circuitry, any dedicated sensor processing system,
3831 etc.</p>
3832
3833<p>The following sensor types MAY also be supported on a device implementation declaring
3834 android.hardware.sensor.hifi_sensors, but if these sensor types are present they MUST meet the
3835 following minimum buffering capability requirement:</p>
3836
3837<ul>
3838 <li>SENSOR_TYPE_PROXIMITY: 100 sensor events</li>
3839</ul>
3840
3841<h3 id="7_3_10_fingeprint">7.3.10. Fingerprint Sensor</h3>
3842
3843<p>Device implementations with a secure lock screen SHOULD include a fingerprint sensor.
3844If a device implementation includes a fingerprint sensor and has a corresponding API for
3845third-party developers, it:</p>
3846
3847<ul>
3848 <li>MUST declare support for the android.hardware.fingerprint feature.</li>
3849 <li>MUST fully implement the corresponding API as described in the Android SDK documentation
3850[<a href="https://developer.android.com/reference/android/hardware/fingerprint/package-summary.html">Resources, 95</a>].
3851 </li>
3852 <li>MUST have a false acceptance rate not higher than 0.002%.</li>
3853 <li>Is STRONGLY RECOMMENDED to have a false rejection rate not higher than 10%, and a
3854 latency from when the fingerprint sensor is touched until the screen is unlocked below
3855 1 second, for 1 enrolled finger.</li>
3856 <li>MUST rate limit attempts for at least 30 seconds after 5 false trials for fingerprint
3857 verification.</li>
3858 <li>MUST have a hardware-backed keystore implementation, and perform the fingerprint matching
3859 in a Trusted Execution Environment (TEE) or on a chip with a secure channel to the TEE.
3860 </li>
3861 <li>MUST have all identifiable fingerprint data encrypted and cryptographically
3862 authenticated such that they cannot be acquired, read or altered outside of the
3863 Trusted Execution Environment (TEE) as documented in the implementation guidelines
3864 on the Android Open Source Project site
3865 [<a href="https://source.android.com/devices/tech/security/authentication/fingerprint-hal.html">Resources, 96</a>].
3866 </li>
3867 <li>MUST prevent adding a fingerprint without first establishing a chain of trust by
3868 having the user confirm existing or add a new device credential (PIN/pattern/password)
3869 using the TEE as implemented in the Android Open Source project.</li>
3870 <li>MUST NOT enable 3rd-party applications to distinguish between individual fingerprints.
3871 </li>
3872 <li>MUST honor the DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT flag.</li>
3873 <li>MUST, when upgraded from a version earlier than Android 6.0, have the fingerprint
3874 data securely migrated to meet the above requirements or removed.</li>
3875 <li>SHOULD use the Android Fingerprint icon provided in the Android Open Source Project.</li>
3876</ul>
3877
3878<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3879
3880
3881<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3882
3883
3884<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3885to hardware related to placing voice calls and sending SMS messages via a GSM
3886or CDMA network. While these voice calls may or may not be packet-switched,
3887they are for the purposes of Android considered independent of any data
3888connectivity that may be implemented using the same network. In other words,
3889the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3890calls and SMS. For instance, device implementations that cannot place calls or
3891send/receive SMS messages MUST NOT report the android.hardware.telephony
3892feature or any subfeatures, regardless of whether they use a cellular network
3893for data connectivity.</p>
3894
3895<p>Android MAY be used on devices that do not include telephony hardware. That is,
3896Android is compatible with devices that are not phones. However, if a device
3897implementation does include GSM or CDMA telephony, it MUST implement full
3898support for the API for that technology. Device implementations that do not
3899include telephony hardware MUST implement the full APIs as no-ops.</p>
3900
3901<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3902
3903<div class="note">
3904<p>Android Television device implementations MUST include Wi-Fi support.</p>
3905</div>
3906
3907
3908<p>Android Television device implementations MUST include support for one or more
3909forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3910implementation SHOULD include support for one or more forms of 802.11. If a
3911device implementation does include support for 802.11 and exposes the
3912functionality to a third-party application, it MUST implement the corresponding
3913Android API and:</p>
3914
3915<ul>
3916 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3917 <li>MUST implement the multicast API as described in the SDK documentation [<a href="http://developer.android.com/reference/android/net/wifi/WifiManager.MulticastLock.html">Resources, 97</a>].</li>
3918 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3919(224.0.0.251) at any time of operation including:
3920 <ul>
3921 <li>Even when the screen is not in an active state.</li>
3922 <li>For Android Television device implementations, even when in standby power states.</li>
3923 </ul>
3924</ul>
3925
3926<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3927
3928
3929<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3930peer-to-peer). If a device implementation does include support for Wi-Fi
3931Direct, it MUST implement the corresponding Android API as described in the SDK
3932documentation [<a href="http://developer.android.com/reference/android/net/wifi/p2p/WifiP2pManager.html">Resources, 98</a>]. If a device implementation includes support for Wi-Fi Direct, then it:</p>
3933
3934<ul>
3935 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3936 <li>MUST support regular Wi-Fi operation.</li>
3937 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3938</ul>
3939
3940<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3941
3942<div class="note">
3943<p>Android Television device implementations MUST include support for Wi-Fi
3944Tunneled Direct Link Setup (TDLS).</p>
3945</div>
3946
3947
3948<p>Android Television device implementations MUST include support for Wi-Fi
3949Tunneled Direct Link Setup (TDLS) and other types of Android device
3950implementations SHOULD include support for Wi-Fi TDLS as described in the
3951Android SDK Documentation [<a href="http://developer.android.com/reference/android/net/wifi/WifiManager.html">Resources, 99</a>]. If a device implementation does include support for TDLS and TDLS is enabled
3952by the WiFiManager API, the device:</p>
3953
3954<ul>
3955 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3956 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3957than going through the Wi-Fi access point.</li>
3958</ul>
3959
3960<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3961
3962<div class="note">
3963<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3964Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3965</div>
3966
3967
3968<p>Android includes support for Bluetooth and Bluetooth Low Energy [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 100</a>]. Device implementations that include support for Bluetooth and Bluetooth Low
3969Energy MUST declare the relevant platform features (android.hardware.bluetooth
3970and android.hardware.bluetooth_le respectively) and implement the platform
3971APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3972as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3973device implementations MUST support Bluetooth and Bluetooth LE. </p>
3974
3975<p>Device implementations including support for Bluetooth Low Energy:</p>
3976
3977<ul>
3978 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3979 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3980described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 100</a>].</li>
3981 <li>MUST implement a Resolvable Private Address (RPA) timeout no longer than
398215 minutes, and rotate the address at timeout to protect user privacy.</li>
3983 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3984implementing the ScanFilter API [<a href="https://developer.android.com/reference/android/bluetooth/le/ScanFilter.html">Resources, 101</a>], and MUST report the correct value of where the filtering logic is implemented whenever queried via the
3985android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3986 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3987if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3988android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3989 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3990MUST report &lsquo;false&rsquo; whenever queried via the
3991android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3992</ul>
3993
3994<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3995
3996
3997<p>Device implementations SHOULD include a transceiver and related hardware for
3998Near-Field Communications (NFC). If a device implementation does include NFC
3999hardware and plans to make it available to third-party apps, then it:</p>
4000
4001<ul>
4002 <li>MUST report the android.hardware.nfc feature from the
4003android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>].</li>
4004 <li>MUST be capable of reading and writing NDEF messages via the following NFC
4005standards:
4006 <ul>
4007 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
4008Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
4009following NFC standards:
4010 <ul>
4011 <li>NfcA (ISO14443-3A)</li>
4012 <li>NfcB (ISO14443-3B)</li>
4013 <li>NfcF (JIS X 6319-4)</li>
4014 <li>IsoDep (ISO 14443-4)</li>
4015 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
4016 </ul>
4017 <li>STRONGLY RECOMMENDED to be capable of reading and writing NDEF messages as well
4018 as raw data via the following NFC standards. Note that while the NFC standards
4019 below are stated as STRONGLY RECOMMENDED, the Compatibility Definition for a
4020 future version is planned to change these to MUST. These standards are optional
4021 in this version but will be required in future versions. Existing and new devices
4022 that run this version of Android are very strongly encouraged to meet these
4023 requirements now so they will be able to upgrade to the future platform releases.
4024 <ul>
4025 <li>NfcV (ISO 15693)</li>
4026 </ul></li>
4027 <li>SHOULD be capable of reading the barcode and URL (if encoded) of
4028 Thinfilm NFC Barcode
4029 [<a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">Resources, 102</a>] products.
