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2<head>
3<title>Android ANDROID_VERSION Compatibility Definition</title>
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Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]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_overrides">3.2.3.2. Intent Overrides</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
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]83</div>
84
85<div id="toc_right">
86
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]87<p class="toc_h3"><a href="#3_8_11_dreams">3.8.11. Dreams</a></p>
88
89<p class="toc_h3"><a href="#3_8_12_location">3.8.12. Location</a></p>
90
91<p class="toc_h3"><a href="#3_8_13_unicode_and_font">3.8.13. Unicode and Font</a></p>
92
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]93<p class="toc_h2"><a href="#3_9_device_administration">3.9. Device Administration</a></p>
94
Andy Dyer-smith3d24bbe2015-09-11 15:35:23 +0100[diff] [blame]95<p class="toc_h3"><a href="#3_9_1_device_provisioning">3.9.1 Device Provisioning</a></p>
96
97<p class="toc_h4"><a href="#3_9_1_2_device_owner_provisioning">3.9.1.1 Device Owner provisioning</a></p>
98
99<p class="toc_h4"><a href="#3_9_1_2_managed_profile_provisioning">3.9.1.2 Managed profile provisioning</a></p>
100
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]101<p class="toc_h2"><a href="#3_10_accessibility">3.10. Accessibility</a></p>
102
103<p class="toc_h2"><a href="#3_11_text-to-speech">3.11. Text-to-Speech</a></p>
104
105<p class="toc_h2"><a href="#3_12_tv_input_framework">3.12. TV Input Framework</a></p>
106
107<p class="toc_h1"><a href="#4_application_packaging_compatibility">4. Application Packaging Compatibility</a></p>
108
109<p class="toc_h1"><a href="#5_multimedia_compatibility">5. Multimedia Compatibility</a></p>
110
111<p class="toc_h2"><a href="#5_1_media_codecs">5.1. Media Codecs</a></p>
112
113<p class="toc_h3"><a href="#5_1_1_audio_codecs">5.1.1. Audio Codecs</a></p>
114
115<p class="toc_h3"><a href="#5_1_2_image_codecs">5.1.2. Image Codecs</a></p>
116
117<p class="toc_h3"><a href="#5_1_3_video_codecs">5.1.3. Video Codecs</a></p>
118
119<p class="toc_h2"><a href="#5_2_video_encoding">5.2. Video Encoding</a></p>
120
121<p class="toc_h2"><a href="#5_3_video_decoding">5.3. Video Decoding</a></p>
122
123<p class="toc_h2"><a href="#5_4_audio_recording">5.4. Audio Recording</a></p>
124
125<p class="toc_h3"><a href="#5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</a></p>
126
127<p class="toc_h3"><a href="#5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</a></p>
128
129<p class="toc_h3"><a href="#5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</a></p>
130
131<p class="toc_h2"><a href="#5_5_audio_playback">5.5. Audio Playback</a></p>
132
133<p class="toc_h3"><a href="#5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</a></p>
134
135<p class="toc_h3"><a href="#5_5_2_audio_effects">5.5.2. Audio Effects</a></p>
136
137<p class="toc_h3"><a href="#5_5_3_audio_output_volume">5.5.3. Audio Output Volume</a></p>
138
139<p class="toc_h2"><a href="#5_6_audio_latency">5.6. Audio Latency</a></p>
140
141<p class="toc_h2"><a href="#5_7_network_protocols">5.7. Network Protocols</a></p>
142
143<p class="toc_h2"><a href="#5_8_secure_media">5.8. Secure Media</a></p>
144
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]145<p class="toc_h2"><a href="#5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</a></p>
146
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]147<p class="toc_h2"><a href="#5_10_pro_audio">5.10. Professional Audio</a></p>
148
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]149</div>
150
151<div style="clear: both; page-break-after:always; height:1px"></div>
152
153<div id="toc_left">
154
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]155<p class="toc_h1"><a href="#6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</a></p>
156
157<p class="toc_h2"><a href="#6_1_developer_tools">6.1. Developer Tools</a></p>
158
159<p class="toc_h2"><a href="#6_2_developer_options">6.2. Developer Options</a></p>
160
161<p class="toc_h1"><a href="#7_hardware_compatibility">7. Hardware Compatibility</a></p>
162
163<p class="toc_h2"><a href="#7_1_display_and_graphics">7.1. Display and Graphics</a></p>
164
165<p class="toc_h3"><a href="#7_1_1_screen_configuration">7.1.1. Screen Configuration</a></p>
166
167<p class="toc_h4"><a href="#7_1_1_1_screen_size">7.1.1.1. Screen Size</a></p>
168
169<p class="toc_h4"><a href="#7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</a></p>
170
171<p class="toc_h4"><a href="#7_1_1_3_screen_density">7.1.1.3. Screen Density</a></p>
172
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]173<p class="toc_h3"><a href="#7_1_2_display_metrics">7.1.2. Display Metrics</a></p>
174
175<p class="toc_h3"><a href="#7_1_3_screen_orientation">7.1.3. Screen Orientation</a></p>
176
177<p class="toc_h3"><a href="#7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</a></p>
178
179<p class="toc_h3"><a href="#7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</a></p>
180
181<p class="toc_h3"><a href="#7_1_6_screen_technology">7.1.6. Screen Technology</a></p>
182
183<p class="toc_h3"><a href="#7_1_7_external_displays">7.1.7. Secondary Displays</a></p>
184
185<p class="toc_h2"><a href="#7_2_input_devices">7.2. Input Devices</a></p>
186
187<p class="toc_h3"><a href="#7_2_1_keyboard">7.2.1. Keyboard</a></p>
188
189<p class="toc_h3"><a href="#7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</a></p>
190
191<p class="toc_h3"><a href="#7_2_3_navigation_keys">7.2.3. Navigation Keys</a></p>
192
193<p class="toc_h3"><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen Input</a></p>
194
195<p class="toc_h3"><a href="#7_2_5_fake_touch_input">7.2.5. Fake Touch Input</a></p>
196
197<p class="toc_h3"><a href="#7_2_6_game_controller_support">7.2.6. Game Controller Support</a></p>
198
199<p class="toc_h4"><a href="#7_2_6_1_button_mapping">7.2.6.1. Button Mappings</a></p>
200
201<p class="toc_h3"><a href="#7_2_7_remote_control">7.2.7. Remote Control</a></p>
202
203<p class="toc_h2"><a href="#7_3_sensors">7.3. Sensors</a></p>
204
205<p class="toc_h3"><a href="#7_3_1_accelerometer">7.3.1. Accelerometer</a></p>
206
207<p class="toc_h3"><a href="#7_3_2_magnetometer">7.3.2. Magnetometer</a></p>
208
209<p class="toc_h3"><a href="#7_3_3_gps">7.3.3. GPS</a></p>
210
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]211</div>
212
213<div id="toc_right">
214
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]215<p class="toc_h3"><a href="#7_3_4_gyroscope">7.3.4. Gyroscope</a></p>
216
217<p class="toc_h3"><a href="#7_3_5_barometer">7.3.5. Barometer</a></p>
218
219<p class="toc_h3"><a href="#7_3_6_thermometer">7.3.6. Thermometer</a></p>
220
221<p class="toc_h3"><a href="#7_3_7_photometer">7.3.7. Photometer</a></p>
222
223<p class="toc_h3"><a href="#7_3_8_proximity_sensor">7.3.8. Proximity Sensor</a></p>
224
225<p class="toc_h2"><a href="#7_4_data_connectivity">7.4. Data Connectivity</a></p>
226
227<p class="toc_h3"><a href="#7_4_1_telephony">7.4.1. Telephony</a></p>
228
229<p class="toc_h3"><a href="#7_4_2_ieee_80211_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
230
231<p class="toc_h4"><a href="#7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</a></p>
232
233<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>
234
235<p class="toc_h3"><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></p>
236
237<p class="toc_h3"><a href="#7_4_4_near-field_communications">7.4.4. Near-Field Communications</a></p>
238
239<p class="toc_h3"><a href="#7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</a></p>
240
241<p class="toc_h3"><a href="#7_4_6_sync_settings">7.4.6. Sync Settings</a></p>
242
243<p class="toc_h2"><a href="#7_5_cameras">7.5. Cameras</a></p>
244
245<p class="toc_h3"><a href="#7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</a></p>
246
247<p class="toc_h3"><a href="#7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</a></p>
248
249<p class="toc_h3"><a href="#7_5_3_external_camera">7.5.3. External Camera</a></p>
250
251<p class="toc_h3"><a href="#7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</a></p>
252
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]253<p class="toc_h3"><a href="#7_5_5_camera_orientation">7.5.5. Camera Orientation</a></p>
254
255<p class="toc_h2"><a href="#7_6_memory_and_storage">7.6. Memory and Storage</a></p>
256
257<p class="toc_h3"><a href="#7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</a></p>
258
259<p class="toc_h3"><a href="#7_6_2_application_shared_storage">7.6.2. Application Shared Storage</a></p>
260
261<p class="toc_h2"><a href="#7_7_usb">7.7. USB</a></p>
262
263<p class="toc_h2"><a href="#7_8_audio">7.8. Audio</a></p>
264
265<p class="toc_h3"><a href="#7_8_1_microphone">7.8.1. Microphone</a></p>
266
267<p class="toc_h3"><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></p>
268
269<p class="toc_h4"><a href="#7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</a></p>
270
271<p class="toc_h1"><a href="#8_performance_compatibility">8. Performance Compatibility</a></p>
272
273<p class="toc_h2"><a href="#8_1_user_experience_consistency">8.1. User Experience Consistency</a></p>
274
275<p class="toc_h2"><a href="#8_2_memory_performance">8.2. Memory Performance</a></p>
276
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]277</div>
278
279<div style="clear: both; page-break-after:always; height:1px"></div>
280
281<div id="toc_left">
282
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]283<p class="toc_h1"><a href="#9_security_model_compatibility">9. Security Model Compatibility</a></p>
284
285<p class="toc_h2"><a href="#9_1_permissions">9.1. Permissions</a></p>
286
287<p class="toc_h2"><a href="#9_2_uid_and_process_isolation">9.2. UID and Process Isolation</a></p>
288
289<p class="toc_h2"><a href="#9_3_filesystem_permissions">9.3. Filesystem Permissions</a></p>
290
291<p class="toc_h2"><a href="#9_4_alternate_execution_environments">9.4. Alternate Execution Environments</a></p>
292
293<p class="toc_h2"><a href="#9_5_multi-user_support">9.5. Multi-User Support</a></p>
294
295<p class="toc_h2"><a href="#9_6_premium_sms_warning">9.6. Premium SMS Warning</a></p>
296
297<p class="toc_h2"><a href="#9_7_kernel_security_features">9.7. Kernel Security Features</a></p>
298
299<p class="toc_h2"><a href="#9_8_privacy">9.8. Privacy</a></p>
300
301<p class="toc_h2"><a href="#9_9_full-disk-encryption">9.9. Full-Disk Encryption</a></p>
302
303<p class="toc_h2"><a href="#9_10_verified_boot">9.10. Verified Boot</a></p>
304
305<p class="toc_h1"><a href="#10_software_compatibility_testing">10. Software Compatibility Testing</a></p>
306
307<p class="toc_h2"><a href="#10_1_compatibility_test_suite">10.1. Compatibility Test Suite</a></p>
308
309<p class="toc_h2"><a href="#10_2_cts_verifier">10.2. CTS Verifier</a></p>
310
311<p class="toc_h1"><a href="#11_updatable_software">11. Updatable Software</a></p>
312
313<p class="toc_h1"><a href="#12_document_changelog">12. Document Changelog</a></p>
314
315<p class="toc_h1"><a href="#13_contact_us">13. Contact Us</a></p>
316
317<p class="toc_h1"><a href="#14_resources">14. Resources</a></p>
318
319</div>
320
321</div>
322
323<div style="clear: both"></div>
324
325<div id="main">
326
327<h1 id="1_introduction">1. Introduction</h1>
328
329
330<p>This document enumerates the requirements that must be met in order for devices
331to be compatible with Android ANDROID_VERSION.</p>
332
333<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
334defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
335
336<p>As used in this document, a &ldquo;device implementer&rdquo; or &ldquo;implementer&rdquo; is a person
337or organization developing a hardware/software solution running Android ANDROID_VERSION. A
338&ldquo;device implementation&rdquo; or &ldquo;implementation is the hardware/software solution
339so developed.</p>
340
341<p>To be considered compatible with Android ANDROID_VERSION, device implementations MUST meet
342the requirements presented in this Compatibility Definition, including any
343documents incorporated via reference.</p>
344
345<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
346implementer to ensure compatibility with existing implementations.</p>
347
348<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
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]349implementers are STRONGLY RECOMMENDED to base their implementations to the
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]350greatest extent possible on the &ldquo;upstream&rdquo; source code available from the
351Android Open Source Project. While some components can hypothetically be
352replaced with alternate implementations this practice is strongly discouraged,
353as passing the software tests will become substantially more difficult. It is
354the implementer&rsquo;s responsibility to ensure full behavioral compatibility with
355the standard Android implementation, including and beyond the Compatibility
356Test Suite. Finally, note that certain component substitutions and
357modifications are explicitly forbidden by this document.</p>
358
359<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
360functionally identical to the information in that SDK&rsquo;s documentation. For any
361case where this Compatibility Definition or the Compatibility Test Suite
362disagrees with the SDK documentation, the SDK documentation is considered
363authoritative. 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>
364
365<h1 id="2_device_types">2. Device Types</h1>
366
367
368<p>While the Android Open Source Project has been used in the implementation of a
369variety of device types and form factors, many aspects of the architecture and
370compatibility requirements were optimized for handheld devices. Starting from
371Android 5.0, the Android Open Source Project aims to embrace a wider variety of
372device types as described in this section.</p>
373
374<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
375it in the hand, such as mp3 players, phones, and tablets. Android Handheld
376device implementations:</p>
377
378<ul>
379 <li>MUST have a touchscreen embedded in the device.</li>
380 <li>MUST have a power source that provides mobility, such as a battery.</li>
381</ul>
382
383<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
384for consuming digital media, movies, games, apps, and/or live TV for users
385sitting about ten feet away (a &ldquo;lean back&rdquo; or &ldquo;10-foot user interface&rdquo;).
386Android Television devices:</p>
387
388<ul>
389 <li>MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
390or a wireless port for display.</li>
391 <li>MUST declare the features android.software.leanback and
392android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>].</li>
393</ul>
394
395<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
396perhaps on the wrist, and:</p>
397
398<ul>
399 <li>MUST have a screen with the physical diagonal length in the range from 1.1 to
4002.5 inches.</li>
401 <li>MUST declare the feature android.hardware.type.watch.</li>
402 <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>
403</ul>
404
405<p><strong>Android Automotive implementation</strong> refers to a vehicle head
406unit running Android as an operating system for part or all of the system and/or
407infotainment functionality. Android Automotive implementations MUST support
408uiMode = UI_MODE_TYPE_CAR [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">Resources, 111</a>].</p>
409
410<p>All Android device implementations that do not fit into any of the above device
411types still MUST meet all requirements in this document to be Android ANDROID_VERSION
412compatible, unless the requirement is explicitly described to be only
413applicable to a specific Android device type from above.</p>
414
415<h2 id="2_1_device_configurations">2.1 Device Configurations</h2>
416
417
418<p>This is a summary of major differences in hardware configuration by device
419type. (Empty cells denote a &ldquo;MAY&rdquo;). Not all configurations are covered in this
420table; see relevant hardware sections for more detail.</p>
421<table>
422 <tr>
423 <th>Category</th>
424 <th>Feature</th>
425 <th>Section</th>
426 <th>Handheld</th>
427 <th>Television</th>
428 <th>Watch</th>
429 <th>Automotive</th>
430 <th>Other</th>
431 </tr>
432 <tr>
433 <td rowspan="3">Input</td>
434 <td>D-pad</td>
435 <td><a href="#7_2_2_non-touch-navigation">7.2.2. Non-touch Navigation</a></td>
436 <td></td>
437 <td>MUST</td>
438 <td></td>
439 <td></td>
440 <td></td>
441 </tr>
442 <tr>
443 <td>Touchscreen </td>
444 <td><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen input</a></td>
445 <td>MUST</td>
446 <td></td>
447 <td>MUST</td>
448 <td></td>
449 <td>SHOULD</td>
450 </tr>
451 <tr>
452 <td>Microphone </td>
453 <td><a href="#7_8_1_microphone">7.8.1. Microphone</a></td>
454 <td>MUST</td>
455 <td>SHOULD </td>
456 <td>MUST</td>
457 <td>MUST</td>
458 <td>SHOULD</td>
459 </tr>
460 <tr>
461 <td rowspan="2">Sensors</td>
462 <td>Accelerometer </td>
463 <td><a href="#7_3_1_accelerometer">7.3.1 Accelerometer</a></td>
464 <td>SHOULD</td>
465 <td></td>
466 <td>SHOULD</td>
467 <td></td>
468 <td>SHOULD</td>
469 </tr>
470 <tr>
471 <td>GPS</td>
472 <td><a href="#7_3_3_gps">7.3.3. GPS</a></td>
473 <td>SHOULD</td>
474 <td></td>
475 <td></td>
476 <td>SHOULD</td>
477 <td></td>
478 </tr>
479 <tr>
480 <td rowspan="5">Connectivity</td>
481 <td>Wi-Fi</td>
482 <td><a href="#7_4_2_ieee_802.11">7.4.2. IEEE 802.11</a></td>
483 <td>SHOULD</td>
484 <td> MUST</td>
485 <td></td>
486 <td>SHOULD</td>
487 <td>SHOULD</td>
488 </tr>
489 <tr>
490 <td>Wi-Fi Direct</td>
491 <td><a href="#7_4_2_1_wi-fi-direct">7.4.2.1. Wi-Fi Direct</a></td>
492 <td>SHOULD</td>
493 <td>SHOULD</td>
494 <td></td>
495 <td></td>
496 <td>SHOULD</td>
497 </tr>
498 <tr>
499 <td>Bluetooth</td>
500 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
501 <td>SHOULD</td>
502 <td>MUST</td>
503 <td>MUST</td>
504 <td>MUST</td>
505 <td>SHOULD</td>
506 </tr>
507 <tr>
508 <td>Bluetooth Low Energy</td>
509 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
510 <td>SHOULD</td>
511 <td>MUST</td>
512 <td>SHOULD</td>
513 <td>SHOULD</td>
514 <td>SHOULD</td>
515 </tr>
516 <tr>
517 <td>USB peripheral/host mode</td>
518 <td><a href="#7_7_usb">7.7. USB</a></td>
519 <td>SHOULD</td>
520 <td></td>
521 <td></td>
522 <td>SHOULD</td>
523 <td>SHOULD</td>
524 </tr>
525 <tr>
526 <td>Output</td>
527 <td>Speaker and/or Audio output ports</td>
528 <td><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></td>
529 <td>MUST</td>
530 <td>MUST</td>
531 <td></td>
532 <td>MUST</td>
533 <td>MUST</td>
534 </tr>
535</table>
536
537
538<h1 id="3_software">3. Software</h1>
539
540
541<h2 id="3_1_managed_api_compatibility">3.1. Managed API Compatibility</h2>
542
543
544<p>The managed Dalvik bytecode execution environment is the primary vehicle for
545Android applications. The Android application programming interface (API) is
546the set of Android platform interfaces exposed to applications running in the
547managed runtime environment. Device implementations MUST provide complete
548implementations, including all documented behaviors, of any documented API
549exposed by the Android SDK [<a href="http://developer.android.com/reference/packages.html">Resources, 5</a>] or any API decorated with the &ldquo;@SystemApi&rdquo; marker in the upstream Android
550source code. </p>
551
552<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
553signatures, deviate from the documented behavior, or include no-ops, except
554where specifically allowed by this Compatibility Definition.</p>
555
556<p>This Compatibility Definition permits some types of hardware for which Android
557includes APIs to be omitted by device implementations. In such cases, the APIs
558MUST 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>
559
560<h2 id="3_2_soft_api_compatibility">3.2. Soft API Compatibility</h2>
561
562
563<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
564such things as intents, permissions, and similar aspects of Android
565applications that cannot be enforced at application compile time.</p>
566
567<h3 id="3_2_1_permissions">3.2.1. Permissions</h3>
568
569
570<p>Device implementers MUST support and enforce all permission constants as
571documented by the Permission reference page [<a href="http://developer.android.com/reference/android/Manifest.permission.html">Resources, 6]</a>. Note that <a href="#9_security_model_compatibility">section 9</a> lists additional requirements related to the Android security model.</p>
572
573<h3 id="3_2_2_build_parameters">3.2.2. Build Parameters</h3>
574
575
576<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, 7</a>] that are intended to describe the current device. To provide consistent,
577meaningful values across device implementations, the table below includes
578additional restrictions on the formats of these values to which device
579implementations MUST conform.</p>
580<table>
581 <tr>
582 <th>Parameter</th>
583 <th>Details</th>
584 </tr>
585 <tr>
586 <td>VERSION.RELEASE</td>
587 <td>The version of the currently-executing Android system, in human-readable
588format. This field MUST have one of the string values defined in [<a href="http://source.android.com/compatibility/ANDROID_VERSION/versions.html">Resources, 8]</a>.</td>
589 </tr>
590 <tr>
591 <td>VERSION.SDK</td>
592 <td>The version of the currently-executing Android system, in a format accessible
593to third-party application code. For Android ANDROID_VERSION, this field MUST have the
Unsuk Jung8bebb3e2015-09-29 22:10:23 -0700[diff] [blame]594integer value ANDROID_VERSION_INT.</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]595 </tr>
596 <tr>
597 <td>VERSION.SDK_INT</td>
598 <td>The version of the currently-executing Android system, in a format accessible
599to third-party application code. For Android ANDROID_VERSION, this field MUST have the
Unsuk Jung8bebb3e2015-09-29 22:10:23 -0700[diff] [blame]600integer value ANDROID_VERSION_INT.</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]601 </tr>
602 <tr>
603 <td>VERSION.INCREMENTAL</td>
604 <td>A value chosen by the device implementer designating the specific build of the
605currently-executing Android system, in human-readable format. This value MUST
606NOT be reused for different builds made available to end users. A typical use
607of this field is to indicate which build number or source-control change
608identifier was used to generate the build. There are no requirements on the
609specific format of this field, except that it MUST NOT be null or the empty
610string ("").</td>
611 </tr>
612 <tr>
613 <td>BOARD</td>
614 <td>A value chosen by the device implementer identifying the specific internal
615hardware used by the device, in human-readable format. A possible use of this
616field is to indicate the specific revision of the board powering the device.