4030 </li>
4031 <li>MUST be capable of transmitting and receiving data via the following
4032peer-to-peer standards and protocols:
4033 <ul>
4034 <li>ISO 18092</li>
4035 <li>LLCP 1.2 (defined by the NFC Forum)</li>
4036 <li>SDP 1.0 (defined by the NFC Forum)</li>
4037 <li>NDEF Push Protocol [<a href="http://static.googleusercontent.com/media/source.android.com/en/us/compatibility/ndef-push-protocol.pdf">Resources, 103</a>]</li>
4038 <li>SNEP 1.0 (defined by the NFC Forum)</li>
4039 </ul></li>
4040 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 104</a>]:
4041 <ul>
4042 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
4043default SNEP server MUST be dispatched to applications using the
4044android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
4045MUST NOT disable dispatch of incoming NDEF message.</li>
4046 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
4047settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 105</a>].</li>
4048 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
4049processed the same way as the SNEP default server.</li>
4050 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
4051default SNEP server when Android Beam is enabled. If no default SNEP server is
4052found then the client MUST attempt to send to an NPP server.</li>
4053 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
4054android.nfc.NfcAdapter.setNdefPushMessage, and
4055android.nfc.NfcAdapter.setNdefPushMessageCallback, and
4056android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
4057 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
4058sending outbound P2P NDEF messages.</li>
4059 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
4060using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
4061 <li>MUST support NFC Connection handover to Bluetooth when the device supports
4062Bluetooth Object Push Profile. Device implementations MUST support connection
4063handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
4064implementing the &ldquo;Connection Handover version 1.2&rdquo; [<a href="http://members.nfc-forum.org/specs/spec_list/#conn_handover">Resources, 106</a>] and &ldquo;Bluetooth Secure Simple Pairing Using NFC version 1.0&rdquo; [<a href="http://members.nfc-forum.org/apps/group_public/download.php/18688/NFCForum-AD-BTSSP_1_1.pdf">Resources, 107</a>] specs from the NFC Forum. Such an implementation MUST implement the handover
4065LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
4066handover request/select records over NFC, and it MUST use the Bluetooth Object
4067Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
4068remain compatible with Android 4.1 devices), the implementation SHOULD still
4069accept SNEP GET requests for exchanging the handover request/select records
4070over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
4071for performing connection handover.</li>
4072 </ul></li>
4073 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
4074 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
4075active and the lock-screen unlocked.</li>
4076</ul>
4077</ul>
4078
4079<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
4080Forum specifications cited above.)</p>
4081
4082<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
4083device implementation does include an NFC controller chipset capable of HCE and
4084Application ID (AID) routing, then it:</p>
4085
4086<ul>
4087 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
4088 <li>MUST support NFC HCE APIs as defined in the Android SDK [<a href="http://developer.android.com/guide/topics/connectivity/nfc/hce.html">Resources, 108</a>].</li>
4089</ul>
4090
4091<p>Additionally, device implementations MAY include reader/writer support for the
4092following MIFARE technologies.</p>
4093
4094<ul>
4095 <li>MIFARE Classic</li>
4096 <li>MIFARE Ultralight</li>
4097 <li>NDEF on MIFARE Classic</li>
4098</ul>
4099
4100<p>Note that Android includes APIs for these MIFARE types. If a device
4101implementation supports MIFARE in the reader/writer role, it:</p>
4102
4103<ul>
4104 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
4105 <li>MUST report the feature com.nxp.mifare from the
4106android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>]. Note that this is not a standard Android feature and as such does not appear
4107as a constant in the android.content.pm.PackageManager class.</li>
4108 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
4109feature unless it also implements general NFC support as described in this
4110section.</li>
4111</ul>
4112
4113<p>If a device implementation does not include NFC hardware, it MUST NOT declare
4114the android.hardware.nfc feature from the
4115android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 70</a>], and MUST implement the Android NFC API as a no-op.</p>
4116
4117<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
4118protocol-independent data representation format, device implementations MUST
4119implement these APIs even if they do not include support for NFC or declare the
4120android.hardware.nfc feature.</p>
4121
4122<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
4123
4124
4125<p>Device implementations MUST include support for one or more forms of data
4126networking. Specifically, device implementations MUST include support for at
4127least one data standard capable of 200Kbit/sec or greater. Examples of
4128technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
4129Ethernet, Bluetooth PAN, etc.</p>
4130
4131<p>Device implementations where a physical networking standard (such as Ethernet)
4132is the primary data connection SHOULD also include support for at least one
4133common wireless data standard, such as 802.11 (Wi-Fi).</p>
4134
4135<p>Devices MAY implement more than one form of data connectivity.</p>
4136
4137<p>Devices MUST include an IPv6 networking stack and support IPv6 communication
4138using the managed APIs, such as <code>java.net.Socket</code> and
4139<code>java.net.URLConnection</code>, as well as the native APIs, such as
4140<code>AF_INET6</code> sockets. The required level of IPv6 support depends on
4141the network type, as follows:</p>
4142<ul>
4143 <li>Devices that support Wi-Fi networks MUST support dual-stack and IPv6-only
4144 operation on Wi-Fi.</li>
4145 <li>Devices that support Ethernet networks MUST support dual-stack operation
4146 on Ethernet.</li>
4147 <li>Devices that support cellular data SHOULD support IPv6 operation
4148 (IPv6-only and possibly dual-stack) on cellular data.</li>
4149 <li>When a device is simultaneously connected to more than one network (e.g.,
4150 Wi-Fi and cellular data), it MUST simultaneously meet these requirements on
4151 each network to which it is connected.</li>
4152</ul>
4153
4154<p>IPv6 MUST be enabled by default.</p>
4155
4156<p>In order to ensure that IPv6 communication is as reliable as IPv4, unicast
4157IPv6 packets sent to the device MUST NOT be dropped, even when the screen is
4158not in an active state. Redundant multicast IPv6 packets, such as repeated
4159identical Router Advertisements, MAY be rate-limited in hardware or firmware
4160if doing so is necessary to save power. In such cases, rate-limiting MUST NOT
4161cause the device to lose IPv6 connectivity on any IPv6-compliant network that
4162uses RA lifetimes of at least 180 seconds.</p>
4163
4164<p>IPv6 connectivity MUST be maintained in doze mode.</p>
4165
4166<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
4167
4168
4169<p>Device implementations MUST have the master auto-sync setting on by default so
4170that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 109</a>].</p>
4171
4172<h2 id="7_5_cameras">7.5. Cameras</h2>
4173
4174
4175<p>Device implementations SHOULD include a rear-facing camera and MAY include a
4176front-facing camera. A rear-facing camera is a camera located on the side of
4177the device opposite the display; that is, it images scenes on the far side of
4178the device, like a traditional camera. A front-facing camera is a camera
4179located on the same side of the device as the display; that is, a camera
4180typically used to image the user, such as for video conferencing and similar
4181applications.</p>
4182
4183<p>If a device implementation includes at least one camera, it SHOULD be possible
4184for an application to simultaneously allocate 3 bitmaps equal to the size of
4185the images produced by the largest-resolution camera sensor on the device.</p>
4186
4187<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
4188
4189
4190<p>Device implementations SHOULD include a rear-facing camera. If a device
4191implementation includes at least one rear-facing camera, it:</p>
4192
4193<ul>
4194 <li>MUST report the feature flag android.hardware.camera and
4195android.hardware.camera.any.</li>
4196 <li>MUST have a resolution of at least 2 megapixels.</li>
4197 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
4198the camera driver (transparent to application software).</li>
4199 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
4200 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
4201lit while an android.hardware.Camera.PreviewCallback instance has been
4202registered on a Camera preview surface, unless the application has explicitly
4203enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
4204of a Camera.Parameters object. Note that this constraint does not apply to the
4205device&rsquo;s built-in system camera application, but only to third-party
4206applications using Camera.PreviewCallback.</li>
4207</ul>
4208
4209<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
4210
4211
4212<p>Device implementations MAY include a front-facing camera. If a device
4213implementation includes at least one front-facing camera, it:</p>
4214
4215<ul>
4216 <li>MUST report the feature flag android.hardware.camera.any and
4217android.hardware.camera.front.</li>
4218 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
4219 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
4220camera API in Android has specific support for front-facing cameras and device
4221implementations MUST NOT configure the API to to treat a front-facing camera as
4222the default rear-facing camera, even if it is the only camera on the device.</li>
4223 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
4224cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
4225 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
4226CameraPreview, as follows:
4227 <ul>
4228 <li>If the device implementation is capable of being rotated by user (such as
4229automatically via an accelerometer or manually via user input), the camera
4230preview MUST be mirrored horizontally relative to the device&rsquo;s current
4231orientation.</li>
4232 <li>If the current application has explicitly requested that the Camera display be
4233rotated via a call to the android.hardware.Camera.setDisplayOrientation()[<a href="http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)">Resources, 110</a>] method, the camera preview MUST be mirrored horizontally relative to the
4234orientation specified by the application.</li>
4235 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
4236axis.</li>
4237 </ul></li>
4238 <li>MUST mirror the image displayed by the postview in the same manner as the
4239camera preview image stream. If the device implementation does not support
4240postview, this requirement obviously does not apply.</li>
4241 <li>MUST NOT mirror the final captured still image or video streams returned to
4242application callbacks or committed to media storage.</li>
4243</ul>
4244
4245<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
4246
4247
4248<p>Device implementations with USB host mode MAY include support for an external
4249camera that connects to the USB port. If a device includes support for an
4250external camera, it:</p>
4251
4252<ul>
4253 <li>MUST declare the platform feature android.hardware.camera.external and
4254android.hardware camera.any.</li>
4255 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
4256 <li>MAY support multiple cameras.</li>
4257</ul>
4258
4259<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
4260high-quality unencoded streams (i.e. raw or independently compressed picture
4261streams). Camera-based video encoding MAY be supported. If so, a simultaneous
4262unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
4263device implementation.</p>
4264
4265<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
4266
4267
4268<p>Android includes two API packages to access the camera, the newer
4269android.hardware.camera2 API expose lower-level camera control to the app,
4270including efficient zero-copy burst/streaming flows and per-frame controls of
4271exposure, gain, white balance gains, color conversion, denoising, sharpening,
4272and more.</p>
4273
4274<p>The older API package, android.hardware.Camera, is marked as deprecated in
4275Android 5.0 but as it should still be available for apps to use Android device
4276implementations MUST ensure the continued support of the API as described in
4277this section and in the Android SDK.</p>
4278
4279<p>Device implementations MUST implement the following behaviors for the
4280camera-related APIs, for all available cameras:</p>
4281
4282<ul>
4283 <li>If an application has never called
4284android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
4285use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
4286application callbacks.</li>
4287 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
4288and the system calls the onPreviewFrame() method when the preview format is
4289YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
4290be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
4291 <li>For android.hardware.Camera, device implementations MUST support the YV12
4292format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
4293camera previews for both front- and rear-facing cameras. (The hardware video
4294encoder and camera may use any native pixel format, but the device
4295implementation MUST support conversion to YV12.)</li>
4296 <li>For android.hardware.camera2, device implementations must support the
4297android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
4298formats as outputs through the android.media.ImageReader API.</li>
4299</ul>
4300
4301<p>Device implementations MUST still implement the full Camera API included in the
4302Android SDK documentation [<a href="http://developer.android.com/reference/android/hardware/Camera.html">Resources, 111</a>],
4303regardless of whether the device includes hardware autofocus or other
4304capabilities. For instance, cameras that lack autofocus MUST still call any
4305registered android.hardware.Camera.AutoFocusCallback instances (even though
4306this has no relevance to a non-autofocus camera.) Note that this does apply to
4307front-facing cameras; for instance, even though most front-facing cameras do
4308not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
4309
4310<p>Device implementations MUST recognize and honor each parameter name defined as
4311a constant on the android.hardware.Camera.Parameters class, if the underlying
4312hardware supports the feature. If the device hardware does not support a
4313feature, the API must behave as documented. Conversely, device implementations
4314MUST NOT honor or recognize string constants passed to the
4315android.hardware.Camera.setParameters() method other than those documented as
4316constants on the android.hardware.Camera.Parameters. That is, device
4317implementations MUST support all standard Camera parameters if the hardware
4318allows, and MUST NOT support custom Camera parameter types. For instance,
4319device implementations that support image capture using high dynamic range
4320(HDR) imaging techniques MUST support camera parameter Camera.SCENE_MODE_HDR [<a href="http://developer.android.com/reference/android/hardware/Camera.Parameters.html">Resources, 112</a>].</p>
4321
4322<p>Because not all device implementations can fully support all the features of
4323the android.hardware.camera2 API, device implementations MUST report the proper
4324level of support with the android.info.supportedHardwareLevel property as
4325described in the Android SDK [<a href="https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html#INFO_SUPPORTED_HARDWARE_LEVEL">Resources, 113</a>] and report the appropriate framework feature flags [<a href="http://source.android.com/devices/camera/versioning.html">Resources, 114</a>].</p>
4326
4327<p>Device implementations MUST also declare its Individual camera capabilities of
4328android.hardware.camera2 via the android.request.availableCapabilities property
4329and declare the appropriate feature flags [<a href="http://source.android.com/devices/camera/versioning.html">Resources, 114</a>]; a device must define the feature flag if any of its attached camera devices supports the feature.</p>
4330
4331<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
4332whenever a new picture is taken by the camera and the entry of the picture has
4333been added to the media store.</p>
4334
4335<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
4336whenever a new video is recorded by the camera and the entry of the picture has
4337been added to the media store.</p>
4338
4339<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
4340
4341
4342<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
4343long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
4344when the device is held in the landscape orientation, cameras MUST capture
4345images in the landscape orientation. This applies regardless of the device&rsquo;s
4346natural orientation; that is, it applies to landscape-primary devices as well
4347as portrait-primary devices.</p>
4348
4349<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
4350
4351
4352<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
4353
4354<div class="note">
4355<p>Android Television devices MUST have at least 5GB of non-volatile storage
4356available for application private data.</p>
4357</div>
4358
4359
4360<p>The memory available to the kernel and userspace on device implementations MUST
4361be at least equal or larger than the minimum values specified by the following
4362table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
4363<table>
4364 <tr>
4365 <th>Density and screen size</th>
4366 <th>32-bit device</th>
4367 <th>64-bit device</th>
4368 </tr>
4369 <tr>
4370 <td>Android Watch devices (due to smaller screens)</td>
4371 <td>416MB</td>
4372 <td>Not applicable</td>
4373 </tr>
4374 <tr>
4375 <td><ul>
4376 <li class="table_list">280dpi or lower on small/normal screens</li>
4377 <li class="table_list">mdpi or lower on large screens</li>
4378 <li class="table_list">ldpi or lower on extra large screens</li>
4379 </ul></td>
4380 <td>424MB</td>
4381 <td>704MB</td>
4382 </tr>
4383 <tr>
4384 <td><ul>
4385 <li class="table_list">xhdpi or higher on small/normal screens</li>
4386 <li class="table_list">hdpi or higher on large screens</li>
4387 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
4388 <td>512MB</td>
4389 <td>832MB</td>
4390 </tr>
4391 <tr>
4392 <td><ul>
4393 <li class="table_list">400dpi or higher on small/normal screens</li>
4394 <li class="table_list">xhdpi or higher on large screens</li>
4395 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
4396 <td>896MB</td>
4397 <td>1280MB</td>
4398 </tr>
4399 <tr>
4400 <td><ul>
4401 <li class="table_list">560dpi or higher on small/normal screens</li>
4402 <li class="table_list">400dpi or higher on large screens</li>
4403 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
4404 <td>1344MB</td>
4405 <td>1824MB</td>
4406 </tr>
4407</table>
4408
4409
4410<p>The minimum memory values MUST be in addition to any memory space already
4411dedicated to hardware components such as radio, video, and so on that is not
4412under the kernel&rsquo;s control.</p>
4413
4414<p>Device implementations with less than 512MB of memory available to the kernel
4415and userspace, unless an Android Watch, MUST return the value "true" for
4416ActivityManager.isLowRamDevice().</p>
4417
4418<p>Android Television devices MUST have at least 5GB and other device
4419implementations MUST have at least 1.5GB of non-volatile storage available for
4420application private data. That is, the /data partition MUST be at least 5GB for
4421Android Television devices and at least 1.5GB for other device implementations.
4422Device implementations that run Android are <strong>STRONGLY RECOMMENDED</strong> to have at least 3GB of non-volatile storage for application private data so
4423they will be able to upgrade to the future platform releases.</p>
4424
4425<p>The Android APIs include a Download Manager that applications MAY use to
4426download data files [<a href="http://developer.android.com/reference/android/app/DownloadManager.html">Resources, 115</a>]. The device implementation of the Download Manager MUST be capable of
4427downloading individual files of at least 100MB in size to the default &ldquo;cache"
4428location.</p>
4429
4430<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
4431
4432
4433<p>Device implementations MUST offer shared storage for applications also often
4434referred as &ldquo;shared external storage&rdquo;. </p>
4435
4436<p>Device implementations MUST be configured with shared storage mounted by
4437default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
4438path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
4439to the actual mount point.</p>
4440
4441<p>Device implementations MAY have hardware for user-accessible removable storage,
4442such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
4443shared storage requirement, the device implementation:</p>
4444
4445<ul>
4446 <li>MUST implement a toast or pop-up user interface warning the user when there is
4447no SD card.</li>
4448 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
4449and other material available at time of purchase that the SD card has to be
4450separately purchased.</li>
4451 <li>MUST mount the SD card by default.</li>
4452</ul>
4453
4454<p>Alternatively, device implementations MAY allocate internal (non-removable)
4455storage as shared storage for apps as included in the upstream Android Open
4456Source Project; device implementations SHOULD use this configuration and
4457software implementation. If a device implementation uses internal
4458(non-removable) storage to satisfy the shared storage requirement, that storage
4459MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
4460symbolic link to the physical location if it is mounted elsewhere).</p>
4461
4462<p>Device implementations MUST enforce as documented the
4463android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
4464Shared storage MUST otherwise be writable by any application that obtains that
4465permission.</p>
4466
4467<p>Device implementations that include multiple shared storage paths (such as both
4468an SD card slot and shared internal storage) MUST NOT allow Android
4469applications to write to the secondary external storage, except for their
4470package-specific directories on the secondary external storage, but SHOULD
4471expose content from both storage paths transparently through Android&rsquo;s media
4472scanner service and android.provider.MediaStore.</p>
4473
4474<p>Regardless of the form of shared storage used, if the device implementation
4475has a USB port with USB peripheral mode support, it MUST provide some mechanism
4476to access the contents of shared storage from a host computer. Device
4477implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
4478to satisfy this requirement. If the device implementation supports Media
4479Transfer Protocol, it:</p>
4480
4481<ul>
4482 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
4483[<a href="http://www.android.com/filetransfer">Resources, 116</a>].</li>
4484 <li>SHOULD report a USB device class of 0x00.</li>
4485 <li>SHOULD report a USB interface name of 'MTP'.</li>
4486</ul>
4487
4488<h3 id="7_6_3_adoptable_storage">7.6.3. Adoptable Storage</h3>
4489
4490<p>Device implementations are STRONGLY RECOMMENDED to implement adoptable
4491storage if the removable storage device port is in a long-term stable location,
4492such as within the battery compartment or other protective cover
4493[<a
4494href="http://source.android.com/devices/storage/adoptable.html">Resources,
4495117</a>].</p>
4496
4497<p>Device implementations such as a television, MAY enable adoption through USB
4498ports as the device is expected to be static and not mobile. But for other
4499device implementations that are mobile in nature, it is STRONGLY RECOMMENDED to
4500implement the adoptable storage in a long-term stable location, since accidentally
4501disconnecting them can cause data loss/corruption.</p>
4502
4503<h2 id="7_7_usb">7.7. USB</h2>
4504
4505
4506<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
4507USB host mode.</p>
4508
4509<p>If a device implementation includes a USB port supporting peripheral mode:</p>
4510
4511<ul>
4512 <li>The port MUST be connectable to a USB host that has a standard type-A or type
4513-C USB port.</li>
4514 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
4515new Android devices are <strong>STRONGLY RECOMMENDED to meet these requirements</strong> so they will be able to upgrade to the future platform releases.</li>
4516 <li>The port SHOULD be centered in the middle of an edge. Device implementations
4517SHOULD either locate the port on the bottom of the device (according to natural
4518orientation) or enable software screen rotation for all apps (including home
4519screen), so that the display draws correctly when the device is oriented with
4520the port at bottom. Existing and new Android devices are <strong>STRONGLY RECOMMENDED to meet these requirements</strong> so they will be able to upgrade to future platform releases.</li>
4521 <li>It MUST allow a USB host connected with the Android device to access the
4522contents of the shared storage volume using either USB mass storage or Media
4523Transfer Protocol.</li>
4524 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
4525documented in the Android SDK documentation, and if it is an Android Handheld
4526device it MUST implement the AOA API. Device implementations implementing the
4527AOA specification:
4528 <ul>
4529 <li>MUST declare support for the hardware feature android.hardware.usb.accessory [<a href="http://developer.android.com/guide/topics/connectivity/usb/accessory.html">Resources, 118</a>].</li>
4530 <li>MUST implement the USB audio class as documented in the Android SDK
4531documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 119</a>].</li>
4532 <li>And also the USB mass storage class, MUST include the string "android"
4533at the end of the interface description <code>iInterface</code> string of the
4534USB mass storage</li>
4535 </ul>
4536 </li>
4537 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
4538as specified in the USB battery charging specification [<a href="http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf">Resources, 120</a>]. Existing and new Android devices are <strong>STRONGLY RECOMMENDED to meet these requirements</strong> so they will be able to upgrade to the future platform releases.</li>
4539 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
4540the value of android.os.Build.SERIAL.</li>
4541</ul>
4542
4543<p>If a device implementation includes a USB port supporting host mode, it:</p>
4544
4545<ul>
4546 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
4547 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
4548cables adapting the port to a standard type-A or type-C USB port.</li>
4549 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
4550adapting the port to a standard type-A or type-C USB port.</li>
4551 <li>is <strong>STRONGLY RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
4552documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 119</a>].</li>
4553 <li>MUST implement the Android USB host API as documented in the Android SDK, and
4554MUST declare support for the hardware feature android.hardware.usb.host [<a href="http://developer.android.com/guide/topics/connectivity/usb/host.html">Resources, 121</a>].</li>
4555 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
4556as specified in the USB Battery Charging Specifications [<a href="http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf">Resources, 120</a>].</li>
4557</ul>
4558
4559<h2 id="7_8_audio">7.8. Audio</h2>
4560
4561
4562<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
4563
4564<div class="note">
4565<p>Android Handheld, Watch, and Automotive implementations MUST include a
4566microphone.</p>
4567</div>
4568
4569
4570<p>Device implementations MAY omit a microphone. However, if a device
4571implementation omits a microphone, it MUST NOT report the
4572android.hardware.microphone feature constant, and MUST implement the audio
4573recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>.
4574Conversely, device implementations that do possess a microphone:</p>
4575
4576<ul>
4577 <li>MUST report the android.hardware.microphone feature constant</li>
4578 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a></li>
4579 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a></li>
4580 <li>STRONGLY RECOMMENDED to support near-ultrasound recording as described in
4581 <a href="#7_8_3_near_ultrasound">section 7.8.3</a></li>
4582</ul>
4583
4584<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4585
4586<div class="note">
4587<p>Android Watch devices MAY include an audio output.</p>
4588</div>
4589
4590<p>Device implementations including a speaker or with an audio/multimedia output
4591port for an audio output peripheral as a headset or an external speaker:</p>
4592
4593<ul>
4594 <li>MUST report the android.hardware.audio.output feature constant.</li>
4595 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4596 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4597 <li>STRONGLY RECOMMENDED to support near-ultrasound playback as described in
4598 <a href="#7_8_3_near_ultrasound">section 7.8.3</a></li>
4599</ul>
4600
4601<p>Conversely, if a device implementation does not include a speaker or audio
4602output port, it MUST NOT report the android.hardware.audio output feature, and
4603MUST implement the Audio Output related APIs as no-ops at least. </p>
4604
4605<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4606other types of Android device implementations MUST have an audio output and
4607declare android.hardware.audio.output.</p>
4608
4609<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4610
4611
4612<p>In order to be compatible with the headsets and other audio accessories using
4613the 3.5mm audio plug across the Android ecosystem [<a href="http://source.android.com/accessories/headset-spec.html">Resources, 122</a>], if a device implementation includes one or more analog audio ports, at least
4614one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4615implementation has a 4 conductor 3.5mm audio jack, it:</p>
4616
4617<ul>
4618 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4619microphone, and SHOULD support audio recording from stereo headsets with a
4620microphone.</li>
4621 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4622audio plugs with the OMTP pin-out order.</li>
4623 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4624the device implementation supports a microphone, and broadcast the
4625android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4626 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4627ranges of equivalent impedance between the microphone and ground conductors on
4628the audio plug:
4629 <ul>
4630 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
4631 <li><strong>210&#45;290 Ohm</strong>: KEYCODE_VOLUME_UP</li>
4632 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4633 </ul></li>
4634 <li>SHOULD support the detection and mapping to the keycode for the following range
4635of equivalent impedance between the microphone and ground conductors on the
4636audio plug:
4637 <ul>
4638 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4639 </ul></li>
4640 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4641contacts on plug are touching their relevant segments on the jack.</li>
4642 <li>MUST be capable of driving at least 150mV &plusmn; 10% of output voltage on a 32 Ohm
4643speaker impedance.</li>
4644 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4645</ul>
4646
4647<h3 id="7_8_3_near_ultrasound">7.8.3. Near-Ultrasound </h3>
4648
4649<p>Near-Ultrasound audio is the 18.5 kHz to 20 kHz band.