617The value of this field MUST be encodable as 7-bit ASCII and match the regular
618expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
619 </tr>
620 <tr>
621 <td>BRAND</td>
622 <td>A value reflecting the brand name associated with the device as known to the
623end users. MUST be in human-readable format and SHOULD represent the
624manufacturer of the device or the company brand under which the device is
625marketed. The value of this field MUST be encodable as 7-bit ASCII and match
626the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
627 </tr>
628 <tr>
629 <td>SUPPORTED_ABIS</td>
630 <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>
631 </tr>
632 <tr>
633 <td>SUPPORTED_32_BIT_ABIS</td>
634 <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>
635 </tr>
636 <tr>
637 <td>SUPPORTED_64_BIT_ABIS</td>
638 <td>The name of the second instruction set (CPU type + ABI convention) of native
639code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
640 </tr>
641 <tr>
642 <td>CPU_ABI</td>
643 <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>
644 </tr>
645 <tr>
646 <td>CPU_ABI2</td>
647 <td>The name of the second instruction set (CPU type + ABI convention) of native
648code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
649 </tr>
650 <tr>
651 <td>DEVICE</td>
652 <td>A value chosen by the device implementer containing the development name or
653code name identifying the configuration of the hardware features and industrial
654design of the device. The value of this field MUST be encodable as 7-bit ASCII
655and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
656 </tr>
657 <tr>
658 <td>FINGERPRINT</td>
659 <td>A string that uniquely identifies this build. It SHOULD be reasonably
660human-readable. It MUST follow this template:</p>
661
662<p class="small">$(BRAND)/$(PRODUCT)/$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
663
664<p>For example: acme/myproduct/mydevice:ANDROID_VERSION/LMYXX/3359:userdebug/test-keys</p>
665
666<p>The fingerprint MUST NOT include whitespace characters. If other fields
667included in the template above have whitespace characters, they MUST be
668replaced in the build fingerprint with another character, such as the
669underscore ("_") character. The value of this field MUST be encodable as 7-bit
670ASCII.</td>
671 </tr>
672 <tr>
673 <td>HARDWARE</td>
674 <td>The name of the hardware (from the kernel command line or /proc). It SHOULD be
675reasonably human-readable. The value of this field MUST be encodable as 7-bit
676ASCII and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;. </td>
677 </tr>
678 <tr>
679 <td>HOST</td>
680 <td>A string that uniquely identifies the host the build was built on, in
681human-readable format. There are no requirements on the specific format of this
682field, except that it MUST NOT be null or the empty string ("").</td>
683 </tr>
684 <tr>
685 <td>ID</td>
686 <td>An identifier chosen by the device implementer to refer to a specific release,
687in human-readable format. This field can be the same as
688android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
689meaningful for end users to distinguish between software builds. The value of
690this field MUST be encodable as 7-bit ASCII and match the regular expression &ldquo;^[a-zA-Z0-9._-]+$&rdquo;.</td>
691 </tr>
692 <tr>
693 <td>MANUFACTURER</td>
694 <td>The trade name of the Original Equipment Manufacturer (OEM) of the product.
695There are no requirements on the specific format of this field, except that it
696MUST NOT be null or the empty string ("").</td>
697 </tr>
698 <tr>
699 <td>MODEL</td>
700 <td>A value chosen by the device implementer containing the name of the device as
701known to the end user. This SHOULD be the same name under which the device is
702marketed and sold to end users. There are no requirements on the specific
703format of this field, except that it MUST NOT be null or the empty string ("").</td>
704 </tr>
705 <tr>
706 <td>PRODUCT</td>
707 <td>A value chosen by the device implementer containing the development name or
708code name of the specific product (SKU) that MUST be unique within the same
709brand. MUST be human-readable, but is not necessarily intended for view by end
710users. The value of this field MUST be encodable as 7-bit ASCII and match the
711regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
712 </tr>
713 <tr>
714 <td>SERIAL</td>
Owain Davies4f8796e2015-09-24 14:01:26 +0100[diff] [blame]715 <td>A hardware serial number, which MUST be available and unique across
716devices with the same MODEL and MANUFACTURER. The value of this field MUST
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]717be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
718 </tr>
719 <tr>
720 <td>TAGS</td>
721 <td>A comma-separated list of tags chosen by the device implementer that further
722distinguishes the build. This field MUST have one of the values corresponding
723to the three typical Android platform signing configurations: release-keys,
724dev-keys, test-keys. </td>
725 </tr>
726 <tr>
727 <td>TIME</td>
728 <td>A value representing the timestamp of when the build occurred.</td>
729 </tr>
730 <tr>
731 <td>TYPE</td>
732 <td>A value chosen by the device implementer specifying the runtime configuration
733of the build. This field MUST have one of the values corresponding to the three
734typical Android runtime configurations: user, userdebug, or eng.</td>
735 </tr>
736 <tr>
737 <td>USER</td>
738 <td>A name or user ID of the user (or automated user) that generated the build.
739There are no requirements on the specific format of this field, except that it
740MUST NOT be null or the empty string ("").</td>
741 </tr>
742</table>
743
744
745<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
746
747
748<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
749described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
750implementer MUST provide an Android Activity or Service that specifies a
751matching intent filter that binds to and implements correct behavior for each
752specified intent pattern.</p>
753
754<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
755
756
757<p>Android intents allow application components to request functionality from
758other Android components. The Android upstream project includes a list of
759applications considered core Android applications, which implements several
760intent patterns to perform common actions. The core Android applications are:</p>
761
762<ul>
763 <li>Desk Clock</li>
764 <li>Browser</li>
765 <li>Calendar</li>
766 <li>Contacts</li>
767 <li>Gallery</li>
768 <li>GlobalSearch</li>
769 <li>Launcher</li>
770 <li>Music</li>
771 <li>Settings</li>
772</ul>
773
774<p>Device implementations SHOULD include the core Android applications as
775appropriate but MUST include a component implementing the same intent patterns
776defined by all the &ldquo;public&rdquo; Activity or Service components of these core
777Android applications. Note that Activity or Service components are considered
778&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
779
780<h4 id="3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</h4>
781
782
783<p>As Android is an extensible platform, device implementations MUST allow each
784intent pattern referenced in <a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a> to be overridden by third-party applications. The upstream Android open source
785implementation allows this by default; device implementers MUST NOT attach
786special privileges to system applications' use of these intent patterns, or
787prevent third-party applications from binding to and assuming control of these
788patterns. This prohibition specifically includes but is not limited to
789disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
790multiple applications that all handle the same intent pattern.</p>
791
792<p>However, device implementations MAY provide default activities for specific URI
793patterns (eg. http://play.google.com) if the default activity provides a more
794specific filter for the data URI. For example, an intent filter specifying the
795data URI &ldquo;http://www.android.com&rdquo; is more specific than the browser filter for&ldquo;http://&rdquo;. Device implementations MUST provide a user interface for users to
796modify the default activity for intents.</p>
797
798<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
799
800
801<p>Device implementations MUST NOT include any Android component that honors any
802new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
803string in the android.* or com.android.* namespace. Device implementers MUST
804NOT include any Android components that honor any new intent or broadcast
805intent patterns using an ACTION, CATEGORY, or other key string in a package
806space belonging to another organization. Device implementers MUST NOT alter or
807extend 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
808and obviously associated with their own organization. This prohibition is
809analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
810
811<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
812
813
814<p>Third-party applications rely on the platform to broadcast certain intents to
815notify them of changes in the hardware or software environment.
816Android-compatible devices MUST broadcast the public broadcast intents in
817response to appropriate system events. Broadcast intents are described in the
818SDK documentation.</p>
819
820<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
821
822
823<p>Android includes settings that provide users an easy way to select their
824default applications, for example for Home screen or SMS. Where it makes sense,
825device implementations MUST provide a similar settings menu and be compatible
826with the intent filter pattern and API methods described in the SDK
827documentation as below.</p>
828
829<p>Device implementations:</p>
830
831<ul>
832 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
833settings menu for Home Screen, if the device implementation reports
834android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
835 <li>MUST provide a settings menu that will call the
836android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
837change the default SMS application, if the device implementation reports
838android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]</li>
839 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
840app settings menu for Tap and Pay, if the device implementation reports
841android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
842</ul>
843
844<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
845
846
847<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
848
849
850<p>Managed Dalvik bytecode can call into native code provided in the application
851.apk file as an ELF .so file compiled for the appropriate device hardware
852architecture. As native code is highly dependent on the underlying processor
853technology, Android defines a number of Application Binary Interfaces (ABIs) in
854the Android NDK. Device implementations MUST be compatible with one or more
855defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
856
857<p>If a device implementation includes support for an Android ABI, it:</p>
858
859<ul>
860 <li>MUST include support for code running in the managed environment to call into
861native code, using the standard Java Native Interface (JNI) semantics</li>
862 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
863the ABI) with each required library in the list below</li>
864 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
865 <li>MUST accurately report the native Application Binary Interface (ABI) supported
866by the device, via the android.os.Build.SUPPORTED_ABIS,
867android.os.Build.SUPPORTED_32_BIT_ABIS, and
868android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
869of ABIs ordered from the most to the least preferred one</li>
Unsuk Jung06706432015-08-31 11:26:13 -0700[diff] [blame]870 <li>MUST report, via the above parameters, only those ABIs documented and
871described in the latest version of the Android NDK ABI Management documentation
872[<a href="https://developer.android.com/ndk/guides/abis.html">Resources, XX</a>],
873and MUST include support for the Advanced SIMD (a.k.a. NEON)
874[<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">Resources,XX</a>]
875extension
876 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]877 <li>SHOULD be built using the source code and header files available in the
878upstream Android Open Source Project</li>
879</ul>
880
881<p>The following native code APIs MUST be available to apps that include native
882code:</p>
883
884<ul>
885 <li>libc (C library)</li>
886 <li>libm (math library)</li>
887 <li>Minimal support for C++</li>
888 <li>JNI interface</li>
889 <li>liblog (Android logging)</li>
890 <li>libz (Zlib compression)</li>
891 <li>libdl (dynamic linker)</li>
892 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
893 <li>libGLESv2.so (OpenGL ES 2.0)</li>
894 <li>libGLESv3.so (OpenGL ES 3.x)</li>
895 <li>libEGL.so (native OpenGL surface management)</li>
896 <li>libjnigraphics.so</li>
897 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
898 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
899 <li>libandroid.so (native Android activity support)</li>
900 <li>libmediandk.so (native media APIs support)</li>
901 <li>Support for OpenGL, as described below</li>
902</ul>
903
904<p>Note that future releases of the Android NDK may introduce support for
905additional ABIs. If a device implementation is not compatible with an existing
906predefined ABI, it MUST NOT report support for any ABIs at all.</p>
907
908<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
909(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
910Android Extension Pack [<a href="http://developer.android.com/guide/topics/graphics/opengl.html#aep">Resources, 11</a>] function symbols as defined in the NDK release android-21. Although all the
911symbols must be present, only the corresponding functions for OpenGL ES
912versions and extensions actually supported by the device must be fully
913implemented.</p>
914
Unsuk Jung6f6ac762015-09-29 14:28:03 -0700[diff] [blame]915<p>Device implementations MUST NOT include a native library with the
916name libvulkan.so.</p>
917
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]918<p>Native code compatibility is challenging. For this reason, device implementers
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]919are <strong>STRONGLY RECOMMENDED</strong> to use the implementations of the libraries listed above from the upstream
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]920Android Open Source Project. </p>
921
922<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9233.3.2. 32-bit ARM Native Code Compatibility
924</h3>
925
926<p>The ARMv8 architecture deprecates several CPU operations, including some
927operations used in existing native code. On 64-bit ARM devices, the following
928deprecated operations MUST remain available to 32-bit native ARM code, either
929through native CPU support or through software emulation:</p>
930
931<ul>
932<li>SWP and SWPB instructions</li>
933<li>SETEND instruction</li>
934<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
935</ul>
936
937<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
938from 32-bit ARM native code. For compatibility with applications built using this
939NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
940by 32-bit ARM applications:</p>
941
942<ul>
943<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
944supported by the device</li>
945<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
946highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
947</ul>
948
949<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
950applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
951non-ARM applications.</p>
952
953<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
954
955
956<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
957
958<div class="note">
959<p>Android Watch devices MAY, but all other device implementations MUST provide
960a complete implementation of the android.webkit.Webview API.</p>
961</div>
962
963
964<p>The platform feature android.software.webview MUST be reported on any device
965that provides a complete implementation of the android.webkit.WebView API, and
966MUST NOT be reported on devices without a complete implementation of the API.
967The Android Open Source implementation uses code from the Chromium Project to
968implement the android.webkit.WebView [<a href="http://developer.android.com/reference/android/webkit/WebView.html">Resources, 12</a>]. Because it is not feasible to develop a comprehensive test suite for a web
969rendering system, device implementers MUST use the specific upstream build of
970Chromium in the WebView implementation. Specifically:</p>
971
972<ul>
973 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
974build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
975includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
976 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung34d4dcb2015-09-28 15:41:27 -0700[diff] [blame]977<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD); wv)
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]978AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
979Safari/537.36</p>
980 <ul>
981 <li>The value of the $(VERSION) string MUST be the same as the value for
982android.os.Build.VERSION.RELEASE.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]983 <li>The value of the $(MODEL) string MUST be the same as the value for
984android.os.Build.MODEL.</li>
985 <li>The value of the $(BUILD) string MUST be the same as the value for
986android.os.Build.ID.</li>
987 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
988upstream Android Open Source Project.</li>
989 <li>Device implementations MAY omit Mobile in the user agent string.</li>
990 </ul></li></ul>
991
992<p>The WebView component SHOULD include support for as many HTML5 features as
993possible and if it supports the feature SHOULD conform to the HTML5
994specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
995
996<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
997
998<div class="note">
999<p>Android Television, Watch, and Android Automotive implementations MAY omit a
1000browser application, but MUST support the public intent patterns as described in
1001<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
1002of device implementations MUST include a standalone Browser application for
1003general user web browsing.</p>
1004</div>
1005
1006<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1007However, even if an alternate Browser application is used, the
1008android.webkit.WebView component provided to third-party applications MUST be
1009based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1010
1011<p>Implementations MAY ship a custom user agent string in the standalone Browser
1012application.</p>
1013
1014<p>The standalone Browser application (whether based on the upstream WebKit
1015Browser application or a third-party replacement) SHOULD include support for as
1016much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1017APIs associated with HTML5:</p>
1018
1019<ul>
1020 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1021 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1022 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1023</ul>
1024
1025<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1026[<a href="http://www.w3.org/TR/webstorage/">Resources, 18</a>], and SHOULD support the HTML5/W3C IndexedDB API [<a href="http://www.w3.org/TR/IndexedDB/">Resources, 19</a>]. Note that as the web development standards bodies are transitioning to favor
1027IndexedDB over webstorage, IndexedDB is expected to become a required component
1028in a future version of Android.</p>
1029
1030<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1031
1032
1033<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1034consistent with the preferred implementation of the upstream Android Open
1035Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1036
1037<ul>
1038 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1039 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1040type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1041 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1042</ul>
1043
1044<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1045significant portions of the platform for behavioral compatibility, but not all.