4650Device implementations MUST correctly report the support
4651of near-ultrasound audio capability via the
4652<a href="http://developer.android.com/reference/android/media/AudioManager.html#getProperty(java.lang.String)">AudioManager.getProperty</a>
4653API as follows:
4654</p>
4655
4656<ul>
4657 <li>If
4658 <a href="http://developer.android.com/reference/android/media/AudioManager.html#PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND">PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND</a>
4659 is "true", then
4660 <ul>
4661 <li>The microphone's mean power response in the 18.5 kHz to 20 kHz band MUST be no more than
4662 15 dB below the response at 2 kHz.</li>
4663 <li>The signal to noise ratio of the microphone MUST be no lower than 80 dB.</li>
4664 </ul>
4665 </li>
4666 <li>If
4667 <a href="http://developer.android.com/reference/android/media/AudioManager.html#PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND">PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND</a>
4668 is "true", then the speaker's mean response in 18.5 kHz - 20 kHz MUST be no lower than 40 dB
4669 below the response at 2 kHz.
4670 </li>
4671</ul>
4672
4673<h1 id="8_performance_power">8. Performance and Power</h1>
4674
4675
4676<p>Some minimum performance and power criteria are critical to the user experience
4677and impact the baseline assumptions developers would have when developing an app.
4678Android Watch devices SHOULD and other type of device implementations MUST meet
4679the following criteria:</p>
4680
4681<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4682
4683
4684<p>Device implementations MUST provide a smooth user interface by ensuring a
4685consistent frame rate and response times for applications and games. Device
4686implementations MUST meet the following requirements: </p>
4687
4688<ul>
4689 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4690often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4691 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4692list of 10K list entries as defined by the Android Compatibility Test Suite
4693(CTS) in less than 36 secs.</li>
4694 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4695application after it has been launched MUST take less than 1 second.</li>
4696</ul>
4697
4698<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4699
4700
4701<p>Device implementations MUST ensure internal storage file access performance consistency for read
4702and write operations. </p>
4703
4704<ul>
4705 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4706for a 256MB file using 10MB write buffer.</li>
4707 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4708256MB file using 4KB write buffer.</li>
4709 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4710a 256MB file using 10MB write buffer.</li>
4711 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4712256MB file using 4KB write buffer.</li>
4713</ul>
4714
4715<h2 id="8_3_power_saving_modes">8.3. Power-Saving Modes</h2>
4716
4717<p>All apps exempted from App Standby and/or Doze mode MUST be made visible to
4718the end user. Further, the triggering, maintenance, wakeup algorithms and
4719the use of Global system settings of these power-saving modes MUST not deviate
4720from the Android Open Source Project.</p>
4721
4722<h2 id="8_4_power_consumption_accounting">8.4. Power Consumption Accounting</h2>
4723
4724<p>A more accurate accounting and reporting of the power consumption provides the
4725app developer both the incentives and the tools to optimize the power usage pattern
4726of the application. Therefore, device implementations:</p>
4727
4728<ul>
4729 <li>MUST be able to track hardware component power usage and attribute that power
4730 usage to specific applications. Specifically, implementations:
4731 <ul>
4732 <li>MUST provide a per-component power profile that defines the current consumption
4733 value for each hardware component and the approximate battery drain caused by the
4734 components over time as documented in the Android Open Source Project site [<a
4735href="http://source.android.com/devices/tech/power/values.html">Resources, 123</a>].</li>
4736 <li>MUST report all power consumption values in milliampere hours (mAh)</li>
4737 <li>SHOULD be attributed to the hardware component itself if unable to
4738 attribute hardware component power usage to an application.</li>
4739 <li>MUST report CPU power consumption per each process's UID. The Android Open
4740 Source Project meets the requirement through the <code>uid_cputime</code>
4741 kernel module implementation.</li>
4742 </ul>
4743 </li>
4744 <li>MUST make this power usage available via the <code>adb shell dumpsys
4745 batterystats</code> shell command to the app developer [<a
4746href="http://source.android.com/devices/tech/power/batterystats.html">Resources, 124</a>].</li>
4747 <li>MUST honor the android.intent.action.POWER_USAGE_SUMMARY intent and display
4748 a settings menu that shows this power usage [<a
4749href="http://developer.android.com/reference/android/content/Intent.html#ACTION_POWER_USAGE_SUMMARY">Resources,
4750125</a>].</li>
4751</ul>
4752
4753<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4754
4755
4756<p>Device implementations MUST implement a security model consistent with the
4757Android platform security model as defined in Security and Permissions
4758reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 126</a>] in the Android developer documentation. Device implementations MUST support
4759installation of self-signed applications without requiring any additional
4760permissions/certificates from any third parties/authorities. Specifically,
4761compatible devices MUST support the security mechanisms described in the follow
4762subsections.</p>
4763
4764<h2 id="9_1_permissions">9.1. Permissions</h2>
4765
4766
4767<p>Device implementations MUST support the Android permissions model as defined in
4768the Android developer documentation [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 126</a>]. Specifically, implementations MUST enforce each permission defined as
4769described in the SDK documentation; no permissions may be omitted, altered, or
4770ignored. Implementations MAY add additional permissions, provided the new
4771permission ID strings are not in the android.* namespace.</p>
4772
4773<p>Permissions with a protection level of dangerous are runtime permissions. Applications
4774with targetSdkVersion > 22 request them at runtime. Device implementations:</p>
4775
4776<ul>
4777<li>MUST show a dedicated interface for the user to decide whether to grant the
4778requested runtime permissions and also provide an interface for the user to manage
4779runtime permissions.</li>
4780<li>MUST have one and only one implementation of both user interfaces.</li>
4781<li>MUST NOT grant any runtime permissions to preinstalled apps unless:
4782 <ul>
4783 <li>the user's consent can be obtained before the application uses it</li>
4784 <li>the runtime permissions are associated with an intent pattern for which the preinstalled
4785 application is set as the default handler</li>
4786 </ul>
4787</li>
4788</ul>
4789
4790<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4791
4792
4793<p>Device implementations MUST support the Android application sandbox model, in
4794which each application runs as a unique Unixstyle UID and in a separate
4795process. Device implementations MUST support running multiple applications as
4796the same Linux user ID, provided that the applications are properly signed and
4797constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 126</a>].</p>
4798
4799<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4800
4801
4802<p>Device implementations MUST support the Android file access permissions model
4803as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 126</a>].</p>
4804
4805<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4806
4807
4808<p>Device implementations MAY include runtime environments that execute
4809applications using some other software or technology than the Dalvik Executable
4810Format or native code. However, such alternate execution environments MUST NOT
4811compromise the Android security model or the security of installed Android
4812applications, as described in this section.</p>
4813
4814<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4815standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4816
4817<p>Alternate runtimes MUST NOT be granted access to resources protected by
4818permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
4819&lt;uses-permission&gt; mechanism.</p>
4820
4821<p>Alternate runtimes MUST NOT permit applications to make use of features
4822protected by Android permissions restricted to system applications.</p>
4823
4824<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4825alternate runtimes:</p>
4826
4827<ul>
4828 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4829Linux user IDs, etc.).</li>
4830 <li>MAY provide a single Android sandbox shared by all applications using the
4831alternate runtime.</li>
4832 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4833sandbox of any other app installed on the device, except through the standard
4834Android mechanisms of shared user ID and signing certificate.</li>
4835 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4836corresponding to other Android applications.</li>
4837 <li>MUST NOT be launched with, be granted, or grant to other applications any
4838privileges of the superuser (root), or of any other user ID.</li>
4839</ul>
4840
4841<p>The .apk files of alternate runtimes MAY be included in the system image of a
4842device implementation, but MUST be signed with a key distinct from the key used
4843to sign other applications included with the device implementation.</p>
4844
4845<p>When installing applications, alternate runtimes MUST obtain user consent for
4846the Android permissions used by the application. If an application needs to
4847make use of a device resource for which there is a corresponding Android
4848permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4849user that the application will be able to access that resource. If the runtime
4850environment does not record application capabilities in this manner, the
4851runtime environment MUST list all permissions held by the runtime itself when
4852installing any application using that runtime.</p>
4853
4854<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4855
4856<div class="note">
4857<p>This feature is optional for all device types.</p>
4858</div>
4859
4860
4861<p>Android includes support for multiple users and provides support for full user
4862isolation [<a href="http://developer.android.com/reference/android/os/UserManager.html">Resources, 127</a>]. Device implementations MAY enable multiple users, but when enabled MUST meet
4863the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/traditional.html">Resources, 128</a>]:</p>
4864
4865<ul>
4866 <li>Device implementations that do not declare the android.hardware.telephony
4867feature flag MUST support restricted profiles, a feature that allows device
4868owners to manage additional users and their capabilities on the device. With
4869restricted profiles, device owners can quickly set up separate environments for
4870additional users to work in, with the ability to manage finer-grained
4871restrictions in the apps that are available in those environments.</li>
4872 <li>Conversely device implementations that declare the android.hardware.telephony
4873feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4874implementation of controls to enable /disable other users from accessing the
4875voice calls and SMS.</li>
4876 <li>Device implementations MUST, for each user, implement a security model
4877consistent with the Android platform security model as defined in Security and
4878Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 126</a>].</li>
4879 <li>Each user instance on an Android device MUST have separate and isolated
4880external storage directories. Device implementations MAY store multiple users'
4881data on the same volume or filesystem. However, the device implementation MUST
4882ensure that applications owned by and running on behalf a given user cannot
4883list, read, or write to data owned by any other user. Note that removable
4884media, such as SD card slots, can allow one user to access another&rsquo;s data by
4885means of a host PC. For this reason, device implementations that use removable
4886media for the external storage APIs MUST encrypt the contents of the SD card if
4887multiuser is enabled using a key stored only on non-removable media accessible
4888only to the system. As this will make the media unreadable by a host PC, device
4889implementations will be required to switch to MTP or a similar system to
4890provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4891implementations MAY but SHOULD NOT enable multi-user if they use removable
4892media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 129</a>] for primary external storage.</li>
4893</ul>
4894
4895<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4896
4897
4898<p>Android includes support for warning users of any outgoing premium SMS message
4899[<a href="http://en.wikipedia.org/wiki/Short_code">Resources, 130</a>]. Premium SMS messages are text messages sent to a service registered with a
4900carrier that may incur a charge to the user. Device implementations that
4901declare support for android.hardware.telephony MUST warn users before sending a
4902SMS message to numbers identified by regular expressions defined in
4903/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4904Project provides an implementation that satisfies this requirement.</p>
4905
4906<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4907
4908
4909<p>The Android Sandbox includes features that use the Security-Enhanced Linux
4910(SELinux) mandatory access control (MAC) system and other security features in
4911the Linux kernel. SELinux or any other security features implemented below
4912the Android framework:</p>
4913
4914<ul>
4915 <li>MUST maintain compatibility with existing applications.</li>
4916 <li>MUST NOT have a visible user interface when a security violation is detected
4917and successfully blocked, but MAY have a visible user interface when an
4918unblocked security violation occurs resulting in a successful exploit.</li>
4919 <li>SHOULD NOT be user or developer configurable.</li>
4920</ul>
4921
4922<p>If any API for configuration of policy is exposed to an application that can
4923affect another application (such as a Device Administration API), the API MUST
4924NOT allow configurations that break compatibility.</p>
4925
4926<p>Devices MUST implement SELinux or, if using a kernel other than Linux, an
4927equivalent mandatory access control system. Devices MUST also meet the
4928following requirements, which are satisfied by the reference implementation
4929in the upstream Android Open Source Project.</p>
4930
4931<p>Device implementations:</p>
4932
4933<ul>
4934 <li>MUST set SELinux to global enforcing mode.</li>
4935 <li>MUST configure all domains in enforcing mode. No permissive mode domains
4936are allowed, including domains specific to a device/vendor.</li>
4937 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4938external/sepolicy folder provided in the upstream Android Open Source Project (AOSP) and
4939the policy MUST compile with all neverallow rules present, for both AOSP SELinux
4940domains as well as device/vendor specific domains.</li>
4941</ul>
4942
4943<p>Device implementations SHOULD retain the default SELinux policy provided in the
4944external/sepolicy folder of the upstream Android Open Source Project and only
4945further add to this policy for their own device-specific configuration. Device
4946implementations MUST be compatible with the upstream Android Open Source Project.
4947</p>
4948
4949<h2 id="9_8_privacy">9.8. Privacy</h2>
4950
4951<p>If the device implements functionality in the system that captures the contents
4952displayed on the screen and/or records the audio stream played on the device,
4953it MUST continuously notify the user whenever this functionality is enabled and
4954actively capturing/recording.</p>
4955
4956<p>If a device implementation has a mechanism that routes network data traffic
4957through a proxy server or VPN gateway by default (for example, preloading a VPN
4958service with android.permission.CONTROL_VPN granted), the device implementation
4959MUST ask for the user's consent before enabling that mechanism.</p>
4960
4961<p>If a device implementation has a USB port with USB peripheral mode support,
4962it MUST present a user interface asking for the user's consent before allowing
4963access to the contents of the shared storage over the USB port.</p>
4964
4965<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4966
4967<div class="note">
4968<p>Optional for Android device implementations without a lock screen.</p>
4969</div>
4970
4971<p>If the device implementation supports a secure lock screen reporting "<code>true</code>"
4972for KeyguardManager.isDeviceSecure()
4973[<a href="http://developer.android.com/reference/android/app/KeyguardManager.html#isDeviceSecure()">Resources, 131</a>],
4974and is not a device with restricted memory as reported through the
4975ActivityManager.isLowRamDevice() method, then the device MUST support full-disk encryption
4976[<a href="http://source.android.com/devices/tech/security/encryption/index.html">Resources, 132</a>]
4977of the application private data (/data partition), as well as the application
4978shared storage partition (/sdcard partition) if it is a permanent, non-removable
4979part of the device.</p>
4980
4981<p>For device implementations supporting full-disk encryption and with Advanced
4982Encryption Standard (AES) crypto performance above 50MiB/sec, the full-disk
4983encryption MUST be enabled by default at the time the user has completed the out-of-box
4984setup experience. If a device implementation is already launched on an earlier Android
4985version with full-disk encryption disabled by default, such a device cannot
4986meet the requirement through a system software update and thus MAY be exempted.</p>
4987
4988<p>Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4989for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4990be written to storage at any time without being encrypted. Other than when in
4991active use, the encryption key SHOULD be AES encrypted with the lockscreen
4992passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4993If the user has not specified a lockscreen passcode or has disabled use of the
4994passcode for encryption, the system SHOULD use a default passcode to wrap the
4995encryption key. If the device provides a hardware-backed keystore, the password
4996stretching algorithm MUST be cryptographically bound to that keystore. The
4997encryption key MUST NOT be sent off the device (even when wrapped with the user
4998passcode and/or hardware bound key). The upstream Android Open Source project
4999provides a preferred implementation of this feature based on the Linux kernel
5000feature dm-crypt.</p>
5001
5002<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
5003
5004<p>
5005Verified boot is a feature that guarantees the integrity of the device software.
5006If a device implementation supports the feature, it MUST:
5007</p>
5008<ul>
5009<li>Declare the platform feature flag android.software.verified_boot</li>
5010<li>Perform verification on every boot sequence</li>
5011<li>Start verification from an immutable hardware key that is the root of trust,
5012and go all the way up to the system partition</li>
5013<li>Implement each stage of verification to check the integrity and authenticity
5014of all the bytes in the next stage before executing the code in the next stage</li>
5015<li>Use verification algorithms as strong as current recommendations
5016from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
5017</ul>
5018
5019<p>The upstream Android Open Source Project provides a preferred implementation of this
5020feature based on the Linux kernel feature dm-verity.</p>
5021
5022<p>Starting from Android 6.0, device implementations with Advanced Encryption Standard (AES)
5023crypto perfomance above 50MiB/seconds MUST support verified boot for device integrity.
5024If a device implementation is already launched without supporting verified boot on an earlier
5025version of Android, such a device can not add support for this feature with a system software
5026update and thus are exempted from the requirement.</p>
5027
5028<h2 id="9_11_keys_and_credentials">9.11. Keys and Credentials</h2>
5029
5030<p>The Android Keystore System
5031[<a href="https://developer.android.com/training/articles/keystore.html">Resources, 133</a>]
5032allows app developers to store cryptographic keys in a container and use them in cryptographic
5033operations through the KeyChain API
5034[<a href="https://developer.android.com/reference/android/security/KeyChain.html">Resources, 134</a>]
5035or the Keystore API
5036 [<a href="https://developer.android.com/reference/java/security/KeyStore.html">Resources, 135</a>].
5037</p>
5038
5039<p>All Android device implementations MUST meet the following requirements:</p>
5040
5041<ul>
5042<li>SHOULD not limit the number of keys that can be generated, and MUST at least allow more
5043than 8,192 keys to be imported.</li>
5044<li>The lock screen authentication MUST rate limit attempts and SHOULD have an exponential
5045 backoff algorithm as implemented in the Android Open Source Project.</li>
5046<li>When the device implementation supports a secure lock screen and has a secure hardware
5047 such as a Secure Element (SE) where a Trusted Execution Environment (TEE) can be implemented,
5048 then it:
5049 <ul>
5050 <li>Is STRONGLY RECOMMENDED to back up the keystore implementation with the secure hardware.