1046It is the responsibility of the implementer to ensure behavioral compatibility
1047with the Android Open Source Project. For this reason, device implementers
1048SHOULD use the source code available via the Android Open Source Project where
1049possible, rather than re-implement significant parts of the system.</p>
1050
1051<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1052
1053
1054<p>Android follows the package and class namespace conventions defined by the Java
1055programming language. To ensure compatibility with third-party applications,
1056device implementers MUST NOT make any prohibited modifications (see below) to
1057these package namespaces:</p>
1058
1059<ul>
1060 <li>java.*</li>
1061 <li>javax.*</li>
1062 <li>sun.*</li>
1063 <li>android.*</li>
1064 <li>com.android.*</li>
1065</ul>
1066
1067<p><strong>Prohibited modifications include</strong>:</p>
1068
1069<ul>
1070 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1071platform by changing any method or class signatures, or by removing classes or
1072class fields.</li>
1073 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1074such modifications MUST NOT impact the stated behavior and Java-language
1075signature of any publicly exposed APIs.</li>
1076 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1077or interfaces, or fields or methods to existing classes or interfaces) to the
1078APIs above.</li>
1079</ul>
1080
1081<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,
1082device implementers MUST NOT expose new APIs or alter existing APIs in the
1083namespaces noted above. Device implementers MAY make internal-only
1084modifications, but those modifications MUST NOT be advertised or otherwise
1085exposed to developers.</p>
1086
1087<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1088namespace owned by or referring to another organization. For instance, device
1089implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1090Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1091namespaces. Additionally, if a device implementation includes custom APIs
1092outside the standard Android namespace, those APIs MUST be packaged in an
1093Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1094lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1095APIs.</p>
1096
1097<p>If a device implementer proposes to improve one of the package namespaces above
1098(such as by adding useful new functionality to an existing API, or adding a new
1099API), 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
1100information on that site.</p>
1101
1102<p>Note that the restrictions above correspond to standard conventions for naming
1103APIs in the Java programming language; this section simply aims to reinforce
1104those conventions and make them binding through inclusion in this Compatibility
1105Definition.</p>
1106
1107<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1108
1109
1110<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1111Dalvik bytecode specification and semantics [<a href="https://android.googlesource.com/platform/dalvik/+/lollipop-release/docs/">Resources, 20</a>]. Device implementers SHOULD use ART, the reference upstream implementation of
1112the Dalvik Executable Format, and the reference implementation&rsquo;s package
1113management system.</p>
1114
1115<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1116accordance with the upstream Android platform, and as specified by the
1117following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1118
1119<p>Note that memory values specified below are considered minimum values and
1120device implementations MAY allocate more memory per application.</p>
1121
1122<table>
1123 <tr>
1124 <th>Screen Layout</th>
1125 <th>Screen Density</th>
1126 <th>Minimum Application Memory</th>
1127 </tr>
1128 <tr>
1129 <td rowspan="10">small/normal</td>
1130 <td>120 dpi (ldpi)</td>
1131 <td rowspan="2">32MB</td>
1132 </tr>
1133 <tr>
1134 <td>160 dpi (mdpi)</td>
1135 </tr>
1136 <tr>
1137 <td>213 dpi (tvdpi)</td>
1138 <td rowspan="3">48MB</td>
1139 </tr>
1140 <tr>
1141 <td>240 dpi (hdpi)</td>
1142 </tr>
1143 <tr>
1144 <td>280 dpi (280dpi)</td>
1145 </tr>
1146 <tr>
1147 <td>320 dpi (xhdpi)</td>
1148 <td>80MB</td>
1149 </tr>
1150 <tr>
1151 <td>400 dpi (400dpi)</td>
1152 <td>96MB</td>
1153 </tr>
1154 <tr>
1155 <td>480 dpi (xxhdpi)</td>
1156 <td>128MB</td>
1157 </tr>
1158 <tr>
1159 <td>560 dpi (560dpi)</td>
1160 <td>192MB</td>
1161 </tr>
1162 <tr>
1163 <td>640 dpi (xxxhdpi)</td>
1164 <td>256MB</td>
1165 </tr>
1166 <tr>
1167 <td rowspan="10">large</td>
1168 <td>120 dpi (ldpi)</td>
1169 <td>32MB</td>
1170 </tr>
1171 <tr>
1172 <td>160 dpi (mdpi)</td>
1173 <td>48MB</td>
1174 </tr>
1175 <tr>
1176 <td>213 dpi (tvdpi)</td>
1177 <td rowspan="2">80MB</td>
1178 </tr>
1179 <tr>
1180 <td>240 dpi (hdpi)</td>
1181 </tr>
1182 <tr>
1183 <td>280 dpi (280dpi)</td>
1184 <td>96MB</td>
1185 </tr>
1186 <tr>
1187 <td>320 dpi (xhdpi)</td>
1188 <td>128MB</td>
1189 </tr>
1190 <tr>
1191 <td>400 dpi (400dpi)</td>
1192 <td>192MB</td>
1193 </tr>
1194 <tr>
1195 <td>480 dpi (xxhdpi)</td>
1196 <td>256MB</td>
1197 </tr>
1198 <tr>
1199 <td>560 dpi (560dpi)</td>
1200 <td>384MB</td>
1201 </tr>
1202 <tr>
1203 <td>640 dpi (xxxhdpi)</td>
1204 <td>512MB</td>
1205 </tr>
1206 <tr>
1207 <td rowspan="10">xlarge</td>
1208 <td>120 dpi (ldpi)</td>
1209 <td>48MB</td>
1210 </tr>
1211 <tr>
1212 <td>160 dpi (mdpi)</td>
1213 <td>80MB</td>
1214 </tr>
1215 <tr>
1216 <td>213 dpi (tvdpi)</td>
1217 <td rowspan="2">96MB</td>
1218 </tr>
1219 <tr>
1220 <td>240 dpi (hdpi)</td>
1221 </tr>
1222 <tr>
1223 <td>280 dpi (280dpi)</td>
1224 <td>144MB</td>
1225 </tr>
1226 <tr>
1227 <td>320 dpi (xhdpi)</td>
1228 <td>192MB</td>
1229 </tr>
1230 <tr>
1231 <td>400 dpi (400dpi)</td>
1232 <td>288MB</td>
1233 </tr>
1234 <tr>
1235 <td>480 dpi (xxhdpi)</td>
1236 <td>384MB</td>
1237 </tr>
1238 <tr>
1239 <td>560 dpi (560dpi)</td>
1240 <td>576MB</td>
1241 </tr>
1242 <tr>
1243 <td>640 dpi (xxxhdpi)</td>
1244 <td>768MB</td>
1245 </tr>
1246</table>
1247
1248
1249<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1250
1251
1252<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1253
1254
1255<p>Android includes a launcher application (home screen) and support for
1256third-party applications to replace the device launcher (home screen). Device
1257implementations that allow third-party applications to replace the device home
1258screen MUST declare the platform feature android.software.home_screen.</p>
1259
1260<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1261
1262<div class="note">
1263<p>Widgets are optional for all Android device implementations, but SHOULD be
1264supported on Android Handheld devices.</p>
1265</div>
1266
1267
1268<p>Android defines a component type and corresponding API and lifecycle that
1269allows 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, 21</a>] a feature that is strongly RECOMMENDED to be supported on Handheld Device
1270implementations. Device implementations that support embedding widgets on the
1271home screen MUST meet the following requirements and declare support for
1272platform feature android.software.app_widgets.</p>
1273
1274<ul>
1275 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1276interface affordances to add, configure, view, and remove AppWidgets directly
1277within the Launcher.</li>
1278 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1279the standard grid size. See the App Widget Design Guidelines in the Android SDK
1280documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1281 <li>Device implementations that include support for lock screen MAY support
1282application widgets on the lock screen.</li>
1283</ul>
1284
1285<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1286
1287
1288<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, 22</a>], using hardware and software features of the device.</p>
1289
1290<p>Some APIs allow applications to perform notifications or attract attention
1291using hardware&#8212;specifically sound, vibration, and light. Device implementations
1292MUST support notifications that use hardware features, as described in the SDK
1293documentation, and to the extent possible with the device implementation
1294hardware. For instance, if a device implementation includes a vibrator, it MUST
1295correctly implement the vibration APIs. If a device implementation lacks
1296hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1297is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1298
1299<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1300etc.) provided for in the APIs
1301[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1302or in the Status/System Bar icon style guide
1303[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1304which in the case of an Android Television device includes the possibility to not display the
1305notifications. Device implementers MAY provide an alternative user experience for
1306notifications than that provided by the reference Android Open Source
1307implementation; however, such alternative notification systems MUST support
1308existing notification resources, as above. </p>
1309
1310<p>Android includes support for various notifications, such as:</p>
1311
1312<ul>
1313 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1314 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1315 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1316</ul>
1317
1318<p>Android device implementations, when such notifications are made visible, MUST properly execute
1319Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1320APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1321</p>
1322
1323<p>Android includes Notification Listener Service APIs that allow apps (once
1324explicitly enabled by the user) to receive a copy of all notifications as they
1325are posted or updated. Device implementations MUST correctly and promptly send
1326notifications in their entirety to all such installed and user-enabled listener
1327services, including any and all metadata attached to the Notification object.</p>
1328
1329<h3 id="3_8_4_search">3.8.4. Search</h3>
1330
1331
1332<p>Android includes APIs [<a href="http://developer.android.com/reference/android/app/SearchManager.html">Resources, 26</a>] that allow developers to incorporate search into their applications, and
1333expose their application&rsquo;s data into the global system search. Generally
1334speaking, this functionality consists of a single, system-wide user interface
1335that allows users to enter queries, displays suggestions as users type, and
1336displays results. The Android APIs allow developers to reuse this interface to
1337provide search within their own apps, and allow developers to supply results to
1338the common global search user interface.</p>
1339
1340<p>Android device implementations SHOULD include global search, a single, shared,
1341system-wide search user interface capable of real-time suggestions in response
1342to user input. Device implementations SHOULD implement the APIs that allow
1343developers to reuse this user interface to provide search within their own
1344applications. Device implementations that implement the global search interface
1345MUST implement the APIs that allow third-party applications to add suggestions
1346to the search box when it is run in global search mode. If no third-party
1347applications are installed that make use of this functionality, the default
1348behavior SHOULD be to display web search engine results and suggestions.</p>
1349
1350<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1351
1352
1353<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1354end user, that disappear after a brief period of time [<a href="http://developer.android.com/reference/android/widget/Toast.html">Resources, 27</a>]. Device implementations MUST display Toasts from applications to end users in
1355some high-visibility manner.</p>
1356
1357<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1358
1359
1360<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1361across an entire Activity or application.</p>
1362
1363<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1364application developers to use if they want to match the Holo theme look and
1365feel as defined by the Android SDK [<a href="http://developer.android.com/guide/topics/ui/themes.html">Resources, 28</a>]. Device implementations MUST NOT alter any of the Holo theme attributes
1366exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1367
1368<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1369application developers to use if they want to match the design theme&rsquo;s look and
1370feel across the wide variety of different Android device types. Device
1371implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1372of the Material theme attributes or their assets exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html#Theme_Material">Resources, 30</a>].</p>
1373
1374<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1375styles for application developers to use if they want to match the look and
1376feel of the device theme as defined by the device implementer. Device
1377implementations MAY modify the Device Default theme attributes exposed to
1378applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1379
Danielle Robertsbe0f08c2015-09-29 14:09:34 -0700[diff] [blame]1380<p>Android supports a variant theme with translucent system bars, which allows
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1381application developers to fill the area behind the status and navigation bar
1382with their app content. To enable a consistent developer experience in this
1383configuration, it is important the status bar icon style is maintained across
1384different device implementations. Therefore, Android device implementations
1385MUST use white for system status icons (such as signal strength and battery
1386level) and notifications issued by the system, unless the icon is indicating a
Danielle Robertsbe0f08c2015-09-29 14:09:34 -0700[diff] [blame]1387problematic status or an app requests a light status bar using the
1388SYSTEM_UI_FLAG_LIGHT_STATUS_BAR flag. When an app requests a light status bar,
1389Android device implementations MUST change the color of the system status icons
1390to black [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1391
1392<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1393
1394
1395<p>Android defines a component type and corresponding API and lifecycle that
1396allows 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, 31</a>]. Live wallpapers are animations, patterns, or similar images with limited
1397input capabilities that display as a wallpaper, behind other applications.</p>
1398
1399<p>Hardware is considered capable of reliably running live wallpapers if it can
1400run all live wallpapers, with no limitations on functionality, at a reasonable
1401frame rate with no adverse effects on other applications. If limitations in the
1402hardware cause wallpapers and/or applications to crash, malfunction, consume
1403excessive CPU or battery power, or run at unacceptably low frame rates, the
1404hardware is considered incapable of running live wallpaper. As an example, some
1405live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1406Live wallpaper will not run reliably on hardware that does not support multiple
1407OpenGL contexts because the live wallpaper use of an OpenGL context may
1408conflict with other applications that also use an OpenGL context.</p>
1409
1410<p>Device implementations capable of running live wallpapers reliably as described
1411above SHOULD implement live wallpapers, and when implemented MUST report the
1412platform feature flag android.software.live_wallpaper.</p>
1413
1414<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1415
1416<div class="note">
1417<p>As the Recent function navigation key is OPTIONAL, the requirements to
1418implement the overview screen is OPTIONAL for Android Television devices and
1419Android Watch devices.</p>
1420</div>
1421
1422
1423<p>The upstream Android source code includes the overview screen [<a href="http://developer.android.com/guide/components/recents.html">Resources, 32</a>], a system-level user interface for task switching and displaying recently
1424accessed activities and tasks using a thumbnail image of the application&rsquo;s
1425graphical state at the moment the user last left the application. Device
1426implementations 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>
1427
1428<ul>
1429 <li>MUST display affiliated recents as a group that moves together.</li>
1430 <li>MUST support at least up to 20 displayed activities.</li>
1431 <li>MUST at least display the title of 4 activities at a time.</li>
1432 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1433 <li>MUST implement the screen pinning behavior [<a href="http://developer.android.com/about/versions/android-5.0.html#ScreenPinning">Resources, 33</a>] and provide the user with a settings menu to toggle the feature.</li>
1434 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1435interacts with screens.</li>
1436</ul>
1437
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]1438<p>Device implementations are STRONGLY RECOMMENDED to use the upstream Android user
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1439interface (or a similar thumbnail-based interface) for the overview screen.</p>
1440
1441<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1442
1443
1444<p>Android includes support for Input Management and support for third-party input
1445method editors [<a href="http://developer.android.com/guide/topics/text/creating-input-method.html">Resources, 34</a>]. Device implementations that allow users to use third-party input methods on
1446the device MUST declare the platform feature android.software.input_methods and
1447support IME APIs as defined in the Android SDK documentation.</p>
1448
1449<p>Device implementations that declare the android.software.input_methods feature
1450MUST provide a user-accessible mechanism to add and configure third-party input
1451methods. Device implementations MUST display the settings interface in response
1452to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1453
1454<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1455
1456
1457<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1458Media Notification Template that allows media applications to integrate with
1459playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1460Device implementations that support a lock screen, unless an Android Automotive or Watch
1461implementation, MUST display the Lockscreen Notifications including the Media Notification
1462Template.</p>
1463
1464<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1465
1466
1467<p>Android includes support for interactive screensavers called Dreams [<a href="http://developer.android.com/reference/android/service/dreams/DreamService.html">Resources, 36</a>]. Dreams allows users to interact with applications when a device connected to
1468a power source is idle or docked in a desk dock. Android Watch devices MAY
1469implement Dreams, but other types of device implementations SHOULD include
1470support for Dreams and provide a settings option for users to configure Dreams
1471in response to the android.settings.DREAM_SETTINGS intent.</p>
1472
1473<h3 id="3_8_12_location">3.8.12. Location</h3>
1474
1475
1476<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1477location coordinates, location modes MUST be displayed in the Location menu
1478within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1479
1480<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1481
1482
1483<p>Android includes support for color emoji characters. When Android device
1484implementations include an IME, devices SHOULD provide an input method to the
1485user for the Emoji characters defined in Unicode 6.1 [<a href="http://www.unicode.org/versions/Unicode6.1.0/">Resources, 38</a>]. All devices MUST be capable of rendering these emoji characters in color glyph.</p>
1486
1487<p>Android includes support for Roboto 2 font with different
1488weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1489sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1490the languages available on the device and full Unicode 7.0 coverage of Latin,
1491Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1492all glyphs in the currency symbols block of Unicode 7.0.</p>
1493
1494<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1495
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1496<p>Android includes features that allow security-aware applications to perform
1497device administration functions at the system level, such as enforcing password
1498policies or performing remote wipe, through the Android Device Administration
1499API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1500Device implementations MUST provide an implementation of the DevicePolicyManager class
1501[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1502Device implementations that include support for PIN (numeric) or PASSWORD
1503(alphanumeric) based lock screens MUST support the full range of device
1504administration policies defined in the Android SDK documentation
1505[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1506and report the platform feature android.software.device_admin.</p>
1507
Andy Dyer-smith3d24bbe2015-09-11 15:35:23 +0100[diff] [blame]1508<h3 id="3_9_1_device_provisioning">3.9.1 Device Provisioning</h3>
1509<h4 id="3_9_1_1_device_owner_provisioning">3.9.1.1 Device owner provisioning</h4>
1510<p>If a device implementation declares the android.software.device_admin feature,
1511the out of box setup flow MUST make it possible to enroll a Device Policy
1512Controller (DPC) application as the Device Owner app
1513[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">
1514Resources, XX</a>]. Device implementations MAY have a preinstalled application
1515performing device administration functions but this application MUST NOT be set
1516as the Device Owner app without explicit consent or action from the user or the
1517administrator of the device.</p>
1518
1519<p>The device owner provisioning process (the flow initiated by
1520android.app.action.PROVISION_MANAGED_DEVICE
1521[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_DEVICE">
1522Resources, XX</a>]) user experience MUST align with the AOSP implementation</p>
1523
1524<p>If the device implementation reports android.hardware.nfc, it MUST have NFC
1525enabled, even during the out-of-box setup flow, in order to allow for NFC
1526provisioning of Device owners
1527<a href="https://source.android.com/devices/tech/admin/provision.html#device_owner_provisioning_via_nfc">[Resources, XX]</a>.