5051 The upstream Android Open Source Project provides the Keymaster Hardware Abstraction Layer
5052 (HAL) implementation that can be used to satisfy this requirement.</li>
5053 <li>MUST perform the lock screen authentication in the secure hardware if the device has a
5054 hardware-backed keystore implementation and only when successful allow the authentication-bound
5055 keys to be used. The upstream Android Open Source Project provides the Gatekeeper Hardware
5056 Abstraction Layer (HAL) that can be used to satisfy this requirement
5057 [<a href="http://source.android.com/devices/tech/security/authentication/gatekeeper.html">Resources, 136</a>].</li>
5058 </ul>
5059</li>
5060</ul>
5061
5062<p>Note that while the above TEE-related requirements are stated as STRONGLY RECOMMENDED, the
5063 Compatibility Definition for the next API version is planned to changed these to REQIUIRED. If a
5064 device implementation is already launched on an earlier Android version and has not implemented a
5065 trusted operating system on the secure hardware, such a device might not be able to meet the
5066 requirements through a system software update and thus is STRONGLY RECOMMENDED to implement a
5067 TEE.</p>
5068
5069<h2 id="9_12_data_deletion">9.12. Data Deletion</h2>
5070
5071<p>Devices MUST provide users with a mechanism to perform a "Factory Data Reset"
5072that allows logical and physical deletion of all data. This MUST satisfy relevant
5073industry standards for data deletion such as NIST SP800-88. This MUST be used for
5074the implementation of the wipeData() API (part of the Android Device Administration API)
5075described in <a href="#3_9_device_administration">section 3.9 Device Administration</a>.</p>
5076
5077<p>Devices MAY provide a fast data wipe that conducts a logical data erase.</p>
5078
5079<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
5080
5081
5082<p>Device implementations MUST pass all tests described in this section.</p>
5083
5084<p>However, note that no software test package is fully comprehensive. For this
5085reason, device implementers are <strong>STRONGLY RECOMMENDED</strong> to make the minimum number of changes as possible to the reference and
5086preferred implementation of Android available from the Android Open Source
5087Project. This will minimize the risk of introducing bugs that create
5088incompatibilities requiring rework and potential device updates.</p>
5089
5090<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
5091
5092
5093<p>Device implementations MUST pass the Android Compatibility Test Suite (CTS) [<a href="http://source.android.com/compatibility/index.html">Resources, 137</a>] available from the Android Open Source Project, using the final shipping
5094software on the device. Additionally, device implementers SHOULD use the
5095reference implementation in the Android Open Source tree as much as possible,
5096and MUST ensure compatibility in cases of ambiguity in CTS and for any
5097reimplementations of parts of the reference source code.</p>
5098
5099<p>The CTS is designed to be run on an actual device. Like any software, the CTS
5100may itself contain bugs. The CTS will be versioned independently of this
5101Compatibility Definition, and multiple revisions of the CTS may be released for
5102Android 6.0. Device implementations MUST pass the latest CTS version available
5103at the time the device software is completed.</p>
5104
5105<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
5106
5107
5108<p>Device implementations MUST correctly execute all applicable cases in the CTS
5109Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
5110is intended to be run by a human operator to test functionality that cannot be
5111tested by an automated system, such as correct functioning of a camera and
5112sensors.</p>
5113
5114<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
5115that is optional. Device implementations MUST pass all tests for hardware that
5116they possess; for instance, if a device possesses an accelerometer, it MUST
5117correctly execute the Accelerometer test case in the CTS Verifier. Test cases
5118for features noted as optional by this Compatibility Definition Document MAY be
5119skipped or omitted.</p>
5120
5121<p>Every device and every build MUST correctly run the CTS Verifier, as noted
5122above. However, since many builds are very similar, device implementers are not
5123expected to explicitly run the CTS Verifier on builds that differ only in
5124trivial ways. Specifically, device implementations that differ from an
5125implementation that has passed the CTS Verifier only by the set of included
5126locales, branding, etc. MAY omit the CTS Verifier test.</p>
5127
5128<h1 id="11_updatable_software">11. Updatable Software</h1>
5129
5130
5131<p>Device implementations MUST include a mechanism to replace the entirety of the
5132system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
5133device restart MAY be required.</p>
5134
5135<p>Any method can be used, provided that it can replace the entirety of the
5136software preinstalled on the device. For instance, any of the following
5137approaches will satisfy this requirement:</p>
5138
5139<ul>
5140 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
5141 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
5142 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
5143</ul>
5144
5145<p>However, if the device implementation includes support for an unmetered data
5146connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
5147
5148<ul>
5149<li>Android Automotive implementations SHOULD support OTA downloads with offline
5150update via reboot.</li>
5151<li>All other device implementations MUST support OTA downloads with offline
5152update via reboot.</li>
5153</ul>
5154
5155<p>The update mechanism used MUST support updates without wiping user data. That
5156is, the update mechanism MUST preserve application private data and application
5157shared data. Note that the upstream Android software includes an update
5158mechanism that satisfies this requirement.</p>
5159
5160<p>For device implementations that are launching with Android 6.0 and later, the
5161update mechanism SHOULD support verifying that the system image is binary
5162identical to expected result following an OTA. The block-based OTA
5163implementation in the upstream Android Open Source Project, added since Android
51645.1, satisfies this requirement.</p>
5165
5166<p>If an error is found in a device implementation after it has been released but
5167within its reasonable product lifetime that is determined in consultation with
5168the Android Compatibility Team to affect the compatibility of third-party
5169applications, the device implementer MUST correct the error via a software
5170update available that can be applied per the mechanism just described.</p>
5171
5172<p>Android includes features that allow the Device Owner app (if present) to control the
5173installation of system updates. To facilitate this, the system update subsystem
5174for devices that report android.software.device_admin MUST implement the behavior
5175described in the SystemUpdatePolicy class
5176[<a href="http://developer.android.com/reference/android/app/admin/SystemUpdatePolicy.html">
5177Resources, 138</a>].</p>
5178
5179<h1 id="12_document_changelog">12. Document Changelog</h1>
5180
5181<p>The following table contains a summary of the changes to the Compatibility
5182Definition in this release.</p>
5183<table>
5184 <tr>
5185 <th>Section</th>
5186 <th>Summary of changes</th>
5187 </tr>
5188 <tr>
5189 <td>Various</td>
5190 <td>Replaced instances of the "encouraged" term with "RECOMMENDED"</td>
5191 </tr>
5192 <tr>
5193 <td>2. Device Types</td>
5194 <td>Update for Android Automotive implementations</td>
5195 </tr>
5196 <tr>
5197 <td>3.2.2. Build Parameters</td>
5198 <td>Additions for the hardware serial number and for the security patch level of a build</td>
5199 </tr>
5200 <tr>
5201 <td>3.2.3.2. Intent Resolution</td>
5202 <td>Section renamed from "Intent Overrides" to "Intent Resolution," with new requirements related to authoritative default app linking</td>
5203 </tr>
5204 <tr>
5205 <td>3.3.1. Application Binary Interfaces</td>
5206 <td>Additions for Android ABI support; change related to Vulkan library name</td>
5207 </tr>
5208 <tr>
5209 <td>3.4.1. WebView Compatibility</td>
5210 <td>Change for the user agent string reported by the WebView</td>
5211 </tr>
5212 <tr>
5213 <td>3.7. Runtime Compatibility</td>
5214 <td>Updates to memory allocation table</td>
5215 </tr>
5216 <tr>
5217 <td>3.8.4. Search</td>
5218 <td>Updates regarding Assistant requirements</td>
5219 </tr>
5220 <tr>
5221 <td>3.8.6. Themes</td>
5222 <td>Added requirement to support black system icons when requested by the SYSTEM_UI_FLAG_LIGHT_STATUS_BAR flag</td>
5223 </tr>
5224 <tr>
5225 <td>3.9.1. Device Provisioning</td>
5226 <td>Contains new sections for device owner provisioning and managed profile provisioning</td>
5227 </tr>
5228 <tr>
5229 <td>3.9.2. Managed Profile Support</td>
5230 <td>New section with requirements for device support of managed profile functionality</td>
5231 </tr>
5232<tr>
5233 <td>3.12.1. TV App</td>
5234 <td>Added section to clarify TV App requirements for Android Television devices</td>
5235 </tr>
5236 <tr>
5237 <td>3.12.1.1. Electronic Program Guide</td>
5238 <td>Added section to clarify EPG requirements for Android Television devices</td>
5239 </tr>
5240 <tr>
5241 <td>3.12.1.2. Navigation</td>
5242 <td>Added section to clarify TV App navigation requirements for Android Television devices</td>
5243 </tr>
5244 <td>3.12.1.3. TV input app linking</td>
5245 <td>Added section to clarify TV input app linking support requirements for Android Television devices</td>
5246 </tr>
5247 <tr>
5248 <td>5.1. Media Codecs</td>
5249 <td>Updates regarding support for core media formats and decoding.</td>
5250 </tr>
5251 <tr>
5252 <td>5.1.3. Video Codecs</td>
5253 <td>Changes and additions related to Android Televisions</td>
5254 </tr>
5255 <tr>
5256 <td>5.2. Video Encoding</td>
5257 <td>Changes for encoders</td>
5258 </tr>
5259 <tr>
5260 <td>5.3. Video Decoding</td>
5261 <td>Changes for decoders, including regarding support for dynamic video resolution, frame rate
5262switching, and more</td>
5263 </tr>
5264 <tr>
5265 <td>5.4. Audio Recording</td>
5266 <td>Additions related to audio capture</td>
5267 </tr>
5268 <tr>
5269 <td>5.6. Audio Latency</td>
5270 <td>Update regarding reporting of support for low-latency audio</td>
5271 </tr>
5272 <tr>
5273 <td>5.10. Professional Audio</td>
5274 <td>General updates for professional audio support; updates for mobile device (jack) specifications, USB audio host mode, and other updates</td>
5275 </tr>
5276 <tr>
5277 <td>5.9. Musical Instrument Digital Interface (MIDI)</td>
5278 <td>Added new section on optional Musical Instrument Digital Interface (MIDI) support</td>
5279 </tr>
5280<tr>
5281 <td>6.1. Developer Tools</td>
5282 <td>Update for drivers supporting Windows 10</td>
5283 </tr>
5284 <tr>
5285 <td>7.1.1.3. Screen Density</td>
5286 <td>Updates for screen density, for example related to an Android watch</td>
5287 </tr>
5288 <tr>
5289 <td>7.2.3. Navigation Keys</td>
5290 <td>Updated requirements for device implementations that include the Assist action</td>
5291 </tr>
5292 <tr>
5293 <td>7.3. Sensors (and subsections)</td>
5294 <td>New requirements for some sensor types</td>
5295 </tr>
5296 <tr>
5297 <td>7.3.9. High Fidelity Sensors</td>
5298 <td>New section with requirements for devices supporting high fidelity sensors</td>
5299 </tr>
5300 <tr>
5301 <td>7.3.10. Fingerprint Sensor</td>
5302 <td>New section on requirements related to fingerprint sensors</td>
5303 </tr>
5304 <tr>
5305 <td>7.4.2. IEEE 802.11 (Wi-Fi)</td>
5306 <td>Updates regarding support for multicast DNS (mDNS)</td>
5307 </tr>
5308 <tr>
5309 <td>7.4.3. Bluetooth</td>
5310 <td>Addition related to Resolvable Private Address (RPA) for Bluetooth Low Energy (BLE)</td>
5311 </tr>
5312 <tr>
5313 <td>7.4.4. Near-Field Communications</td>
5314 <td>Additions to requirements for Near-Field Communications (NFC)</td>
5315 </tr>
5316 <tr>
5317 <td>7.4.5. Minimum Network Capability</td>
5318 <td>Added requirements for IPv6 support</td>
5319 </tr>
5320 <tr>
5321 <td>7.6.3. Adoptable Storage</td>
5322 <td>New section for implementation of adoptable storage</td>
5323 </tr>
5324 <tr>
5325 <td>7.7. USB</td>
5326 <td>Requirement related to implementing the AOA specification</td>
5327 </tr>
5328 <tr>
5329 <td>7.8.3. Near-Ultrasound</td>
5330 <td>Additions related to near-ultrasound recording, playback, and audio</td>
5331 </tr>
5332 <tr>
5333 <td>8.3. Power-Saving Modes</td>
5334 <td>New section with requirements regarding the App Standby and Doze modes</td>
5335 </tr>
5336<tr>
5337 <td>8.4. Power Consumption Accounting</td>
5338 <td>New section with requirements for tracking hardware component power usage and attributing that power usage to specific applications</td>
5339 </tr>
5340 <tr>
5341 <td>9.1. Permissions</td>
5342 <td>Addition to Permissions requirements</td>
5343 </tr>
5344<tr>
5345 <td>9.7. Kernel Security Features</td>
5346 <td>SE Linux updates</td>
5347 </tr>
5348<tr>
5349 <td>9.8. Privacy</td>
5350 <td>Addition regarding user's consent for access to shared storage over a USB port</td>
5351 </tr>
5352 <tr>
5353 <td>9.9. Full-Disk Encryption</td>
5354 <td>Requirements related to full disk encryption</td>
5355 </tr>
5356 <tr>
5357 <td>9.10. Verified Boot</td>
5358 <td>Additional requirement for verified boot</td>
5359 </tr>
5360 <tr>
5361 <td>9.11. Keys and Credentials</td>
5362 <td>New section of requirements related to keys and credentials</td>
5363 </tr>
5364 <tr>
5365 <td>9.12. Data Deletion</td>
5366 <td>New section for "Factory Data Reset"</td>
5367 </tr>
5368 <tr>
5369 <td>11. Updatable Software</td>
5370 <td>Requirement related to the system update policy set by the device owner</td>
5371 </tr>
5372 </table>
5373
5374
5375<h1 id="13_contact_us">13. Contact Us</h1>
5376
5377
5378<p>You can join the android-compatibility forum <a href="https://groups.google.com/forum/#!forum/android-compatibility">[Resources, 139</a>] and ask for clarifications or bring up any issues that you think the document
5379does not cover.</p>
5380
5381<h1 id="14_resources">14. Resources</h1>
5382
5383<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
5384
5385<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
5386
5387<p>3. Android Television features: <a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK</a></p>
5388
5389<p>4. Android Watch feature: <a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_WATCH">http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_WATCH</a></p>
5390
5391<p>5. Android UI_MODE_TYPE_CAR API: <a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR</a></p>
5392
5393<p>6. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
5394
5395<p>7. Android Permissions reference: <a href="http://developer.android.com/reference/android/Manifest.permission.html">http://developer.android.com/reference/android/Manifest.permission.html</a></p>
5396
5397<p>8. android.os.Build reference: <a href="http://developer.android.com/reference/android/os/Build.html">http://developer.android.com/reference/android/os/Build.html</a></p>
5398
5399<p>9. Android 6.0 allowed version strings: <a href="http://source.android.com/compatibility/6.0/versions.html">http://source.android.com/compatibility/6.0/versions.html</a></p>
5400
5401<p>10. Android Developer Settings: <a href="http://developer.android.com/reference/android/provider/Settings.html">http://developer.android.com/reference/android/provider/Settings.html</a></p>
5402
5403<p>11. Telephony Provider: <a href="http://developer.android.com/reference/android/provider/Telephony.html">http://developer.android.com/reference/android/provider/Telephony.html</a></p>
5404
5405<p>12. Android NDK ABI Management: <a href="https://developer.android.com/ndk/guides/abis.html">https://developer.android.com/ndk/guides/abis.html</a></p>
5406
5407<p>13. Advanced SIMD architecture: <a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html</a></p>
5408
5409<p>14. Android Extension Pack: <a href="http://developer.android.com/guide/topics/graphics/opengl.html#aep">http://developer.android.com/guide/topics/graphics/opengl.html#aep</a></p>
5410
5411<p>15. android.webkit.WebView class: <a href="http://developer.android.com/reference/android/webkit/WebView.html">http://developer.android.com/reference/android/webkit/WebView.html</a></p>
5412
5413<p>16. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
5414
5415<p>17. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
5416
5417<p>18. HTML5 offline capabilities:<a href="http://dev.w3.org/html5/spec/Overview.html#offline"> http://dev.w3.org/html5/spec/Overview.html#offline</a></p>
5418
5419<p>19. HTML5 video tag: <a href="http://dev.w3.org/html5/spec/Overview.html#video">http://dev.w3.org/html5/spec/Overview.html#video</a></p>
5420
5421<p>20. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
5422
5423<p>21. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
5424
5425<p>22. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
5426
5427<p>23. Dalvik Executable Format and bytecode specification: available in the
5428Android source code, at dalvik/docs</p>
5429
5430<p>24. AppWidgets: <a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">http://developer.android.com/guide/practices/ui_guidelines/widget_design.html</a></p>
5431
5432<p>25. Notifications: <a href="http://developer.android.com/guide/topics/ui/notifiers/notifications.html">http://developer.android.com/guide/topics/ui/notifiers/notifications.html</a></p>
5433
5434<p>26. Application Resources: <a href="https://developer.android.com/guide/topics/resources/available-resources.html">https://developer.android.com/guide/topics/resources/available-resources.html</a></p>
5435
5436<p>27. Status Bar icon style guide: <a href="http://developer.android.com/design/style/iconography.html">http://developer.android.com/design/style/iconography.html</a></p>
5437
5438<p>28. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a></p>
5439
5440<p>29. Search Manager: <a href="http://developer.android.com/reference/android/app/SearchManager.html">http://developer.android.com/reference/android/app/SearchManager.html</a></p>
5441
5442<p>30. Action Assist: <a href="http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST">http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST</a></p>
5443
5444<p>31. Android Assist APIs: <a href="https://developer.android.com/reference/android/app/assist/package-summary.html">https://developer.android.com/reference/android/app/assist/package-summary.html</a></p>
5445
5446<p>32. Toasts: <a href="http://developer.android.com/reference/android/widget/Toast.html">http://developer.android.com/reference/android/widget/Toast.html</a></p>
5447
5448<p>33. Themes: <a href="http://developer.android.com/guide/topics/ui/themes.html">http://developer.android.com/guide/topics/ui/themes.html</a></p>
5449
5450<p>34. R.style class: <a href="http://developer.android.com/reference/android/R.style.html">http://developer.android.com/reference/android/R.style.html</a></p>
5451
5452<p>35. Material design: <a href="http://developer.android.com/reference/android/R.style.html#Theme_Material">http://developer.android.com/reference/android/R.style.html#Theme_Material</a></p>
5453
5454<p>36. Live Wallpapers: <a href="http://developer.android.com/reference/android/service/wallpaper/WallpaperService.html">http://developer.android.com/reference/android/service/wallpaper/WallpaperService.html</a></p>
5455
5456<p>37. Overview screen resources: <a href="http://developer.android.com/guide/components/recents.html">http://developer.android.com/guide/components/recents.html</a></p>
5457
5458<p>38. Screen pinning: <a href="https://developer.android.com/about/versions/android-5.0.html#ScreenPinning">https://developer.android.com/about/versions/android-5.0.html#ScreenPinning</a></p>
5459
5460<p>39. Input methods: <a href="http://developer.android.com/guide/topics/text/creating-input-method.html">http://developer.android.com/guide/topics/text/creating-input-method.html</a></p>
5461
5462<p>40. Media Notification: <a href="https://developer.android.com/reference/android/app/Notification.MediaStyle.html">https://developer.android.com/reference/android/app/Notification.MediaStyle.html</a></p>
5463
5464<p>41. Dreams: <a href="http://developer.android.com/reference/android/service/dreams/DreamService.html">http://developer.android.com/reference/android/service/dreams/DreamService.html</a></p>
5465
5466<p>42. Settings.Secure LOCATION_MODE: <a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE</a></p>
5467
5468<p>43. Unicode 6.1.0: <a href="http://www.unicode.org/versions/Unicode6.1.0/">http://www.unicode.org/versions/Unicode6.1.0/</a></p>
5469
5470<p>44. Android Device Administration: <a href="http://developer.android.com/guide/topics/admin/device-admin.html">http://developer.android.com/guide/topics/admin/device-admin.html</a></p>
5471
5472<p>45. DevicePolicyManager reference: <a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html</a></p>
5473
5474<p>46. Device Owner App: <a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)</a></p>
5475
5476
5477<p>47. Android Device Owner Provisioning Flow: <a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_DEVICE">http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_DEVICE</a></p>
5478
5479<p>48. Device Owner Provisioning via NFC: <a href="https://source.android.com/devices/tech/admin/provision.html#device_owner_provisioning_via_nfc">https://source.android.com/devices/tech/admin/provision.html#device_owner_provisioning_via_nfc</a></p>
5480
5481<p>49. Android Profile Owner App:<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isProfileOwnerApp(java.lang.String)">http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isProfileOwnerApp(java.lang.String)</a></p>
5482
5483<p>50. Android Managed Profile Provisioning flow: <a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE">http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE</a></p>
5484
5485<p>51. Android Accessibility Service APIs: <a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html</a></p>
5486
5487<p>52. Android Accessibility APIs: <a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">http://developer.android.com/reference/android/view/accessibility/package-summary.html</a></p>
5488
5489<p>53. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
5490
5491<p>54. Text-To-Speech APIs: <a href="http://developer.android.com/reference/android/speech/tts/package-summary.html">http://developer.android.com/reference/android/speech/tts/package-summary.html</a></p>
5492
5493<p>55. Television Input Framework: <a href="https://source.android.com/devices/tv/index.html">https://source.android.com/devices/tv/index.html</a></p>
5494
5495<p>56. TV App channels: <a href="http://developer.android.com/reference/android/media/tv/TvContract.Channels.html">http://developer.android.com/reference/android/media/tv/TvContract.Channels.html</a></p>
5496
5497<p>57. Third-party TV inputs: <a href="https://source.android.com/devices/tv/index.html#third-party_input_example">https://source.android.com/devices/tv/index.html#third-party_input_example</a></p>
5498
5499<p>58. TV inputs: <a href="https://source.android.com/devices/tv/index.html#tv_inputs">https://source.android.com/devices/tv/index.html#tv_inputs</a></p>
5500
5501<p>59. TV channel EPG fields: <a href="https://developer.android.com/reference/android/media/tv/TvContract.Programs.html">https://developer.android.com/reference/android/media/tv/TvContract.Programs.html</a></p>
5502
5503<p>60. TV input app linking: <a href="http://developer.android.com/reference/android/media/tv/TvContract.Channels.html#COLUMN_APP_LINK_INTENT_URI">http://developer.android.com/reference/android/media/tv/TvContract.Channels.html#COLUMN_APP_LINK_INTENT_URI</a></p>
5504
5505<p>61. Reference tool documentation (for adb, aapt, ddms, systrace): <a href="http://developer.android.com/tools/help/index.html">http://developer.android.com/tools/help/index.html</a></p>
5506
5507<p>62. Android apk file description: <a href="http://developer.android.com/guide/components/fundamentals.html">http://developer.android.com/guide/components/fundamentals.html</a></p>
5508
5509<p>63. Manifest files: <a href="http://developer.android.com/guide/topics/manifest/manifest-intro.html">http://developer.android.com/guide/topics/manifest/manifest-intro.html</a></p>
5510
5511<p>64. Android Media Formats: <a href="http://developer.android.com/guide/appendix/media-formats.html">http://developer.android.com/guide/appendix/media-formats.html</a></p>
5512
5513<p>65. Android MediaCodecList API: <a href="http://developer.android.com/reference/android/media/MediaCodecList.html">http://developer.android.com/reference/android/media/MediaCodecList.html</a></p>
5514
5515<p>66. Android CamcorderProfile API: <a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">http://developer.android.com/reference/android/media/CamcorderProfile.html</a></p>
5516
5517<p>67. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a></p>
5518
5519<p>68. RTC Hardware Coding Requirements: <a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">http://www.webmproject.org/hardware/rtc-coding-requirements/</a></p>
5520
5521<p>69. AudioEffect API: <a href="http://developer.android.com/reference/android/media/audiofx/AudioEffect.html">http://developer.android.com/reference/android/media/audiofx/AudioEffect.html</a></p>
5522
5523<p>70. Android android.content.pm.PackageManager class and Hardware Features List: <a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">http://developer.android.com/reference/android/content/pm/PackageManager.html</a></p>
5524