1528</p>
1529
1530<h4 id="3_9_1_2_managed_profile_provisioning">3.9.1.2 Managed profile provisioning</h4>
1531<p>If a device implementation declares the android.software.managed_users,
1532it MUST be possible to enroll a Device Policy Controller (DPC) application
1533as the owner of a new Managed Profile
1534[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isProfileOwnerApp(java.lang.String)">
1535Resources, XX</a>]</p>
1536
1537<p>The managed profile provisioning process (the flow initiated by
1538android.app.action.PROVISION_MANAGED_PROFILE
1539[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#ACTION_PROVISION_MANAGED_PROFILE">
1540Resources, XX</a>]) user experience MUST align with the AOSP implementation
1541</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1542
1543<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1544
1545
1546<p>Android provides an accessibility layer that helps users with disabilities to
1547navigate their devices more easily. In addition, Android provides platform APIs
1548that enable accessibility service implementations to receive callbacks for user
1549and system events and generate alternate feedback mechanisms, such as
1550text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1551
1552<p>Device implementations include the following requirements:</p>
1553
1554<ul>
1555<li>Android Automotive implementations SHOULD provide an implementation of the
1556Android accessibility framework consistent with the default Android
1557implementation.</li>
1558<li>Device implementations (Android Automotive excluded) MUST provide an
1559implementation of the Android accessibility framework consistent with the
1560default Android implementation.</li>
1561<li>Device implementations (Android Automotive excluded) MUST support
1562third-party accessibility service implementations through the
1563android.accessibilityservice APIs
1564[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1565<li>Device implementations (Android Automotive excluded) MUST generate
1566AccessibilityEvents and deliver these events to all registered
1567AccessibilityService implementations in a manner consistent with the default
1568Android implementation</li>
1569<li> Device implementations (Android Automotive and Android Watch devices with
1570no audio output excluded), MUST provide a user-accessible mechanism to enable
1571and disable accessibility services, and MUST display this interface in response
1572to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1573</ul>
1574
1575<p>Additionally, device implementations SHOULD provide an implementation of an
1576accessibility service on the device, and SHOULD provide a mechanism for users
1577to enable the accessibility service during device setup. An open source
1578implementation of an accessibility service is available from the Eyes Free
1579project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1580
1581<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1582
1583
1584<p>Android includes APIs that allow applications to make use of text-to-speech
1585(TTS) services and allows service providers to provide implementations of TTS
1586services [<a href="http://developer.android.com/reference/android/speech/tts/package-summary.html">Resources, 45</a>]. Device implementations reporting the feature android.hardware.audio.output
1587MUST meet these requirements related to the Android TTS framework. </p>
1588
1589<p>Android Automotive implementations:</p>
1590<ul>
1591<li>MUST support the Android TTS framework APIs.</li>
1592<li>MAY support installation of third-party TTS engines. If supported, partners
1593MUST provide a user-accessible interface that allows the user to select a TTS
1594engine for use at system level.</li>
1595</ul>
1596
1597<p>All other device implementations:</p>
1598
1599<ul>
1600 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1601supporting the languages available on the device. Note that the upstream
1602Android open source software includes a full-featured TTS engine
1603implementation.
1604 <li> MUST support installation of third-party TTS engines
1605 <li> MUST provide a user-accessible interface that allows users to select a TTS
1606engine for use at the system level
1607</ul>
1608
1609<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1610
1611
1612<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1613content to Android Television devices. TIF provides a standard API to create
1614input modules that control Android Television devices. Android Television
1615device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1616
1617<p>Device implementations that support TIF MUST declare the platform feature
1618android.software.live_tv.</p>
1619
1620<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1621
1622
1623<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1624by the &ldquo;aapt&rdquo; tool included in the official Android SDK [<a href="http://developer.android.com/tools/help/index.html">Resources, 47</a>].</p>
1625
1626<p>Devices implementations MUST NOT extend either the .apk [<a href="http://developer.android.com/guide/components/fundamentals.html">Resources, 48</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/+/lollipop-release/docs/">Resources, 20</a>], or RenderScript bytecode formats in such a way that would prevent those
1627files from installing and running correctly on other compatible devices.</p>
1628
1629<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1630
1631
1632<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1633
1634
1635<p>Device implementations MUST support the core media formats specified in the
1636Android SDK documentation [<a href="http://developer.android.com/guide/appendix/media-formats.html">Resources, 50</a>] except where explicitly permitted in this document. Specifically, device
1637implementations MUST support the media formats, encoders, decoders, file types,
1638and container formats defined in the tables below and reported via MediaCodecList
1639[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1640Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1641[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1642113</a>].
1643
1644All of these codecs are
1645provided as software implementations in the preferred Android implementation
1646from the Android Open Source Project.</p>
1647
1648<p>Please note that neither Google nor the Open Handset Alliance make any
1649representation that these codecs are free from third-party patents. Those
1650intending to use this source code in hardware or software products are advised
1651that implementations of this code, including in open source software or
1652shareware, may require patent licenses from the relevant patent holders.</p>
1653
1654<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1655
1656<table>
1657 <tr>
1658 <th>Format/Codec</th>
1659 <th>Encoder</th>
1660 <th>Decoder</th>
1661 <th>Details</th>
1662 <th>Supported File Types/Container Formats</th>
1663 </tr>
1664 <tr>
1665 <td>MPEG-4 AAC Profile</p>
1666
1667<p>(AAC LC)</td>
1668 <td>REQUIRED<sup>1</sup></td>
1669 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1670 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 8 to
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]167148 kHz.</td>
1672 <td>
1673 <ul>
1674 <li class="table_list">3GPP (.3gp)</li>
1675 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1676 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1677supported)</li>
1678 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1679 </tr>
1680 <tr>
1681 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1682 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1683 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1684 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 16
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1685to 48 kHz.</td>
1686 <td></td>
1687 </tr>
1688 <tr>
1689 <td>MPEG-4 HE AACv2</p>
1690
1691<p>Profile (enhanced AAC+)</td>
1692 <td> </td>
1693 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1694 <td>Support for mono/stereo/5.0/5.1<sup>2</sup> content with standard sampling rates from 16
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1695to 48 kHz.</td>
1696 <td></td>
1697 </tr>
1698 <tr>
1699 <td>AAC ELD (enhanced low delay AAC)</td>
1700 <td>REQUIRED<sup>1</sup> </p>
1701
1702<p>(Android 4.1+)</td>
1703 <td>REQUIRED</p>
1704
1705<p>(Android 4.1+)</td>
1706 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1707 <td></td>
1708 </tr>
1709 <tr>
1710 <td>AMR-NB</td>
1711 <td>REQUIRED<sup>3</sup></td>
1712 <td>REQUIRED<sup>3</sup></td>
1713 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1714 <td>3GPP (.3gp)</td>
1715 </tr>
1716 <tr>
1717 <td>AMR-WB</td>
1718 <td>REQUIRED<sup>3</sup></td>
1719 <td>REQUIRED<sup>3</sup></td>
1720 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1721 <td></td>
1722 </tr>
1723 <tr>
1724 <td>FLAC</td>
1725 <td></td>
1726 <td>REQUIRED <br>(Android 3.1+)</td>
1727 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]1728RECOMMENDED on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1729does not include a low-pass filter). 16-bit RECOMMENDED; no dither applied for
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]173024-bit.</td>
1731 <td>FLAC (.flac) only</td>
1732 </tr>
1733 <tr>
1734 <td>MP3</td>
1735 <td></td>
1736 <td>REQUIRED</td>
1737 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1738 <td>MP3 (.mp3)</td>
1739 </tr>
1740 <tr>
1741 <td>MIDI</td>
1742 <td></td>
1743 <td>REQUIRED</td>
1744 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1745ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1746 <td><ul>
1747 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1748 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1749 <li class="table_list">OTA (.ota)</li>
1750 <li class="table_list">iMelody (.imy)</li></ul></td>
1751 </tr>
1752 <tr>
1753 <td>Vorbis</td>
1754 <td></td>
1755 <td>REQUIRED</td>
1756 <td></td>
1757 <td><ul>
1758 <li class="table_list">Ogg (.ogg)</li>
1759 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1760 </tr>
1761 <tr>
1762 <td>PCM/WAVE</td>
1763 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1764 <td>REQUIRED</td>
1765 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1766sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1767frequencies.</td>
1768 <td>WAVE (.wav)</td>
1769 </tr>
1770 <tr>
1771 <td>Opus</td>
1772 <td></td>
1773 <td>REQUIRED<br> (Android 5.0+)</td>
1774 <td></td>
1775 <td>Matroska (.mkv)</td>
1776 </tr>
1777</table>
1778
1779
1780<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1781but optional for Android Watch device implementations.</p>
1782
1783<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17842 channels is optional.</p>
1785
1786<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1787
1788<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1789including Android Watch device implementations.</p>
1790
1791<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1792
1793<table>
1794 <tr>
1795 <th>Format/Codec</th>
1796 <th>Encoder</th>
1797 <th>Decoder</th>
1798 <th>Details</th>
1799 <th>Supported File Types/Container Formats</th>
1800 </tr>
1801 <tr>
1802 <td>JPEG</td>
1803 <td>REQUIRED</td>
1804 <td>REQUIRED</td>
1805 <td>Base+progressive</td>
1806 <td>JPEG (.jpg)</td>
1807 </tr>
1808 <tr>
1809 <td>GIF</td>
1810 <td></td>
1811 <td>REQUIRED</td>
1812 <td></td>
1813 <td>GIF (.gif)</td>
1814 </tr>
1815 <tr>
1816 <td>PNG</td>
1817 <td>REQUIRED</td>
1818 <td>REQUIRED</td>
1819 <td></td>
1820 <td>PNG (.png)</td>
1821 </tr>
1822 <tr>
1823 <td>BMP</td>
1824 <td></td>
1825 <td>REQUIRED</td>
1826 <td></td>
1827 <td>BMP (.bmp)</td>
1828 </tr>
1829 <tr>
1830 <td>WebP</td>
1831 <td>REQUIRED</td>
1832 <td>REQUIRED</td>
1833 <td></td>
1834 <td>WebP (.webp)</td>
1835 </tr>
1836</table>
1837
1838
1839<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1840
1841<p>Video codecs are optional for Android Watch device implementations.</p>
1842
1843<table>
1844 <tr>
1845 <th>Format/Codec</th>
1846 <th>Encoder</th>
1847 <th>Decoder</th>
1848 <th>Details</th>
1849 <th>Supported File Types/<br>Container Formats</th>
1850 </tr>
1851 <tr>
1852 <td>H.263</td>
1853 <td>REQUIRED<sup>1</sup></td>
1854 <td>REQUIRED<sup>2</sup></td>
1855 <td></td>
1856 <td><ul>
1857 <li class="table_list">3GPP (.3gp)</li>
1858 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1859 </tr>
1860 <tr>
1861 <td>H.264 AVC</td>
1862 <td>REQUIRED<sup>2</sup></td>
1863 <td>REQUIRED<sup>2</sup></td>
1864 <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>
1865 <td><ul>
1866 <li class="table_list">3GPP (.3gp)</li>
1867 <li class="table_list">MPEG-4 (.mp4)</li>
1868 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1869 </tr>
1870 <tr>
1871 <td>H.265 HEVC</td>
1872 <td></td>
1873 <td>REQUIRED<sup>5</sup></td>
1874 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1875 <td>MPEG-4 (.mp4)</td>
1876 </tr>
1877 <tr>
1878 <td>MPEG-4 SP</td>
1879 <td></td>
1880 <td>REQUIRED<sup>2</sup></td>
1881 <td></td>
1882 <td>3GPP (.3gp)</td>
1883 </tr>
1884 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1885 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1886 <td>REQUIRED<sup>2</sup></p>
1887
1888<p>(Android 4.3+)</td>
1889 <td>REQUIRED<sup>2</sup></p>
1890
1891<p>(Android 2.3.3+)</td>
1892 <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>
1893 <td><ul>
1894 <li class="table_list">WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 110</a></li>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1895 <li class="table_list">Matroska (.mkv, Android 4.0+)<sup>4</sup></li></ul></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1896 </tr>
1897 <tr>
1898 <td>VP9</td>
1899 <td></td>
1900 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1901 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1902 <td><ul>
1903 <li class="table_list">WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 110</a>]</li>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1904 <li class="table_list">Matroska (.mkv, Android 4.0+)<sup>4</sup></li></ul></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1905 </tr>
1906</table>
1907
1908
1909<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1910android.hardware.camera or android.hardware.camera.front.</p>
1911
1912<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1913
1914<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1915device implementations SHOULD use a hardware VP8 codec that meets the
1916requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1917
1918<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1919
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]1920<p class="table_footnote">5 STRONGLY RECOMMENDED for Android Automotive, optional for Android Watch, and required for all other device types.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1921
1922<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1923
1924<div class="note">
1925<p>Video codecs are optional for Android Watch device implementations.</p>
1926</div>
1927
1928
1929<p>Android device implementations with H.264 codec support, MUST support Baseline
1930Profile Level 3 and the following SD (Standard Definition) video encoding
1931profiles and SHOULD support Main Profile Level 4 and the following HD (High
1932Definition) video encoding profiles. Android Television devices are STRONGLY
1933RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1934<table>
1935 <tr>
1936 <th></th>
1937 <th>SD (Low quality)</th>
1938 <th>SD (High quality)</th>
1939 <th>HD 720p1</th>
1940 <th>HD 1080p1</th>
1941 </tr>
1942 <tr>
1943 <th>Video resolution</th>
1944 <td>320 x 240 px</td>
1945 <td>720 x 480 px</td>
1946 <td>1280 x 720 px</td>
1947 <td>1920 x 1080 px</td>
1948 </tr>
1949 <tr>
1950 <th>Video frame rate</th>
1951 <td>20 fps</td>
1952 <td>30 fps</td>
1953 <td>30 fps</td>
1954 <td>30 fps</td>
1955 </tr>
1956 <tr>
1957 <th>Video bitrate</th>
1958 <td>384 Kbps</td>
1959 <td>2 Mbps</td>
1960 <td>4 Mbps</td>
1961 <td>10 Mbps</td>
1962 </tr>
1963</table>
1964
1965
1966<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1967devices.</p>
1968
1969<p>Android device implementations with VP8 codec support MUST support the SD video
1970encoding profiles and SHOULD support the following HD (High Definition) video
1971encoding profiles.</p>
1972<table>
1973 <tr>
1974 <th></th>
1975 <th>SD (Low quality)</th>
1976 <th>SD (High quality)</th>
1977 <th>HD 720p1</th>
1978 <th>HD 1080p1</th>
1979 </tr>
1980 <tr>
1981 <th>Video resolution</th>
1982 <td>320 x 180 px</td>
1983 <td>640 x 360 px</td>
1984 <td>1280 x 720 px</td>
1985 <td>1920 x 1080 px</td>
1986 </tr>
1987 <tr>
1988 <th>Video frame rate</th>
1989 <td>30 fps</td>
1990 <td>30 fps</td>
1991 <td>30 fps</td>
1992 <td>30 fps</td>
1993 </tr>
1994 <tr>
1995 <th>Video bitrate</th>
1996 <td>800 Kbps </td>
1997 <td>2 Mbps</td>
1998 <td>4 Mbps</td>
1999 <td>10 Mbps</td>
2000 </tr>
2001</table>
2002
2003<p class="table_footnote">1 When supported by hardware.</p>
2004
2005<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
2006
2007<div class="note">
2008<p>Video codecs are optional for Android Watch device implementations.</p>
2009</div>
2010
2011
2012<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2013the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
2014standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2015
2016<p>Android device implementations with H.264 decoders, MUST support Baseline
2017Profile Level 3 and the following SD video decoding profiles and SHOULD support
2018the HD decoding profiles. Android Television devices MUST support High Profile
2019Level 4.2 and the HD 1080p decoding profile.</p>
2020<table>
2021 <tr>
2022 <th></th>
2023 <th>SD (Low quality)</th>
2024 <th>SD (High quality)</th>
2025 <th>HD 720p1</th>
2026 <th>HD 1080p1</th>
2027 </tr>
2028 <tr>
2029 <th>Video resolution</th>
2030 <td>320 x 240 px</td>
2031 <td>720 x 480 px</td>
2032 <td>1280 x 720 px</td>
2033 <td>1920 x 1080 px</td>
2034 </tr>
2035 <tr>
2036 <th>Video frame rate</th>
2037 <td>30 fps</td>
2038 <td>30 fps</td>
2039 <td>30 fps / 60 fps2</td>
2040 <td>30 fps / 60 fps2</td>
2041 </tr>
2042 <tr>
2043 <th>Video bitrate</th>
2044 <td>800 Kbps </td>
2045 <td>2 Mbps</td>
2046 <td>8 Mbps</td>
2047 <td>20 Mbps</td>
2048 </tr>
2049</table>
2050
2051
2052<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2053types only when supported by hardware.</p>
2054
2055<p class="table_footnote">2 Required for Android Television device implementations.</p>
2056
2057<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
2058decoding profiles. Android Television devices MUST support the HD 1080p
2059decoding profile. </p>
2060<table>
2061 <tr>
2062 <th></th>
2063 <th>SD (Low quality)</th>
2064 <th>SD (High quality)</th>
2065 <th>HD 720p1</th>
2066 <th>HD 1080p1</th>
2067 </tr>
2068 <tr>
2069 <th>Video resolution</th>
2070 <td>320 x 180 px</td>
2071 <td>640 x 360 px</td>
2072 <td>1280 x 720 px</td>
2073 <td>1920 x 1080 px</td>
2074 </tr>
2075 <tr>
2076 <th>Video frame rate</th>
2077 <td>30 fps</td>
2078 <td>30 fps</td>
2079 <td>30 fps / 60 fps2</td>
2080 <td>30 / 60 fps2</td>
2081 </tr>
2082 <tr>
2083 <th>Video bitrate</th>
2084 <td>800 Kbps </td>
2085 <td>2 Mbps</td>
2086 <td>8 Mbps</td>
2087 <td>20 Mbps</td>
2088 </tr>
2089</table>
2090
2091
2092<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2093devices only when supported by hardware.</p>
2094
2095<p class="table_footnote">2 Required for Android Television device implementations.</p>
2096
2097<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
2098HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2099support the HD 1080p decoding profile and SHOULD support the UHD decoding
2100profile. When the UHD video decoding profile is supported, it MUST support 8
2101bit color depth.</p>
2102<table>
2103 <tr>
2104 <th></th>
2105 <th>SD (Low quality)</th>
2106 <th>SD (High quality)</th>
2107 <th>HD 720p 1</th>
2108 <th>HD 1080p 2</th>
2109 <th>UHD 2</th>
2110 </tr>
2111 <tr>
2112 <th>Video resolution</th>
2113 <td>320 x 180 px</td>
2114 <td>640 x 360 px</td>
2115 <td>1280 x 720 px</td>
2116 <td>1920 x 1080 px</td>
2117 <td>3840 x 2160 px</td>
2118 </tr>
2119 <tr>
2120 <th>Video frame rate</th>
2121 <td>30 fps</td>
2122 <td>30 fps</td>
2123 <td>30 fps</td>
2124 <td>30 fps</td>
2125 <td>30 fps</td>
2126 </tr>
2127 <tr>
2128 <th>Video bitrate</th>
2129 <td>600 Kbps </td>
2130 <td>1.6 Mbps</td>
2131 <td>4 Mbps</td>
2132 <td>10 Mbps</td>
2133 <td>20 Mbps</td>
2134 </tr>
2135</table>
2136
2137
2138<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2139devices only when supported by hardware.</p>
2140
2141<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2142supported by hardware.</p>
2143
2144<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
2145decoding profiles and SHOULD support the HD decoding profiles. Android
2146Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21471080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2148the UHD decoding profile.</p>
2149<table>
2150 <tr>
2151 <th></th>
2152 <th>SD (Low quality)</th>
2153 <th>SD (High quality)</th>
2154 <th>HD 720p </strong>1 </td>
2155 <th>HD 1080p </strong>1 </td>
2156 <th>UHD </strong>2</td>
2157 </tr>
2158 <tr>
2159 <th>Video resolution</th>
2160 <td>352 x 288 px</td>
2161 <td>640 x 360 px</td>
2162 <td>1280 x 720 px</td>
2163 <td>1920 x 1080 px</td>
2164 <td>3840 x 2160 px</td>
2165 </tr>
2166 <tr>
2167 <th>Video frame rate</th>
2168 <td>30 fps</td>
2169 <td>30 fps</td>
2170 <td>30 fps</td>
2171 <td>30 fps</td>
2172 <td>30 fps</td>
2173 </tr>
2174 <tr>
2175 <th>Video bitrate</th>
2176 <td>600 Kbps </td>
2177 <td>1.6 Mbps</td>
2178 <td>4 Mbps</td>
2179 <td>10 Mbps</td>
2180 <td>20 Mbps</td>
2181 </tr>
2182</table>
2183
2184
2185<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2186devices only when supported by hardware.</p>
2187
2188<p class="table_footnote">2 Required for Android Television device implementations when supported by
2189hardware.</p>
2190
2191<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2192
2193
2194<p>While some of the requirements outlined in this section are stated as SHOULD
2195since Android 4.3, the Compatibility Definition for a future version is planned
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]2196to change these to MUST. Existing and new Android devices are <strong>STRONGLY RECOMMENDED</strong> to meet these requirements, or they will not be able to attain Android
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2197compatibility when upgraded to the future version.</p>
2198
2199<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2200
2201
2202<p>Device implementations that declare android.hardware.microphone MUST allow
2203capture of raw audio content with the following characteristics:</p>
2204
2205<ul>
2206 <li><strong>Format</strong>: Linear PCM, 16-bit
2207 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2208 <li><strong>Channels</strong>: Mono
2209</ul>
2210
2211<p>Device implementations that declare android.hardware.microphone SHOULD allow
2212capture of raw audio content with the following characteristics:</p>
2213
2214<ul>
2215 <li><strong>Format</strong>: Linear PCM, 16-bit
2216 <li><strong>Sampling rates</strong>: 22050, 48000
2217 <li><strong>Channels</strong>: Stereo
2218</ul>
2219
2220<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2221
2222
2223<p>In addition to the above recording specifications, when an application has
2224started recording an audio stream using the
2225android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2226
2227<ul>
2228 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2229characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2230 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2231source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2232 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2233dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2234 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2235level at the microphone.
2236 <li>Noise reduction processing, if present, MUST be disabled.
2237 <li>Automatic gain control, if present, MUST be disabled
2238</ul>
2239
2240<p>If the platform supports noise suppression technologies tuned for speech
2241recognition, the effect MUST be controllable from the
2242android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2243noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2244of the noise suppression technology.</p>
2245
2246<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2247
2248
2249<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2250audio source. Devices that declare android.hardware.audio.output MUST properly
2251implement the REMOTE_SUBMIX audio source so that when an application uses the
2252android.media.AudioRecord API to record from this audio source, it can capture
2253a mix of all audio streams except for the following:</p>
2254
2255<ul>
2256 <li>STREAM_RING
2257 <li>STREAM_ALARM
2258 <li>STREAM_NOTIFICATION
2259</ul>
2260
2261<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2262
2263
2264<p>Device implementations that declare android.hardware.audio.output MUST conform
2265to the requirements in this section.</p>
2266
2267<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2268
2269
2270<p>The device MUST allow playback of raw audio content with the following
2271characteristics:</p>
2272
2273<ul>
2274 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2275 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2276 <li><strong>Channels</strong>: Mono, Stereo</li>
2277</ul>
2278
2279<p>The device SHOULD allow playback of raw audio content with the following
2280characteristics:</p>
2281
2282<ul>
2283 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2284</ul>
2285
2286<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2287
2288
2289<p>Android provides an API for audio effects for device implementations [<a href="http://developer.android.com/reference/android/media/audiofx/AudioEffect.html">Resources, 52</a>]. Device implementations that declare the feature
2290android.hardware.audio.output:</p>
2291
2292<ul>
2293 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2294implementations controllable through the AudioEffect subclasses Equalizer,
2295LoudnessEnhancer.</li>
2296 <li>MUST support the visualizer API implementation, controllable through the
2297Visualizer class.</li>
2298 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2299EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2300controllable through the AudioEffect sub-classes BassBoost,
2301EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2302</ul>
2303
2304<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2305
2306
2307<p>Android Television device implementations MUST include support for system
2308Master Volume and digital audio output volume attenuation on supported outputs,
2309except for compressed audio passthrough output (where no audio decoding is done
2310on the device).</p>
2311
2312<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2313
2314
2315<p>Audio latency is the time delay as an audio signal passes through a system.
2316Many classes of applications rely on short latencies, to achieve real-time
2317sound effects.</p>
2318
2319<p>For the purposes of this section, use the following definitions:</p>
2320
2321<ul>
2322 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2323when the corresponding sound can be heard by an external listener or observed
2324by a transducer.</li>
2325 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2326idle and powered down prior to the request.</li>
2327 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2328 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2329when an application reads the corresponding frame of PCM-coded data.</li>
2330 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2331audio input system has been idle and powered down prior to the request.</li>
2332 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2333 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2334 <li><strong>cold input jitter</strong>. The variance among separate measurements of cold input latency values.</li>
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2335 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2336 one buffer period.
2337 The buffer period term allows processing time for the app and for the app to
2338 mitigate phase difference between input and output streams.
2339 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2340 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2341NDK_root/docs/opensles/index.html.</li>
2342</ul>
2343
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]2344<p>Device implementations that declare android.hardware.audio.output are STRONGLY RECOMMENDED to meet
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2345or exceed these audio output requirements:</p>
2346
2347<ul>
2348 <li>cold output latency of 100 milliseconds or less</li>
2349 <li>continuous output latency of 45 milliseconds or less</li>
2350 <li>minimize the cold output jitter</li>
2351</ul>
2352
2353<p>If a device implementation meets the requirements of this section after any
2354initial calibration when using the OpenSL ES PCM buffer queue API, for
2355continuous output latency and cold output latency over at least one supported
2356audio output device, it MAY report support for low-latency audio, by reporting
2357the feature android.hardware.audio.low_latency via the
2358android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>]. Conversely, if the device implementation does not meet these requirements it
2359MUST NOT report support for low-latency audio.</p>
2360
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]2361<p>Device implementations that include android.hardware.microphone are STRONGLY RECOMMENDED to meet
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2362these input audio requirements:</p>
2363
2364<ul>
2365 <li>cold input latency of 100 milliseconds or less</li>
2366 <li>continuous input latency of 30 milliseconds or less</li>
2367 <li>continuous round-trip latency of 50 milliseconds or less</li>
2368 <li>minimize the cold input jitter</li>
2369</ul>
2370
2371<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2372
2373
2374<p>Devices MUST support the media network protocols for audio and video playback
2375as specified in the Android SDK documentation [<a href="http://developer.android.com/guide/appendix/media-formats.html">Resources, 50</a>]. Specifically, devices MUST support the following media network protocols:</p>
2376
2377<ul>
2378 <li>RTSP (RTP, SDP)</li>
2379 <li>HTTP(S) progressive streaming</li>
2380 <li>HTTP(S) Live Streaming draft protocol, Version 3 [<a href="http://tools.ietf.org/html/draft-pantos-http-live-streaming-03">Resources, 54</a>]</li>
2381</ul>
2382
2383<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2384
2385
2386<p>Device implementations that support secure video output and are capable of
2387supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2388implementations that declare support for Display.FLAG_SECURE, if they support a
2389wireless display protocol, MUST secure the link with a cryptographically strong
2390mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2391if they support a wired external display, the device implementations MUST
2392support HDCP 1.2 or higher. Android Television device implementations MUST
2393support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2394lower resolutions. The upstream Android open source implementation includes
2395support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2396requirement.</p>
2397
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2398<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2399
2400<p>
2401If a device implementation supports the inter-app MIDI software transport
2402(virtual MIDI devices), and it supports MIDI over
2403<em>all</em> of the following MIDI-capable hardware transports
2404for which it provides generic non-MIDI connectivity, it MAY report
2405support for feature android.software.midi via the
2406android.content.pm.PackageManager class
2407[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2408</p>
2409
2410<p>The MIDI-capable hardware transports are:</p>
2411<ul>
2412 <li>USB host mode (section 7.7 USB)</li>
2413 <li>USB peripheral mode (section 7.7 USB)</li>
2414</ul>
2415
2416<p>
2417Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2418MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2419it MUST NOT report support for feature android.software.midi.
2420</p>
2421
2422<p>
2423MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2424is in trial use status. A device implementation that reports
2425feature android.software.midi, and which provides generic non-MIDI connectivity
2426over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2427</p>
2428
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2429<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2430
2431<p>
2432If a device implementation meets <em>all</em> of the following requirements,
2433it MAY report support for feature android.hardware.audio.pro via the
2434android.content.pm.PackageManager class
2435[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2436</p>
2437
2438<ul>
2439
2440<li>
Glenn Kasten1578ece2015-09-15 13:44:17 -0700[diff] [blame]2441The device implementation MUST report support for feature android.hardware.audio.low_latency.
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2442</li>
2443
2444<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2445MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2446supported path.
2447</li>
2448
2449<li>
Glenn Kasten1578ece2015-09-15 13:44:17 -0700[diff] [blame]2450If the device includes a 4 conductor 3.5mm audio jack,
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2451the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2452and SHOULD be 10 milliseconds or less over at the audio jack path.
2453</li>
2454
2455<li>
2456The device implementation MUST include a USB port(s) supporting USB host mode and
2457USB peripheral mode.
2458</li>
2459
2460<li>
Glenn Kasten755f4b22015-09-25 16:04:23 -0700[diff] [blame]2461The USB host mode MUST implement the USB audio class.
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2462</li>
2463
2464<li>
2465If the device includes an HDMI port, the device implementation
Glenn Kasten1578ece2015-09-15 13:44:17 -0700[diff] [blame]2466MUST support output in stereo and eight channels
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2467at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2468</li>
2469
2470<li>
2471The device implementation MUST report support for feature android.software.midi.
2472</li>
2473
Glenn Kasten1578ece2015-09-15 13:44:17 -0700[diff] [blame]2474<li>
2475If the device includes a 4 conductor 3.5mm audio jack,
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]2476the device implementation is STRONGLY RECOMMENDED to comply with section
Glenn Kasten1578ece2015-09-15 13:44:17 -0700[diff] [blame]2477<a href="https://source.android.com/accessories/headset/specification.html#mobile_device_jack_specifications">Mobile device (jack) specifications</a>
2478of the
2479<a href="https://source.android.com/accessories/headset/specification.html">Wired Audio Headset Specification (v1.1)</a>.
2480</li>
2481
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2482</ul>
2483
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2484<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2485
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2486<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2487
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2488<p>Device implementations MUST support the Android Developer Tools provided in the
2489Android SDK. Android compatible devices MUST be compatible with:</p>
2490
2491<ul>
2492 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2493</ul>
2494
2495<p>Device implementations MUST support all adb functions as documented in the
2496Android SDK including dumpsys [<a href="https://source.android.com/devices/input/diagnostics.html">Resources, 56</a>]. The device-side adb daemon MUST be inactive by default and there MUST be a
2497user-accessible mechanism to turn on the Android Debug Bridge. If a device
2498implementation omits USB peripheral mode, it MUST implement the Android Debug
2499Bridge via local-area network (such as Ethernet or 802.11). </p>
2500
2501<p>Android includes support for secure adb. Secure adb enables adb on known
2502authenticated hosts. Device implementations MUST support secure adb.</p>
2503
2504<ul>
2505 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2506</ul>
2507
2508<p>Device implementations MUST support all ddms features as documented in the
2509Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2510but MUST be supported whenever the user has activated the Android Debug Bridge,
2511as above.</p>
2512
2513<ul>
2514 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2515</ul>
2516
2517<p>Device implementations MUST include the Monkey framework, and make it available
2518for applications to use.</p>
2519
2520<ul>
2521 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2522</ul>
2523
2524<p>Device implementations MUST support systrace tool as documented in the Android
2525SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2526mechanism to turn on Systrace.</p>
2527
2528<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2529using the standard Android SDK tools, without additional support; however
2530Microsoft Windows systems typically require a driver for new Android devices.
2531(For instance, new vendor IDs and sometimes new device IDs require custom USB
2532drivers for Windows systems.) If a device implementation is unrecognized by the
2533adb tool as provided in the standard Android SDK, device implementers MUST
2534provide Windows drivers allowing developers to connect to the device using the
2535adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
Unsuk Jung5ad5aba2015-09-29 22:13:02 -0700[diff] [blame]2536Windows 7, Windows 8 and Windows 10 in both 32-bit and 64-bit versions.
2537</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2538
2539<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2540
2541
2542<p>Android includes support for developers to configure application
2543development-related settings. Device implementations MUST honor the
2544android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2545development-related settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_APPLICATION_DEVELOPMENT_SETTINGS">Resources, 60</a>]. The upstream Android implementation hides the Developer Options menu by
2546default and enables users to launch Developer Options after pressing seven (7)
2547times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2548Developer Options. Specifically, device implementations MUST hide Developer
2549Options by default and MUST provide a mechanism to enable Developer Options
2550that is consistent with the upstream Android implementation.</p>
2551
2552<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2553
2554
2555<p>If a device includes a particular hardware component that has a corresponding
2556API for third-party developers, the device implementation MUST implement that
2557API as described in the Android SDK documentation. If an API in the SDK
2558interacts with a hardware component that is stated to be optional and the
2559device implementation does not possess that component:</p>
2560
2561<ul>
2562 <li>Complete class definitions (as documented by the SDK) for the component APIs
2563MUST still be presented.
2564 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2565 <li>API methods MUST return null values where permitted by the SDK documentation.
2566 <li>API methods MUST return no-op implementations of classes where null values are
2567not permitted by the SDK documentation.