5525<p>71. HTTP Live Streaming Draft Protocol: <a href="http://tools.ietf.org/html/draft-pantos-http-live-streaming-03">http://tools.ietf.org/html/draft-pantos-http-live-streaming-03</a></p>
5526
5527<p>72. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a></p>
5528
5529<p>73. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a></p>
5530
5531<p>74. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a></p>
5532
5533<p>75. Monkey testing tool: <a href="http://developer.android.com/tools/help/monkey.html">http://developer.android.com/tools/help/monkey.html</a></p>
5534
5535<p>76. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
5536
5537<p>77. Android Application Development-Related Settings: <a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_APPLICATION_DEVELOPMENT_SETTINGS">http://developer.android.com/reference/android/provider/Settings.html#ACTION_APPLICATION_DEVELOPMENT_SETTINGS</a></p>
5538
5539<p>78. Supporting Multiple Screens: <a href="http://developer.android.com/guide/practices/screens_support.html">http://developer.android.com/guide/practices/screens_support.html</a></p>
5540
5541<p>79. android.util.DisplayMetrics: <a href="http://developer.android.com/reference/android/util/DisplayMetrics.html">http://developer.android.com/reference/android/util/DisplayMetrics.html</a></p>
5542
5543<p>80. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
5544
5545<p>81. Android extension pack for OpenGL ES: <a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">https://developer.android.com/reference/android/opengl/GLES31Ext.html</a></p>
5546
5547<p>82. Hardware Acceleration: <a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">http://developer.android.com/guide/topics/graphics/hardware-accel.html</a></p>
5548
5549<p>83. EGL Extension-EGL_ANDROID_RECORDABLE: <a href="http://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">http://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt</a></p>
5550
5551<p>84. Display Manager: <a href="http://developer.android.com/reference/android/hardware/display/DisplayManager.html">http://developer.android.com/reference/android/hardware/display/DisplayManager.html</a></p>
5552
5553<p>85. android.content.res.Configuration: <a href="http://developer.android.com/reference/android/content/res/Configuration.html">http://developer.android.com/reference/android/content/res/Configuration.html</a></p>
5554
5555<p>86. Touch Input Configuration: <a href="http://source.android.com/devices/tech/input/touch-devices.html">http://source.android.com/devices/tech/input/touch-devices.html</a></p>
5556
5557<p>87. Motion Event API: <a href="http://developer.android.com/reference/android/view/MotionEvent.html">http://developer.android.com/reference/android/view/MotionEvent.html</a></p>
5558
5559<p>88. Key Event API: <a href="http://developer.android.com/reference/android/view/KeyEvent.html">http://developer.android.com/reference/android/view/KeyEvent.html</a></p>
5560
5561<p>89. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
5562
5563<p>90. android.hardware.SensorEvent: <a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">http://developer.android.com/reference/android/hardware/SensorEvent.html</a></p>
5564
5565<p>91. Timestamp sensor event: <a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp</a></p>
5566
5567<p>92. Android Open Source composite sensors: <a href="http://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary</a></p>
5568
5569<p>93. Continuous trigger mode: <a href="http://source.android.com/devices/sensors/report-modes.html#continuous">https://source.android.com/devices/sensors/report-modes.html#continuous</a></p>
5570
5571<p>94. Accelerometer sensor: <a href="http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER">http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER</a></p>
5572
5573<p>95. Android Fingerprint API: <a href="https://developer.android.com/reference/android/hardware/fingerprint/package-summary.html">https://developer.android.com/reference/android/hardware/fingerprint/package-summary.html</a></p>
5574
5575<p>96. Android Fingerprint HAL: <a href="https://source.android.com/devices/tech/security/authentication/fingerprint-hal.html">https://source.android.com/devices/tech/security/authentication/fingerprint-hal.html</a></p>
5576
5577<p>97. Wi-Fi Multicast API: <a href="http://developer.android.com/reference/android/net/wifi/WifiManager.MulticastLock.html">http://developer.android.com/reference/android/net/wifi/WifiManager.MulticastLock.html</a></p>
5578
5579<p>98. Wi-Fi Direct (Wi-Fi P2P): <a href="http://developer.android.com/reference/android/net/wifi/p2p/WifiP2pManager.html">http://developer.android.com/reference/android/net/wifi/p2p/WifiP2pManager.html</a></p>
5580
5581<p>99. WifiManager API: <a href="http://developer.android.com/reference/android/net/wifi/WifiManager.html">http://developer.android.com/reference/android/net/wifi/WifiManager.html</a></p>
5582
5583<p>100. Bluetooth API: <a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">http://developer.android.com/reference/android/bluetooth/package-summary.html</a></p>
5584
5585<p>101. Bluetooth ScanFilter API: <a href="https://developer.android.com/reference/android/bluetooth/le/ScanFilter.html">https://developer.android.com/reference/android/bluetooth/le/ScanFilter.html</a></p>
5586
5587<p>102. NFC Barcode: <a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html</a></p>
5588
5589<p>103. NDEF Push Protocol: <a href="http://source.android.com/compatibility/ndef-push-protocol.pdf">http://source.android.com/compatibility/ndef-push-protocol.pdf</a></p>
5590
5591<p>104. Android Beam: <a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">http://developer.android.com/guide/topics/connectivity/nfc/nfc.html</a></p>
5592
5593<p>105. Android NFC Sharing Settings: <a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS</a></p>
5594
5595<p>106. NFC Connection Handover: <a href="http://members.nfc-forum.org/specs/spec_list/#conn_handover">http://members.nfc-forum.org/specs/spec_list/#conn_handover</a></p>
5596
5597<p>107. Bluetooth Secure Simple Pairing Using NFC: <a href="http://members.nfc-forum.org/apps/group_public/download.php/18688/NFCForum-AD-BTSSP_1_1.pdf">http://members.nfc-forum.org/apps/group_public/download.php/18688/NFCForum-AD-BTSSP_1_1.pdf</a></p>
5598
5599<p>108. Host-based Card Emulation: <a href="http://developer.android.com/guide/topics/connectivity/nfc/hce.html">http://developer.android.com/guide/topics/connectivity/nfc/hce.html</a></p>
5600
5601<p>109. Content Resolver: <a href="http://developer.android.com/reference/android/content/ContentResolver.html">http://developer.android.com/reference/android/content/ContentResolver.html</a></p>
5602
5603<p>110. Camera orientation API: <a href="http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)">http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)</a></p>
5604
5605<p>111. Camera: <a href="http://developer.android.com/reference/android/hardware/Camera.html">http://developer.android.com/reference/android/hardware/Camera.html</a></p>
5606
5607<p>112. Camera: <a href="http://developer.android.com/reference/android/hardware/Camera.Parameters.html">http://developer.android.com/reference/android/hardware/Camera.Parameters.html</a></p>
5608
5609<p>113. Camera hardware level: <a href="https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html#INFO_SUPPORTED_HARDWARE_LEVEL">https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html#INFO_SUPPORTED_HARDWARE_LEVEL</a></p>
5610
5611<p>114. Camera version support: <a href="http://source.android.com/devices/camera/versioning.html">http://source.android.com/devices/camera/versioning.html</a></p>
5612
5613<p>115. Android DownloadManager: <a href="http://developer.android.com/reference/android/app/DownloadManager.html">http://developer.android.com/reference/android/app/DownloadManager.html</a></p>
5614
5615<p>116. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
5616
5617<p>117. Adoptable storage: <a href="http://source.android.com/devices/storage/adoptable.html">http://source.android.com/devices/storage/adoptable.html</a></p>
5618
5619<p>118. Android Open Accessories: <a href="http://developer.android.com/guide/topics/connectivity/usb/accessory.html">http://developer.android.com/guide/topics/connectivity/usb/accessory.html</a></p>
5620
5621<p>119. Android USB Audio: <a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO</a></p>
5622
5623<p>120. USB Charging Specification: <a href="http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf">http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf</a></p>
5624
5625<p>121. USB Host API:<a href="http://developer.android.com/guide/topics/connectivity/usb/host.html"> http://developer.android.com/guide/topics/connectivity/usb/host.html</a></p>
5626
5627<p>122. Wired audio headset: <a href="http://source.android.com/accessories/headset-spec.html">http://source.android.com/accessories/headset-spec.html</a></p>
5628
5629<p>123. Power profile components: <a href="http://source.android.com/devices/tech/power/values.html">http://source.android.com/devices/tech/power/values.html</a></p>
5630
5631<p>124. Batterystats: <a href="http://source.android.com/devices/tech/power/batterystats.html">http://source.android.com/devices/tech/power/batterystats.html</a></p>
5632
5633<p>125. Power usage summary: <a href="http://developer.android.com/reference/android/content/Intent.html#ACTION_POWER_USAGE_SUMMARY">http://developer.android.com/reference/android/content/Intent.html#ACTION_POWER_USAGE_SUMMARY</a></p>
5634
5635<p>126. Android Security and Permissions reference: <a href="http://developer.android.com/guide/topics/security/permissions.html">http://developer.android.com/guide/topics/security/permissions.html</a></p>
5636
5637<p>127. UserManager reference: <a href="http://developer.android.com/reference/android/os/UserManager.html">http://developer.android.com/reference/android/os/UserManager.html</a></p>
5638
5639<p>128. External Storage reference: <a href="http://source.android.com/devices/storage/traditional.html">http://source.android.com/devices/storage</a></p>
5640
5641<p>129. External Storage APIs: <a href="http://developer.android.com/reference/android/os/Environment.html">http://developer.android.com/reference/android/os/Environment.html</a></p>
5642
5643<p>130. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
5644
5645<p>131. Secure lock screen reporting: <a href="http://developer.android.com/reference/android/app/KeyguardManager.html#isDeviceSecure()">http://developer.android.com/reference/android/app/KeyguardManager.html#isDeviceSecure()</a></p>
5646
5647<p>132. Android Open Source Encryption: <a href="http://source.android.com/devices/tech/security/encryption/index.html">http://source.android.com/devices/tech/security/encryption/index.html</a></p>
5648
5649<p>133. Android Keystore System: <a href="https://developer.android.com/training/articles/keystore.html">https://developer.android.com/training/articles/keystore.html</a></p>
5650
5651<p>134. KeyChain API: <a href="https://developer.android.com/reference/android/security/KeyChain.html">https://developer.android.com/reference/android/security/KeyChain.html</a></p>
5652
5653<p>135. Keystore API: <a href="https://developer.android.com/reference/java/security/KeyStore.html">https://developer.android.com/reference/java/security/KeyStore.html</a></p>
5654
5655<p>136. Gatekeeper HAL: <a href="http://source.android.com/devices/tech/security/authentication/gatekeeper.html">http://source.android.com/devices/tech/security/authentication/gatekeeper.html</a></p>
5656
5657<p>137. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
5658
5659<p>138. SystemUpdatePolicy class: <a href="http://developer.android.com/reference/android/app/admin/SystemUpdatePolicy.html">http://developer.android.com/reference/android/app/admin/SystemUpdatePolicy.html</a></p>
5660
5661<p>139. Android Compatibility forum: <a href="https://groups.google.com/forum/#!forum/android-compatibility">https://groups.google.com/forum/#!forum/android-compatibility</a></p>
5662
5663<p>140. Handling app links: <a href="https://developer.android.com/training/app-links">https://developer.android.com/training/app-links/index.html</a></p>
5664
5665<p>141. Google Digital Asset Links: <a href="https://developers.google.com/digital-asset-links">https://developers.google.com/digital-asset-links</a></p>
5666
5667<p>Many of these resources are derived directly or indirectly from the Android
5668SDK, and will be functionally identical to the information in that SDK&rsquo;s
5669documentation. In any cases where this Compatibility Definition or the
5670Compatibility Test Suite disagrees with the SDK documentation, the SDK
5671documentation is considered authoritative. Any technical details provided in
5672the references included above are considered by inclusion to be part of this
5673Compatibility Definition.</p>
5674
5675</div>
5676</body>
5677</html>