2568 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2569</ul>
2570
2571<p>A typical example of a scenario where these requirements apply is the telephony
2572API: even on non-phone devices, these APIs must be implemented as reasonable
2573no-ops.</p>
2574
2575<p>Device implementations MUST consistently report accurate hardware configuration
2576information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2577methods on the android.content.pm.PackageManager class for the same build
2578fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2579
2580<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2581
2582
2583<p>Android includes facilities that automatically adjust application assets and UI
2584layouts appropriately for the device, to ensure that third-party applications
2585run well on a variety of hardware configurations [<a href="http://developer.android.com/guide/practices/screens_support.html">Resources, 61</a>]. Devices MUST properly implement these APIs and behaviors, as detailed in
2586this section.</p>
2587
2588<p>The units referenced by the requirements in this section are defined as
2589follows:</p>
2590
2591<ul>
2592 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2593of the display.</li>
2594 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
25951&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2596within the range.</li>
2597 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2598 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2599 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2600 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2601dps * (density/160).</li>
2602</ul>
2603
2604<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2605
2606
2607<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2608
2609<div class="note">
2610<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>
2611</div>
2612
2613<p>The Android UI framework supports a variety of different screen sizes, and
2614allows applications to query the device screen size (aka &ldquo;screen layout") via
2615android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2616Device implementations MUST report the correct screen size as defined in the
2617Android SDK documentation [<a href="http://developer.android.com/guide/practices/screens_support.html">Resources, 61</a>] and determined by the upstream Android platform. Specifically, device
2618implementations MUST report the correct screen size according to the following
2619logical density-independent pixel (dp) screen dimensions.</p>
2620
2621<ul>
2622 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2623is an Android Watch device.</li>
2624 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2625dp x 320 dp.</li>
2626 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2627dp x 480 dp.</li>
2628 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2629dp x 720 dp.</li>
2630</ul>
2631
2632<p>In addition, </p>
2633
2634<ul>
2635 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2636range from 1.1 to 2.5 inches.</li>
2637 <li>Other types of Android device implementations, with a physically integrated
2638screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2639</ul>
2640
2641<p>Devices MUST NOT change their reported screen size at any time.</p>
2642
2643<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2644&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2645implementations MUST correctly honor applications' stated support for small,
2646normal, large, and xlarge screens, as described in the Android SDK
2647documentation.</p>
2648
2649<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2650
2651<div class="note">
2652<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2653</div>
2654
2655
2656<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
265716:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2658such a device implementation will use a UI_MODE_TYPE_WATCH as the
2659android.content.res.Configuration.uiMode.</p>
2660
2661<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2662
2663
2664<p>The Android UI framework defines a set of standard logical densities to help
2665application developers target application resources. Device implementations
2666MUST report only one of the following logical Android framework densities
2667through the android.util.DisplayMetrics APIs, and MUST execute applications at
2668this standard density and MUST NOT change the value at at any time for the
2669default display.</p>
2670
2671<ul>
2672 <li>120 dpi (ldpi)</li>
2673 <li>160 dpi (mdpi)</li>
2674 <li>213 dpi (tvdpi)</li>
2675 <li>240 dpi (hdpi)</li>
2676 <li>280 dpi (280dpi)</li>
2677 <li>320 dpi (xhdpi)</li>
2678 <li>400 dpi (400dpi)</li>
2679 <li>480 dpi (xxhdpi)</li>
2680 <li>560 dpi (560dpi)</li>
2681 <li>640 dpi (xxxhdpi)</li>
2682</ul>
2683
2684<p>Device implementations SHOULD define the standard Android framework density
2685that is numerically closest to the physical density of the screen, unless that
2686logical density pushes the reported screen size below the minimum supported. If
2687the standard Android framework density that is numerically closest to the
2688physical density results in a screen size that is smaller than the smallest
2689supported compatible screen size (320 dp width), device implementations SHOULD
2690report the next lowest standard Android framework density.</p>
2691
2692<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2693
2694
2695<p>Device implementations MUST report correct values for all display metrics
2696defined in android.util.DisplayMetrics [<a href="http://developer.android.com/reference/android/util/DisplayMetrics.html">Resources, 62</a>] and MUST report the same values regardless of whether the embedded or
2697external screen is used as the default display.</p>
2698
2699<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2700
2701
2702<p>Devices MUST report which screen orientations they support
2703(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2704MUST report at least one supported orientation. For example, a device with a
2705fixed orientation landscape screen, such as a television or laptop, SHOULD only
2706report android.hardware.screen.landscape.</p>
2707
2708<p>Devices that report both screen orientations MUST support dynamic orientation
2709by applications to either portrait or landscape screen orientation. That is,
2710the device must respect the application&rsquo;s request for a specific screen
2711orientation. Device implementations MAY select either portrait or landscape
2712orientation as the default.</p>
2713
2714<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2715whenever queried via the android.content.res.Configuration.orientation,
2716android.view.Display.getOrientation(), or other APIs.</p>
2717
2718<p>Devices MUST NOT change the reported screen size or density when changing
2719orientation.</p>
2720
2721<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2722
2723
2724<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2725detailed in the Android SDK documentations. Device implementations SHOULD
2726support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2727implementations MUST also support Android RenderScript, as detailed in the
2728Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2729
2730<p>Device implementations MUST also correctly identify themselves as supporting
2731OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2732
2733<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2734 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2735for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2736 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2737libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2738ES 2.0.</li>
2739 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2740support the corresponding managed APIs and include support for native C/C++
2741APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2742libGLESv2.so MUST export the corresponding function symbols in addition to the
2743OpenGL ES 2.0 function symbols.</li>
2744</ul>
2745
2746<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2747interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2748and the ASTC texture compression format. Android device implementations MAY
2749support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2750support through the android.hardware.opengles.aep feature flag.</p>
2751
2752<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2753However, device implementations MUST report via the OpenGL ES managed and
2754native APIs all extension strings that they do support, and conversely MUST NOT
2755report extension strings that they do not support.</p>
2756
2757<p>Note that Android includes support for applications to optionally specify that
2758they require specific OpenGL texture compression formats. These formats are
2759typically vendor-specific. Device implementations are not required by Android
2760to implement any specific texture compression format. However, they SHOULD
2761accurately report any texture compression formats that they do support, via the
2762getString() method in the OpenGL API.</p>
2763
2764<p>Android includes a mechanism for applications to declare that they want to
2765enable hardware acceleration for 2D graphics at the Application, Activity,
2766Window, or View level through the use of a manifest tag
2767android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2768
2769<p>Device implementations MUST enable hardware acceleration by default, and MUST
2770disable hardware acceleration if the developer so requests by setting
2771android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2772through the Android View APIs.</p>
2773
2774<p>In addition, device implementations MUST exhibit behavior consistent with the
2775Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2776
2777<p>Android includes a TextureView object that lets developers directly integrate
2778hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2779Device implementations MUST support the TextureView API, and MUST exhibit
2780consistent behavior with the upstream Android implementation.</p>
2781
2782<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2783that indicates whether the EGLConfig supports rendering to an ANativeWindow
2784that records images to a video. Device implementations MUST support
2785EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2786
2787<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2788
2789
2790<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2791'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2792applications not developed for old versions of Android that pre-date
2793screen-size independence.</p>
2794
2795<ul>
2796<li>Android Automotive does not support legacy compatibility mode.</li>
2797<li>All other device implementations MUST include support for legacy application
2798compatibility mode as implemented by the upstream Android open source code. That
2799is, device implementations MUST NOT alter the triggers or thresholds at which
2800compatibility mode is activated, and MUST NOT alter the behavior of the
2801compatibility mode itself.</li>
2802</ul>
2803
2804<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2805
2806
2807<p>The Android platform includes APIs that allow applications to render rich
2808graphics to the display. Devices MUST support all of these APIs as defined by
2809the Android SDK unless specifically allowed in this document. </p>
2810
2811<ul>
2812 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2813SHOULD support displays capable of 24-bit color graphics.</li>
2814 <li>Devices MUST support displays capable of rendering animations.</li>
2815 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2816and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
281715% tolerance.</li>
2818</ul>
2819
2820<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2821
2822
2823<p>Android includes support for secondary display to enable media sharing
2824capabilities and developer APIs for accessing external displays. If a device
2825supports an external display either via a wired, wireless, or an embedded
2826additional display connection then the device implementation MUST implement the
2827display manager API as described in the Android SDK documentation [<a href="http://developer.android.com/reference/android/hardware/display/DisplayManager.html">Resources, 67</a>].</p>
2828
2829<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2830
2831<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2832for non-touch navigation.</p>
2833
2834<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2835
2836<div class="note">
2837<p>Android Watch and Android Automotive implementations MAY implement a soft
2838keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2839</div>
2840
2841
2842<p>Device implementations:</p>
2843
2844<ul>
2845 <li>MUST include support for the Input Management Framework (which allows
2846third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2847detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2848 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2849hard keyboard is present) except for Android Watch devices where the screen
2850size makes it less reasonable to have a soft keyboard.</li>
2851 <li>MAY include additional soft keyboard implementations.</li>
2852 <li>MAY include a hardware keyboard.</li>
2853 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2854specified in android.content.res.Configuration.keyboard [<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>] (QWERTY or 12-key).</li>
2855</ul>
2856
2857<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2858
2859<div class="note">
2860<p>Android Television devices MUST support D-pad.</p>
2861</div>
2862
2863<p>Device implementations:</p>
2864
2865<ul>
2866 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2867device implementation is not an Android Television device.</li>
2868 <li>MUST report the correct value for android.content.res.Configuration.navigation
2869[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2870 <li>MUST provide a reasonable alternative user interface mechanism for the
2871selection and editing of text, compatible with Input Management Engines. The
2872upstream Android open source implementation includes a selection mechanism
2873suitable for use with devices that lack non-touch navigation inputs.</li>
2874</ul>
2875
2876<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2877
2878<div class="note">
2879<p>The availability and visibility requirement of the Home, Recents, and Back
2880functions differ between device types as described in this section.</p>
2881</div>
2882
2883<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2884KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2885navigation paradigm and therefore:</p>
2886
2887<ul>
2888 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2889Back functions.</li>
2890 <li>Android Television device implementations MUST provide the Home and Back
2891functions.</li>
2892 <li>Android Watch device implementations MUST have the Home function available to
2893the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2894 <li>Android Automotive implementations MUST provide the Home function and MAY
2895provide Back and Recent functions.</li>
2896 <li>All other types of device implementations MUST provide the Home and Back
2897functions.</li>
2898</ul>
2899
2900<p>These functions MAY be implemented via dedicated physical buttons (such as
2901mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2902software keys on a distinct portion of the screen, gestures, touch panel, etc.
2903Android supports both implementations. All of these functions MUST be
2904accessible with a single action (e.g. tap, double-click or gesture) when
2905visible.</p>
2906
2907<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2908together with other navigation functions in full-screen mode. This does not
2909apply to devices upgrading from earlier Android versions that have physical
2910buttons for navigation and no recents key.</p>
2911
2912<p> The Home and Back functions, if provided, MUST each have a visible button or
2913icon unless hidden together with other navigation functions in full-screen mode
2914or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2915
2916<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2917Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2918implement a dedicated physical button for the Menu function. Older device
2919implementations SHOULD NOT implement a dedicated physical button for the Menu
2920function, but if the physical Menu button is implemented and the device is
2921running applications with targetSdkVersion > 10, the device implementation:</p>
2922
2923<ul>
2924 <li>MUST display the action overflow button on the action bar when it is visible
2925and the resulting action overflow menu popup is not empty. For a device
2926implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2927is RECOMMENDED.</li>
2928 <li>MUST NOT modify the position of the action overflow popup displayed by
2929selecting the overflow button in the action bar.</li>
2930 <li>MAY render the action overflow popup at a modified position on the screen when
2931it is displayed by selecting the physical menu button.</li>
2932</ul>
2933
2934<p>For backwards compatibility, device implementations MUST make the Menu function
2935available to applications when targetSdkVersion is less than 10, either by a physical
2936button, a software key, or gestures. This Menu function should be presented
2937unless hidden together with other navigation functions.</p>
2938
2939<p>Android supports Assist action [<a href="http://developer.android.com/reference/android/content/Intent.html#ACTION_ASSIST">Resources, 69</a>]. Android device implementations except for Android Watch devices MUST make
2940the Assist action available to the user at all times when running applications.
2941The Assist action SHOULD be implemented as a long-press on the Home button or a
2942swipe-up gesture on the software Home key. This function MAY be implemented via
2943another physical button, software key, or gesture, but MUST be accessible with
2944a single action (e.g. tap, double-click, or gesture) when other navigation keys
2945are visible.</p>
2946
2947<p>Device implementations MAY use a distinct portion of the screen to display the
2948navigation keys, but if so, MUST meet these requirements:</p>
2949
2950<ul>
2951 <li>Device implementation navigation keys MUST use a distinct portion of the
2952screen, not available to applications, and MUST NOT obscure or otherwise
2953interfere with the portion of the screen available to applications.</li>
2954 <li>Device implementations MUST make available a portion of the display to
2955applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2956 <li>Device implementations MUST display the navigation keys when applications do
2957not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2958 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2959profile&rdquo; (eg. dimmed) mode when applications specify
2960SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2961 <li>Device implementations MUST hide the navigation keys when applications specify
2962SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2963</ul>
2964
2965<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2966
2967<div class="note">
2968<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2969</div>
2970
2971
2972<p>Device implementations SHOULD have a pointer input system of some kind (either
2973mouse-like or touch). However, if a device implementation does not support a
2974pointer input system, it MUST NOT report the android.hardware.touchscreen or
2975android.hardware.faketouch feature constant. Device implementations that do
2976include a pointer input system:</p>
2977
2978<ul>
2979 <li>SHOULD support fully independently tracked pointers, if the device input system
2980supports multiple pointers.</li>
2981 <li>MUST report the value of android.content.res.Configuration.touchscreen [<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>] corresponding to the type of the specific touchscreen on the device.</li>
2982</ul>
2983
2984<p>Android includes support for a variety of touchscreens, touch pads, and fake
2985touch input devices. Touchscreen based device implementations are associated
2986with a display [<a href="http://source.android.com/devices/tech/input/touch-devices.html">Resources, 70</a>] such that the user has the impression of directly manipulating items on
2987screen. Since the user is directly touching the screen, the system does not
2988require any additional affordances to indicate the objects being manipulated.
2989In contrast, a fake touch interface provides a user input system that
2990approximates a subset of touchscreen capabilities. For example, a mouse or
2991remote control that drives an on-screen cursor approximates touch, but requires
2992the user to first point or focus then click. Numerous input devices like the
2993mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2994trackpad can support fake touch interactions. Android includes the feature
2995constant android.hardware.faketouch, which corresponds to a high-fidelity
2996non-touch (pointer-based) input device such as a mouse or trackpad that can
2997adequately emulate touch-based input (including basic gesture support), and
2998indicates that the device supports an emulated subset of touchscreen
2999functionality. Device implementations that declare the fake touch feature MUST
3000meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
3001
3002<p>Device implementations MUST report the correct feature corresponding to the
3003type of input used. Device implementations that include a touchscreen
3004(single-touch or better) MUST report the platform feature constant
3005android.hardware.touchscreen. Device implementations that report the platform
3006feature constant android.hardware.touchscreen MUST also report the platform
3007feature constant android.hardware.faketouch. Device implementations that do not
3008include a touchscreen (and rely on a pointer device only) MUST NOT report any
3009touchscreen feature, and MUST report only android.hardware.faketouch if they
3010meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
3011
3012<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
3013
3014
3015<p>Device implementations that declare support for android.hardware.faketouch:</p>
3016
3017<ul>
3018 <li>MUST report the absolute X and Y screen positions of the pointer location and
3019display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
3020 <li>MUST report touch event with the action code that specifies the state change
3021that occurs on the pointer going down or up on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
3022 <li>MUST support pointer down and up on an object on the screen, which allows users
3023to emulate tap on an object on the screen.</li>
3024 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
3025place on an object on the screen within a time threshold, which allows users to
3026emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
3027 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
3028any other arbitrary point on the screen, followed by a pointer up, which allows
3029users to emulate a touch drag.</li>
3030 <li>MUST support pointer down then allow users to quickly move the object to a
3031different position on the screen and then pointer up on the screen, which
3032allows users to fling an object on the screen.</li>
3033</ul>
3034
3035<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
3036MUST meet the requirements for faketouch above, and MUST also support distinct
3037tracking of two or more independent pointer inputs.</p>
3038
3039<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
3040
3041
3042<p>Android Television device implementations MUST support button mappings for game
3043controllers as listed below. The upstream Android implementation includes
3044implementation for game controllers that satisfies this requirement. </p>
3045
3046<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3047
3048
3049<p>Android Television device implementations MUST support the following key
3050mappings:</p>
3051<table>
3052 <tr>
3053 <th>Button</th>
3054 <th>HID Usage</strong><sup>2</sup></td>
3055 <th>Android Button</th>
3056 </tr>
3057 <tr>
3058 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3059 <td>0x09 0x0001</td>
3060 <td>KEYCODE_BUTTON_A (96)</td>
3061 </tr>
3062 <tr>
3063 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3064 <td>0x09 0x0002</td>
3065 <td>KEYCODE_BUTTON_B (97)</td>
3066 </tr>
3067 <tr>
3068 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3069 <td>0x09 0x0004</td>
3070 <td>KEYCODE_BUTTON_X (99)</td>
3071 </tr>
3072 <tr>
3073 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3074 <td>0x09 0x0005</td>
3075 <td>KEYCODE_BUTTON_Y (100)</td>
3076 </tr>
3077 <tr>
3078 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
3079
3080<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_DOWN">D-pad down</a><sup>1</sup></td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3081 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3082 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3083 </tr>
3084 <tr>
3085 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3086
3087<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_RIGHT">D-pad right</a><sup>1</sup></td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3088 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3089 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3090 </tr>
3091 <tr>
3092 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3093 <td>0x09 0x0007</td>
3094 <td>KEYCODE_BUTTON_L1 (102)</td>
3095 </tr>
3096 <tr>
3097 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3098 <td>0x09 0x0008</td>
3099 <td>KEYCODE_BUTTON_R1 (103)</td>
3100 </tr>
3101 <tr>
3102 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3103 <td>0x09 0x000E</td>
3104 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3105 </tr>
3106 <tr>
3107 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3108 <td>0x09 0x000F</td>
3109 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3110 </tr>
3111 <tr>
3112 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3113 <td>0x0c 0x0223</td>
3114 <td>KEYCODE_HOME (3)</td>
3115 </tr>
3116 <tr>
3117 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3118 <td>0x0c 0x0224</td>
3119 <td>KEYCODE_BACK (4)</td>
3120 </tr>
3121</table>
3122
3123
3124<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3125
3126<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3127
3128<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3129Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3130Report Size of 4. The logical value is defined to be the clockwise rotation
3131away from the vertical axis; for example, a logical value of 0 represents no
3132rotation and the up button being pressed, while a logical value of 1 represents
3133a rotation of 45 degrees and both the up and left keys being pressed.</p>
3134
3135<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3136
3137<table>
3138 <tr>
3139 <th>Analog Controls</strong><sup>1</sup></td>
3140 <th>HID Usage</th>
3141 <th>Android Button</th>
3142 </tr>
3143 <tr>
3144 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3145 <td>0x02 0x00C5</td>
3146 <td>AXIS_LTRIGGER </td>
3147 </tr>
3148 <tr>
3149 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3150 <td>0x02 0x00C4</td>
3151 <td>AXIS_RTRIGGER </td>
3152 </tr>
3153 <tr>
3154 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3155 <td>0x01 0x0030</p>
3156
3157<p>0x01 0x0031</td>
3158 <td>AXIS_X</p>
3159
3160<p>AXIS_Y</td>
3161 </tr>
3162 <tr>
3163 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3164 <td>0x01 0x0032</p>
3165
3166<p>0x01 0x0035</td>
3167 <td>AXIS_Z</p>
3168
3169<p>AXIS_RZ</td>
3170 </tr>
3171</table>
3172
3173
3174<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3175
3176<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3177
3178
3179<p>Android Television device implementations SHOULD provide a remote control to
3180allow users to access the TV interface. The remote control MAY be a physical
3181remote or can be a software-based remote that is accessible from a mobile phone
3182or tablet. The remote control MUST meet the requirements defined below.</p>
3183
3184<ul>
3185 <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>
3186 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3187support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3188</ul>
3189
3190<h2 id="7_3_sensors">7.3. Sensors</h2>
3191
3192
3193<p>Android includes APIs for accessing a variety of sensor types. Devices
3194implementations generally MAY omit these sensors, as provided for in the
3195following subsections. If a device includes a particular sensor type that has a
3196corresponding API for third-party developers, the device implementation MUST
3197implement that API as described in the Android SDK documentation and the
3198Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3199
3200<ul>
3201 <li>MUST accurately report the presence or absence of sensors per the
3202android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3203 <li>MUST return an accurate list of supported sensors via the
3204SensorManager.getSensorList() and similar methods.</li>
3205 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3206true or false as appropriate when applications attempt to register listeners,
3207not calling sensor listeners when the corresponding sensors are not present;
3208etc.).</li>
3209 <li>MUST report all sensor measurements using the relevant International System of
3210Units (metric) values for each sensor type as defined in the Android SDK
3211documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3212 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3213documentation, representing the time the event happened and synchronized with
3214the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3215are <strong>STRONGLY RECOMMENDED</strong> to meet these requirement so they will be able to upgrade to the future
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3216platform releases where this might become a REQUIRED component. The
3217synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3218</ul>
3219
3220<p>The list above is not comprehensive; the documented behavior of the Android SDK
3221and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3222
3223<p>Some sensor types are composite, meaning they can be derived from data provided
3224by one or more other sensors. (Examples include the orientation sensor, and the
3225linear acceleration sensor.) Device implementations SHOULD implement these
3226sensor types, when they include the prerequisite physical sensors as described
3227in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3228If a device implementation includes a composite sensor it MUST implement the
3229sensor as described in the Android Open Source documentation on composite
3230sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3231
3232<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3233continuously [<a href="https://source.android.com/devices/sensors/report-modes.html#continuous">Resources, 77</a>]. For any API indicated by the Android SDK documentation to be a continuous
3234sensor, device implementations MUST continuously provide periodic data samples
3235that SHOULD have a jitter below 3%, where jitter is defined as the standard
3236deviation of the difference of the reported timestamp values between
3237consecutive events.</p>
3238
3239<p>Note that the device implementations MUST ensure that the sensor event stream
3240MUST NOT prevent the device CPU from entering a suspend state or waking up from
3241a suspend state.</p>
3242
3243<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3244exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3245
3246<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3247
3248
3249<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3250devices and Android Watch devices are STRONGLY RECOMMENDED to include this
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3251sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3252
3253<ul>
3254 <li>MUST implement and report TYPE_ACCELEROMETER sensor [<a href="http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER">Resources, 78</a>].</li>
3255 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3256 Android Watch devices as such devices have a stricter power constraint and
3257 100 Hz for all other device types.</li>
3258 <li>SHOULD report events up to at least 200 Hz.</li>
3259 <li>MUST comply with the Android sensor coordinate system as detailed in the
3260Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3261 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3262more on any axis.</li>
3263 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3264least 16-bits.</li>
3265 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3266cycle and compensated, and preserve the compensation parameters between device
3267reboots.</li>
3268 <li>SHOULD be temperature compensated.</li>
3269 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3270deviation should be calculated on a per axis basis on samples collected over a
3271period of at least 3 seconds at the fastest sampling rate.</li>
3272 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3273TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3274Android SDK document. Existing and new Android devices are <strong>STRONGLY RECOMMENDED</strong> to implement the TYPE_SIGNIFICANT_MOTION composite sensor. If any of these
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3275sensors are implemented, the sum of their power consumption MUST always be less
3276than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3277dynamic or static condition.</li>
3278 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3279TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3280TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3281are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3282 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3283and a magnetometer sensor is also included.</li>
3284</ul>
3285
3286<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3287
3288
3289<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3290device does include a 3-axis magnetometer, it:</p>
3291
3292<ul>
3293 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3294TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3295STRONGLY RECOMMENDED to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3296 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3297report events up to at least 50 Hz.</li>
3298 <li>MUST comply with the Android sensor coordinate system as detailed in the
3299Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3300 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3301saturating.</li>
3302 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3303below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3304and static (magnet-induced) magnetic fields.</li>
3305 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3306equal or denser than 0.2 &micro;.</li>
3307 <li>SHOULD be temperature compensated.</li>
3308 <li>MUST support online calibration and compensation of the hard iron bias, and
3309preserve the compensation parameters between device reboots.</li>
3310 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3311while in use or during the production of the device.</li>
3312 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3313collected over a period of at least 3 seconds at the fastest sampling rate, no
3314greater than 0.5 &micro;T.</li>
3315 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3316sensor and a gyroscope sensor is also included.</li>
3317 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3318sensor is also implemented. However if implemented, it MUST consume less than
331910 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3320mode at 10 Hz.</li>
3321</ul>
3322
3323<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3324
3325
3326<p>Device implementations SHOULD include a GPS receiver. If a device
3327implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3328
3329<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3330
3331
3332<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3333Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3334also included. If a device implementation includes a gyroscope, it:</p>
3335
3336<ul>
3337 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3338TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3339STRONGLY RECOMMENDED to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3340 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3341 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3342 Android Watch devices as such devices have a stricter power constraint and
3343 100 Hz for all other device types.</li>
3344 <li>SHOULD report events up to at least 200 Hz.</li>
3345 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
334616-bits or more.</li>
3347 <li>MUST be temperature compensated.</li>
3348 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3349parameters between device reboots.</li>
3350 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3351or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3352be constrained by this value. In other words, if you measure the variance of
3353the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3354 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3355sensor and a magnetometer sensor is also included.</li>
3356 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3357TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3358TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3359are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3360</ul>
3361
3362<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3363
3364
3365<p>Device implementations SHOULD include a barometer (ambient air pressure
3366sensor). If a device implementation includes a barometer, it:</p>
3367
3368<ul>
3369 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3370 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3371 <li>MUST have adequate precision to enable estimating altitude.</li>
3372 <li>MUST be temperature compensated.</li>
3373</ul>
3374
3375<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3376
3377
3378<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3379If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3380measure the ambient (room) temperature in degrees Celsius.</p>
3381
3382<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3383present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3384temperature of the device CPU, and it MUST NOT measure any other temperature.
3385Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3386
3387<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3388
3389
3390<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3391
3392<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3393
3394
3395<p>Device implementations MAY include a proximity sensor. Devices that can make a
3396voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3397SHOULD include a proximity sensor. If a device implementation does include a
3398proximity sensor, it:</p>
3399
3400<ul>
3401 <li>MUST measure the proximity of an object in the same direction as the screen.
3402That is, the proximity sensor MUST be oriented to detect objects close to the
3403screen, as the primary intent of this sensor type is to detect a phone in use
3404by the user. If a device implementation includes a proximity sensor with any
3405other orientation, it MUST NOT be accessible through this API.</li>
3406 <li>MUST have 1-bit of accuracy or more.</li>
3407</ul>
3408
3409<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3410
3411
3412<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3413
3414
3415<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3416to hardware related to placing voice calls and sending SMS messages via a GSM
3417or CDMA network. While these voice calls may or may not be packet-switched,
3418they are for the purposes of Android considered independent of any data
3419connectivity that may be implemented using the same network. In other words,
3420the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3421calls and SMS. For instance, device implementations that cannot place calls or
3422send/receive SMS messages MUST NOT report the android.hardware.telephony
3423feature or any subfeatures, regardless of whether they use a cellular network
3424for data connectivity.</p>
3425
3426<p>Android MAY be used on devices that do not include telephony hardware. That is,
3427Android is compatible with devices that are not phones. However, if a device
3428implementation does include GSM or CDMA telephony, it MUST implement full
3429support for the API for that technology. Device implementations that do not
3430include telephony hardware MUST implement the full APIs as no-ops.</p>
3431
3432<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3433
3434<div class="note">
3435<p>Android Television device implementations MUST include Wi-Fi support.</p>
3436</div>
3437
3438
3439<p>Android Television device implementations MUST include support for one or more
3440forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3441implementation SHOULD include support for one or more forms of 802.11. If a
3442device implementation does include support for 802.11 and exposes the
3443functionality to a third-party application, it MUST implement the corresponding
3444Android API and:</p>
3445
3446<ul>
3447 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3448 <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, 79</a>].</li>
3449 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3450(224.0.0.251) at any time of operation including when the screen is not in an
3451active state.</li>
3452</ul>
3453
3454<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3455
3456
3457<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3458peer-to-peer). If a device implementation does include support for Wi-Fi
3459Direct, it MUST implement the corresponding Android API as described in the SDK
3460documentation [<a href="http://developer.android.com/reference/android/net/wifi/p2p/WifiP2pManager.html">Resources, 80</a>]. If a device implementation includes support for Wi-Fi Direct, then it:</p>
3461
3462<ul>
3463 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3464 <li>MUST support regular Wi-Fi operation.</li>
3465 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3466</ul>
3467
3468<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3469
3470<div class="note">
3471<p>Android Television device implementations MUST include support for Wi-Fi
3472Tunneled Direct Link Setup (TDLS).</p>
3473</div>
3474
3475
3476<p>Android Television device implementations MUST include support for Wi-Fi
3477Tunneled Direct Link Setup (TDLS) and other types of Android device
3478implementations SHOULD include support for Wi-Fi TDLS as described in the
3479Android SDK Documentation [<a href="http://developer.android.com/reference/android/net/wifi/WifiManager.html">Resources, 81</a>]. If a device implementation does include support for TDLS and TDLS is enabled
3480by the WiFiManager API, the device:</p>
3481
3482<ul>
3483 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3484 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3485than going through the Wi-Fi access point.</li>
3486</ul>
3487
3488<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3489
3490<div class="note">
3491<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3492Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3493</div>
3494
3495
3496<p>Android includes support for Bluetooth and Bluetooth Low Energy [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>]. Device implementations that include support for Bluetooth and Bluetooth Low
3497Energy MUST declare the relevant platform features (android.hardware.bluetooth
3498and android.hardware.bluetooth_le respectively) and implement the platform
3499APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3500as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3501device implementations MUST support Bluetooth and Bluetooth LE. </p>
3502
3503<p>Device implementations including support for Bluetooth Low Energy:</p>
3504
3505<ul>
3506 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3507 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3508described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3509 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3510implementing the ScanFilter API [<a href="https://developer.android.com/reference/android/bluetooth/le/ScanFilter.html">Resources, 83</a>], and MUST report the correct value of where the filtering logic is implemented whenever queried via the
3511android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3512 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3513if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3514android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3515 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3516MUST report &lsquo;false&rsquo; whenever queried via the
3517android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3518</ul>
3519
3520<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3521
3522
3523<p>Device implementations SHOULD include a transceiver and related hardware for
3524Near-Field Communications (NFC). If a device implementation does include NFC
3525hardware and plans to make it available to third-party apps, then it:</p>
3526
3527<ul>
3528 <li>MUST report the android.hardware.nfc feature from the
3529android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3530 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3531standards:
3532 <ul>
3533 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3534Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3535following NFC standards:
3536 <ul>
3537 <li>NfcA (ISO14443-3A)</li>
3538 <li>NfcB (ISO14443-3B)</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3539 <li>NfcF (JIS X 6319-4)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3540 <li>IsoDep (ISO 14443-4)</li>
3541 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3542 </ul>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3543 <li>MUST be capable of reading and writing NDEF messages as well as raw
3544 data via the following NFC standards:</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3545 <ul>
3546 <li>NfcV (ISO 15693)</li>
3547 </ul></li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3548 <li>SHOULD be capable of reading the barcode and URL (if encoded) of
3549 Thinfilm NFC Barcode
3550 [<a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">Resources, XX</a>] products.
3551 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3552 <li>MUST be capable of transmitting and receiving data via the following
3553peer-to-peer standards and protocols:
3554 <ul>
3555 <li>ISO 18092</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3556 <li>LLCP 1.2 (defined by the NFC Forum)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3557 <li>SDP 1.0 (defined by the NFC Forum)</li>
3558 <li>NDEF Push Protocol [<a href="http://static.googleusercontent.com/media/source.android.com/en/us/compatibility/ndef-push-protocol.pdf">Resources, 84</a>]</li>
3559 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3560 </ul></li>
3561 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3562 <ul>
3563 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3564default SNEP server MUST be dispatched to applications using the
3565android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3566MUST NOT disable dispatch of incoming NDEF message.</li>
3567 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3568settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3569 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3570processed the same way as the SNEP default server.</li>
3571 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3572default SNEP server when Android Beam is enabled. If no default SNEP server is
3573found then the client MUST attempt to send to an NPP server.</li>
3574 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3575android.nfc.NfcAdapter.setNdefPushMessage, and
3576android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3577android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3578 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3579sending outbound P2P NDEF messages.</li>
3580 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3581using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3582 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3583Bluetooth Object Push Profile. Device implementations MUST support connection
3584handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3585implementing the &ldquo;Connection Handover version 1.2&rdquo; [<a href="http://members.nfc-forum.org/specs/spec_list/#conn_handover">Resources, 87</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, 88</a>] specs from the NFC Forum. Such an implementation MUST implement the handover
3586LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3587handover request/select records over NFC, and it MUST use the Bluetooth Object
3588Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3589remain compatible with Android 4.1 devices), the implementation SHOULD still
3590accept SNEP GET requests for exchanging the handover request/select records
3591over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3592for performing connection handover.</li>
3593 </ul></li>
3594 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3595 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3596active and the lock-screen unlocked.</li>
3597</ul>
3598</ul>
3599
3600<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3601Forum specifications cited above.)</p>
3602
3603<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3604device implementation does include an NFC controller chipset capable of HCE and
3605Application ID (AID) routing, then it:</p>
3606
3607<ul>
3608 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3609 <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, 10</a>].</li>
3610</ul>
3611
3612<p>Additionally, device implementations MAY include reader/writer support for the
3613following MIFARE technologies.</p>
3614
3615<ul>
3616 <li>MIFARE Classic</li>
3617 <li>MIFARE Ultralight</li>
3618 <li>NDEF on MIFARE Classic</li>
3619</ul>
3620
3621<p>Note that Android includes APIs for these MIFARE types. If a device
3622implementation supports MIFARE in the reader/writer role, it:</p>
3623
3624<ul>
3625 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3626 <li>MUST report the feature com.nxp.mifare from the
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3627android.content.pm.PackageManager.hasSystemFeature() method <a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">[Resources, 53]</a>. Note that this is not a standard Android feature and as such does not appear
3628as a constant in the android.content.pm.PackageManager class.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3629 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3630feature unless it also implements general NFC support as described in this
3631section.</li>
3632</ul>
3633
3634<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3635the android.hardware.nfc feature from the
3636android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>, and MUST implement the Android NFC API as a no-op.</p>
3637
3638<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3639protocol-independent data representation format, device implementations MUST
3640implement these APIs even if they do not include support for NFC or declare the
3641android.hardware.nfc feature.</p>
3642
3643<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3644
3645
3646<p>Device implementations MUST include support for one or more forms of data
3647networking. Specifically, device implementations MUST include support for at
3648least one data standard capable of 200Kbit/sec or greater. Examples of
3649technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3650Ethernet, Bluetooth PAN, etc.</p>
3651
3652<p>Device implementations where a physical networking standard (such as Ethernet)
3653is the primary data connection SHOULD also include support for at least one
3654common wireless data standard, such as 802.11 (Wi-Fi).</p>
3655
3656<p>Devices MAY implement more than one form of data connectivity.</p>
3657
3658<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3659
3660
3661<p>Device implementations MUST have the master auto-sync setting on by default so
3662that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3663
3664<h2 id="7_5_cameras">7.5. Cameras</h2>
3665
3666
3667<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3668front-facing camera. A rear-facing camera is a camera located on the side of
3669the device opposite the display; that is, it images scenes on the far side of
3670the device, like a traditional camera. A front-facing camera is a camera
3671located on the same side of the device as the display; that is, a camera
3672typically used to image the user, such as for video conferencing and similar
3673applications.</p>
3674
3675<p>If a device implementation includes at least one camera, it SHOULD be possible
3676for an application to simultaneously allocate 3 bitmaps equal to the size of
3677the images produced by the largest-resolution camera sensor on the device.</p>
3678
3679<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3680
3681
3682<p>Device implementations SHOULD include a rear-facing camera. If a device
3683implementation includes at least one rear-facing camera, it:</p>
3684
3685<ul>
3686 <li>MUST report the feature flag android.hardware.camera and
3687android.hardware.camera.any.</li>
3688 <li>MUST have a resolution of at least 2 megapixels.</li>
3689 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3690the camera driver (transparent to application software).</li>
3691 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3692 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3693lit while an android.hardware.Camera.PreviewCallback instance has been
3694registered on a Camera preview surface, unless the application has explicitly
3695enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3696of a Camera.Parameters object. Note that this constraint does not apply to the
3697device&rsquo;s built-in system camera application, but only to third-party
3698applications using Camera.PreviewCallback.</li>
3699</ul>
3700
3701<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3702
3703
3704<p>Device implementations MAY include a front-facing camera. If a device
3705implementation includes at least one front-facing camera, it:</p>
3706
3707<ul>
3708 <li>MUST report the feature flag android.hardware.camera.any and
3709android.hardware.camera.front.</li>
3710 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3711 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3712camera API in Android has specific support for front-facing cameras and device
3713implementations MUST NOT configure the API to to treat a front-facing camera as
3714the default rear-facing camera, even if it is the only camera on the device.</li>
3715 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3716cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3717 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3718CameraPreview, as follows:
3719 <ul>
3720 <li>If the device implementation is capable of being rotated by user (such as
3721automatically via an accelerometer or manually via user input), the camera
3722preview MUST be mirrored horizontally relative to the device&rsquo;s current
3723orientation.</li>
3724 <li>If the current application has explicitly requested that the Camera display be
3725rotated via a call to the android.hardware.Camera.setDisplayOrientation()[<a href="http://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int)">Resources, 90</a>] method, the camera preview MUST be mirrored horizontally relative to the
3726orientation specified by the application.</li>
3727 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3728axis.</li>
3729 </ul></li>
3730 <li>MUST mirror the image displayed by the postview in the same manner as the
3731camera preview image stream. If the device implementation does not support
3732postview, this requirement obviously does not apply.</li>
3733 <li>MUST NOT mirror the final captured still image or video streams returned to
3734application callbacks or committed to media storage.</li>
3735</ul>
3736
3737<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3738
3739
3740<p>Device implementations with USB host mode MAY include support for an external
3741camera that connects to the USB port. If a device includes support for an
3742external camera, it:</p>
3743
3744<ul>
3745 <li>MUST declare the platform feature android.hardware.camera.external and
3746android.hardware camera.any.</li>
3747 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3748 <li>MAY support multiple cameras.</li>
3749</ul>
3750
3751<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3752high-quality unencoded streams (i.e. raw or independently compressed picture
3753streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3754unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3755device implementation.</p>
3756
3757<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3758
3759
3760<p>Android includes two API packages to access the camera, the newer
3761android.hardware.camera2 API expose lower-level camera control to the app,
3762including efficient zero-copy burst/streaming flows and per-frame controls of
3763exposure, gain, white balance gains, color conversion, denoising, sharpening,
3764and more.</p>
3765
3766<p>The older API package, android.hardware.Camera, is marked as deprecated in
3767Android 5.0 but as it should still be available for apps to use Android device
3768implementations MUST ensure the continued support of the API as described in
3769this section and in the Android SDK.</p>
3770
3771<p>Device implementations MUST implement the following behaviors for the
3772camera-related APIs, for all available cameras:</p>
3773
3774<ul>
3775 <li>If an application has never called
3776android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3777use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3778application callbacks.</li>
3779 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3780and the system calls the onPreviewFrame() method when the preview format is
3781YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3782be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3783 <li>For android.hardware.Camera, device implementations MUST support the YV12
3784format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3785camera previews for both front- and rear-facing cameras. (The hardware video
3786encoder and camera may use any native pixel format, but the device
3787implementation MUST support conversion to YV12.)</li>
3788 <li>For android.hardware.camera2, device implementations must support the
3789android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3790formats as outputs through the android.media.ImageReader API.</li>
3791</ul>
3792
3793<p>Device implementations MUST still implement the full Camera API included in the
3794Android SDK documentation [<a href="http://developer.android.com/reference/android/hardware/Camera.html">Resources, 91</a>], regardless of whether the device includes hardware autofocus or other
3795capabilities. For instance, cameras that lack autofocus MUST still call any
3796registered android.hardware.Camera.AutoFocusCallback instances (even though
3797this has no relevance to a non-autofocus camera.) Note that this does apply to
3798front-facing cameras; for instance, even though most front-facing cameras do
3799not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3800
3801<p>Device implementations MUST recognize and honor each parameter name defined as
3802a constant on the android.hardware.Camera.Parameters class, if the underlying
3803hardware supports the feature. If the device hardware does not support a
3804feature, the API must behave as documented. Conversely, device implementations
3805MUST NOT honor or recognize string constants passed to the
3806android.hardware.Camera.setParameters() method other than those documented as
3807constants on the android.hardware.Camera.Parameters. That is, device
3808implementations MUST support all standard Camera parameters if the hardware
3809allows, and MUST NOT support custom Camera parameter types. For instance,
3810device implementations that support image capture using high dynamic range
3811(HDR) imaging techniques MUST support camera parameter Camera.SCENE_MODE_HDR [<a href="http://developer.android.com/reference/android/hardware/Camera.Parameters.html">Resources, 92</a>].</p>
3812
3813<p>Because not all device implementations can fully support all the features of
3814the android.hardware.camera2 API, device implementations MUST report the proper
3815level of support with the android.info.supportedHardwareLevel property as
3816described in the Android SDK [<a href="https://developer.android.com/reference/android/hardware/camera2/CameraCharacteristics.html#INFO_SUPPORTED_HARDWARE_LEVEL">Resources, 93]</a> and report the appropriate framework feature flags [<a href="http://source.android.com/devices/camera/versioning.html">Resources, 94]</a>. </p>
3817
3818<p>Device implementations MUST also declare its Individual camera capabilities of
3819android.hardware.camera2 via the android.request.availableCapabilities property
3820and declare the appropriate feature flags [<a href="http://source.android.com/devices/camera/versioning.html">Resources, 94]</a>; a device must define the feature flag if any of its attached camera devices supports the feature.</p>
3821
3822<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3823whenever a new picture is taken by the camera and the entry of the picture has
3824been added to the media store.</p>
3825
3826<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3827whenever a new video is recorded by the camera and the entry of the picture has
3828been added to the media store.</p>
3829
3830<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3831
3832
3833<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3834long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3835when the device is held in the landscape orientation, cameras MUST capture
3836images in the landscape orientation. This applies regardless of the device&rsquo;s
3837natural orientation; that is, it applies to landscape-primary devices as well
3838as portrait-primary devices.</p>
3839
3840<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3841
3842
3843<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3844
3845<div class="note">
3846<p>Android Television devices MUST have at least 5GB of non-volatile storage
3847available for application private data.</p>
3848</div>
3849
3850
3851<p>The memory available to the kernel and userspace on device implementations MUST
3852be at least equal or larger than the minimum values specified by the following
3853table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3854<table>
3855 <tr>
3856 <th>Density and screen size</th>
3857 <th>32-bit device</th>
3858 <th>64-bit device</th>
3859 </tr>
3860 <tr>
3861 <td>Android Watch devices (due to smaller screens)</td>
3862 <td>416MB</td>
3863 <td>Not applicable</td>
3864 </tr>
3865 <tr>
3866 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3867 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3868 <li class="table_list">mdpi or lower on large screens</li>
3869 <li class="table_list">ldpi or lower on extra large screens</li>
3870 </ul></td>
3871 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3872 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3873 </tr>
3874 <tr>
3875 <td><ul>
3876 <li class="table_list">xhdpi or higher on small/normal screens</li>
3877 <li class="table_list">hdpi or higher on large screens</li>
3878 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3879 <td>512MB</td>
3880 <td>832MB</td>
3881 </tr>
3882 <tr>
3883 <td><ul>
3884 <li class="table_list">400dpi or higher on small/normal screens</li>
3885 <li class="table_list">xhdpi or higher on large screens</li>
3886 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3887 <td>896MB</td>
3888 <td>1280MB</td>
3889 </tr>
3890 <tr>
3891 <td><ul>
3892 <li class="table_list">560dpi or higher on small/normal screens</li>
3893 <li class="table_list">400dpi or higher on large screens</li>
3894 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3895 <td>1344MB</td>
3896 <td>1824MB</td>
3897 </tr>
3898</table>
3899
3900
3901<p>The minimum memory values MUST be in addition to any memory space already
3902dedicated to hardware components such as radio, video, and so on that is not
3903under the kernel&rsquo;s control.</p>
3904
3905<p>Device implementations with less than 512MB of memory available to the kernel
3906and userspace, unless an Android Watch, MUST return the value "true" for
3907ActivityManager.isLowRamDevice().</p>
3908
3909<p>Android Television devices MUST have at least 5GB and other device
3910implementations MUST have at least 1.5GB of non-volatile storage available for
3911application private data. That is, the /data partition MUST be at least 5GB for
3912Android Television devices and at least 1.5GB for other device implementations.
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3913Device implementations that run Android are <strong>STRONGLY RECOMMENDED</strong> to have at least 3GB of non-volatile storage for application private data so
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3914they will be able to upgrade to the future platform releases.</p>
3915
3916<p>The Android APIs include a Download Manager that applications MAY use to
3917download data files [<a href="http://developer.android.com/reference/android/app/DownloadManager.html">Resources, 95</a>]. The device implementation of the Download Manager MUST be capable of
3918downloading individual files of at least 100MB in size to the default &ldquo;cache"
3919location.</p>
3920
3921<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3922
3923
3924<p>Device implementations MUST offer shared storage for applications also often
3925referred as &ldquo;shared external storage&rdquo;. </p>
3926
3927<p>Device implementations MUST be configured with shared storage mounted by
3928default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3929path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3930to the actual mount point.</p>
3931
3932<p>Device implementations MAY have hardware for user-accessible removable storage,
3933such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3934shared storage requirement, the device implementation:</p>
3935
3936<ul>
3937 <li>MUST implement a toast or pop-up user interface warning the user when there is
3938no SD card.</li>
3939 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3940and other material available at time of purchase that the SD card has to be
3941separately purchased.</li>
3942 <li>MUST mount the SD card by default.</li>
3943</ul>
3944
3945<p>Alternatively, device implementations MAY allocate internal (non-removable)
3946storage as shared storage for apps as included in the upstream Android Open
3947Source Project; device implementations SHOULD use this configuration and
3948software implementation. If a device implementation uses internal
3949(non-removable) storage to satisfy the shared storage requirement, that storage
3950MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3951symbolic link to the physical location if it is mounted elsewhere).</p>
3952
3953<p>Device implementations MUST enforce as documented the
3954android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3955Shared storage MUST otherwise be writable by any application that obtains that
3956permission.</p>
3957
3958<p>Device implementations that include multiple shared storage paths (such as both
3959an SD card slot and shared internal storage) MUST NOT allow Android
3960applications to write to the secondary external storage, except for their
3961package-specific directories on the secondary external storage, but SHOULD
3962expose content from both storage paths transparently through Android&rsquo;s media
3963scanner service and android.provider.MediaStore.</p>
3964
3965<p>Regardless of the form of shared storage used, if the device implementation
3966has a USB port with USB peripheral mode support, it MUST provide some mechanism
3967to access the contents of shared storage from a host computer. Device
3968implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3969to satisfy this requirement. If the device implementation supports Media
3970Transfer Protocol, it:</p>
3971
3972<ul>
3973 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3974[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3975 <li>SHOULD report a USB device class of 0x00.</li>
3976 <li>SHOULD report a USB interface name of 'MTP'.</li>
3977</ul>
3978
3979<h2 id="7_7_usb">7.7. USB</h2>
3980
3981
3982<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3983USB host mode.</p>
3984
3985<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3986
3987<ul>
3988 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3989-C USB port.</li>
3990 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3991new Android devices are <strong>STRONGLY RECOMMENDED to meet these requirements</strong> so they will be able to upgrade to the future platform releases.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3992 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3993SHOULD either locate the port on the bottom of the device (according to natural
3994orientation) or enable software screen rotation for all apps (including home
3995screen), so that the display draws correctly when the device is oriented with
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]3996the 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>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3997 <li>It MUST allow a USB host connected with the Android device to access the
3998contents of the shared storage volume using either USB mass storage or Media
3999Transfer Protocol.</li>
4000 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
4001documented in the Android SDK documentation, and if it is an Android Handheld
4002device it MUST implement the AOA API. Device implementations implementing the
4003AOA specification:
4004 <ul>
4005 <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, 97</a>].</li>
4006 <li>MUST implement the USB audio class as documented in the Android SDK
4007documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
Unsuk Jungd94638a2015-09-29 20:50:56 -0700[diff] [blame]4008 <li>And also the USB mass storage class, MUST include the string "android"
4009at the end of the interface description <code>iInterface</code> string of the
4010USB mass storage</li>
4011 </ul>
4012 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4013 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]4014as specified in the USB battery charging specification [<a href="http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf">Resources, 99</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>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4015 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
4016the value of android.os.Build.SERIAL.</li>
4017</ul>
4018
4019<p>If a device implementation includes a USB port supporting host mode, it:</p>
4020
4021<ul>
4022 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
4023 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
4024cables adapting the port to a standard type-A or type-C USB port.</li>
4025 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
4026adapting the port to a standard type-A or type-C USB port.</li>
4027 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
4028documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
4029 <li>MUST implement the Android USB host API as documented in the Android SDK, and
4030MUST declare support for the hardware feature android.hardware.usb.host [<a href="http://developer.android.com/guide/topics/connectivity/usb/host.html">Resources, 100</a>].</li>
4031 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
4032as specified in the USB Battery Charging Specifications [<a href="http://www.usb.org/developers/docs/devclass_docs/USB_Battery_Charging_1.2.pdf">Resources, 99</a>].</li>
4033</ul>
4034
4035<h2 id="7_8_audio">7.8. Audio</h2>
4036
4037
4038<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
4039
4040<div class="note">
4041<p>Android Handheld, Watch, and Automotive implementations MUST include a
4042microphone.</p>
4043</div>
4044
4045
4046<p>Device implementations MAY omit a microphone. However, if a device
4047implementation omits a microphone, it MUST NOT report the
4048android.hardware.microphone feature constant, and MUST implement the audio
4049recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4050
4051<ul>
4052 <li>MUST report the android.hardware.microphone feature constant
4053 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
4054 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
4055</ul>
4056
4057<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4058
4059<div class="note">
4060<p>Android Watch devices MAY include an audio output.</p>
4061</div>
4062
4063<p>Device implementations including a speaker or with an audio/multimedia output
4064port for an audio output peripheral as a headset or an external speaker:</p>
4065
4066<ul>
4067 <li>MUST report the android.hardware.audio.output feature constant.</li>
4068 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4069 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4070</ul>
4071
4072<p>Conversely, if a device implementation does not include a speaker or audio
4073output port, it MUST NOT report the android.hardware.audio output feature, and
4074MUST implement the Audio Output related APIs as no-ops at least. </p>
4075
4076<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4077other types of Android device implementations MUST have an audio output and
4078declare android.hardware.audio.output.</p>
4079
4080<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4081
4082
4083<p>In order to be compatible with the headsets and other audio accessories using
4084the 3.5mm audio plug across the Android ecosystem [<a href="http://source.android.com/accessories/headset-spec.html">Resources, 101</a>], if a device implementation includes one or more analog audio ports, at least
4085one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4086implementation has a 4 conductor 3.5mm audio jack, it:</p>
4087
4088<ul>
4089 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4090microphone, and SHOULD support audio recording from stereo headsets with a
4091microphone.</li>
4092 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4093audio plugs with the OMTP pin-out order.</li>
4094 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4095the device implementation supports a microphone, and broadcast the
4096android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4097 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4098ranges of equivalent impedance between the microphone and ground conductors on
4099the audio plug:
4100 <ul>
4101 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4102 <li><strong>210&#45;290 Ohm</strong>: KEYCODE_VOLUME_UP</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4103 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4104 </ul></li>
4105 <li>SHOULD support the detection and mapping to the keycode for the following range
4106of equivalent impedance between the microphone and ground conductors on the
4107audio plug:
4108 <ul>
4109 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4110 </ul></li>
4111 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4112contacts on plug are touching their relevant segments on the jack.</li>
4113 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4114speaker impedance.</li>
4115 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4116</ul>
4117
4118<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4119
4120
4121<p>Some minimum performance criterias are critical to the user experience and
4122impacts the baseline assumptions developers would have when developing an app.
4123Android Watch devices SHOULD and other type of device implementations MUST meet
4124the following criteria:</p>
4125
4126<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4127
4128
4129<p>Device implementations MUST provide a smooth user interface by ensuring a
4130consistent frame rate and response times for applications and games. Device
4131implementations MUST meet the following requirements: </p>
4132
4133<ul>
4134 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4135often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4136 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4137list of 10K list entries as defined by the Android Compatibility Test Suite
4138(CTS) in less than 36 secs.</li>
4139 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4140application after it has been launched MUST take less than 1 second.</li>
4141</ul>
4142
4143<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4144
4145
4146<p>Device implementations MUST ensure internal storage file access performance consistency for read
4147and write operations. </p>
4148
4149<ul>
4150 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4151for a 256MB file using 10MB write buffer.</li>
4152 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4153256MB file using 4KB write buffer.</li>
4154 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4155a 256MB file using 10MB write buffer.</li>
4156 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4157256MB file using 4KB write buffer.</li>
4158</ul>
4159
4160<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4161
4162
4163<p>Device implementations MUST implement a security model consistent with the
4164Android platform security model as defined in Security and Permissions
4165reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>] in the Android developer documentation. Device implementations MUST support
4166installation of self-signed applications without requiring any additional
4167permissions/certificates from any third parties/authorities. Specifically,
4168compatible devices MUST support the security mechanisms described in the follow
4169subsections.</p>
4170
4171<h2 id="9_1_permissions">9.1. Permissions</h2>
4172
4173
4174<p>Device implementations MUST support the Android permissions model as defined in
4175the Android developer documentation [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>]. Specifically, implementations MUST enforce each permission defined as
4176described in the SDK documentation; no permissions may be omitted, altered, or
4177ignored. Implementations MAY add additional permissions, provided the new
4178permission ID strings are not in the android.* namespace.</p>
4179
Svetoslav4bbf7402015-09-11 14:45:48 -0700[diff] [blame]4180<p>Permissions with a protection level of dangerous are runtime permissions. Applications
4181with targetSdkVersion > 22 request them at runtime. The system MUST show a dedicated UI for the
4182user to decide whether to grant the requested runtime permissions and also provide a UI for the
4183user to manage runtime permissions. On the system there MUST be one and only one
4184implementation of both the UI for the user to accept runtime permissions and the UI for
4185the user to manage runtime permissions.</p>
4186
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4187<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4188
4189
4190<p>Device implementations MUST support the Android application sandbox model, in
4191which each application runs as a unique Unixstyle UID and in a separate
4192process. Device implementations MUST support running multiple applications as
4193the same Linux user ID, provided that the applications are properly signed and
4194constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4195
4196<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4197
4198
4199<p>Device implementations MUST support the Android file access permissions model
4200as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4201
4202<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4203
4204
4205<p>Device implementations MAY include runtime environments that execute
4206applications using some other software or technology than the Dalvik Executable
4207Format or native code. However, such alternate execution environments MUST NOT
4208compromise the Android security model or the security of installed Android
4209applications, as described in this section.</p>
4210
4211<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4212standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4213
4214<p>Alternate runtimes MUST NOT be granted access to resources protected by
4215permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4216&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4217
4218<p>Alternate runtimes MUST NOT permit applications to make use of features
4219protected by Android permissions restricted to system applications.</p>
4220
4221<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4222alternate runtimes:</p>
4223
4224<ul>
4225 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4226Linux user IDs, etc.).</li>
4227 <li>MAY provide a single Android sandbox shared by all applications using the
4228alternate runtime.</li>
4229 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4230sandbox of any other app installed on the device, except through the standard
4231Android mechanisms of shared user ID and signing certificate.</li>
4232 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4233corresponding to other Android applications.</li>
4234 <li>MUST NOT be launched with, be granted, or grant to other applications any
4235privileges of the superuser (root), or of any other user ID.</li>
4236</ul>
4237
4238<p>The .apk files of alternate runtimes MAY be included in the system image of a
4239device implementation, but MUST be signed with a key distinct from the key used
4240to sign other applications included with the device implementation.</p>
4241
4242<p>When installing applications, alternate runtimes MUST obtain user consent for
4243the Android permissions used by the application. If an application needs to
4244make use of a device resource for which there is a corresponding Android
4245permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4246user that the application will be able to access that resource. If the runtime
4247environment does not record application capabilities in this manner, the
4248runtime environment MUST list all permissions held by the runtime itself when
4249installing any application using that runtime.</p>
4250
4251<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4252
4253<div class="note">
4254<p>This feature is optional for all device types.</p>
4255</div>
4256
4257
4258<p>Android includes support for multiple users and provides support for full user
4259isolation [<a href="http://developer.android.com/reference/android/os/UserManager.html">Resources, 103]</a>. Device implementations MAY enable multiple users, but when enabled MUST meet
4260the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4261
4262<ul>
4263 <li>Device implementations that do not declare the android.hardware.telephony
4264feature flag MUST support restricted profiles, a feature that allows device
4265owners to manage additional users and their capabilities on the device. With
4266restricted profiles, device owners can quickly set up separate environments for
4267additional users to work in, with the ability to manage finer-grained
4268restrictions in the apps that are available in those environments.</li>
4269 <li>Conversely device implementations that declare the android.hardware.telephony
4270feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4271implementation of controls to enable /disable other users from accessing the
4272voice calls and SMS.</li>
4273 <li>Device implementations MUST, for each user, implement a security model
4274consistent with the Android platform security model as defined in Security and
4275Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4276 <li>Device implementations MAY support creating users and managed profiles via the
4277android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4278platform feature flag android.software.managed_users.
4279 <li>Device implementations that declare the feature flag
4280android.software.managed_users MUST use the upstream AOSP icon badge to
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4281represent the managed applications and other badge UI elements like Recents &amp;
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4282Notifications.</li>
4283 <li>Each user instance on an Android device MUST have separate and isolated
4284external storage directories. Device implementations MAY store multiple users'
4285data on the same volume or filesystem. However, the device implementation MUST
4286ensure that applications owned by and running on behalf a given user cannot
4287list, read, or write to data owned by any other user. Note that removable
4288media, such as SD card slots, can allow one user to access another&rsquo;s data by
4289means of a host PC. For this reason, device implementations that use removable
4290media for the external storage APIs MUST encrypt the contents of the SD card if
4291multiuser is enabled using a key stored only on non-removable media accessible
4292only to the system. As this will make the media unreadable by a host PC, device
4293implementations will be required to switch to MTP or a similar system to
4294provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4295implementations MAY but SHOULD NOT enable multi-user if they use removable
4296media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4297</ul>
4298
4299<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4300
4301
4302<p>Android includes support for warning users of any outgoing premium SMS message
4303[<a href="http://en.wikipedia.org/wiki/Short_code">Resources, 106</a>] . Premium SMS messages are text messages sent to a service registered with a
4304carrier that may incur a charge to the user. Device implementations that
4305declare support for android.hardware.telephony MUST warn users before sending a
4306SMS message to numbers identified by regular expressions defined in
4307/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4308Project provides an implementation that satisfies this requirement.</p>
4309
4310<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4311
4312
4313<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4314(SELinux) mandatory access control (MAC) system and other security features in
4315the Linux kernel. SELinux or any other security features, if implemented below
4316the Android framework:</p>
4317
4318<ul>
4319 <li>MUST maintain compatibility with existing applications.</li>
4320 <li>MUST NOT have a visible user interface when a security violation is detected
4321and successfully blocked, but MAY have a visible user interface when an
4322unblocked security violation occurs resulting in a successful exploit.</li>
4323 <li>SHOULD NOT be user or developer configurable.</li>
4324</ul>
4325
4326<p>If any API for configuration of policy is exposed to an application that can
4327affect another application (such as a Device Administration API), the API MUST
4328NOT allow configurations that break compatibility.</p>
4329
4330<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4331if using a kernel other than Linux and meet the following requirements, which
4332are satisfied by the reference implementation in the upstream Android Open
4333Source Project.</p>
4334
4335<p>Device implementations:</p>
4336
4337<ul>
4338 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4339per-domain basis, and MUST configure all domains in enforcing mode. No
4340permissive mode domains are allowed, including domains specific to a
4341device/vendor.</li>
4342 <li>SHOULD load policy from /sepolicy file on the device.</li>
4343 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4344sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4345the policy MUST compile with all neverallow present, for both AOSP SELinux
4346domains as well as device/vendor specific domains.</li>
4347 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4348system image update.</li>
4349</ul>
4350
4351<p>Device implementations SHOULD retain the default SELinux policy provided in the
4352upstream Android Open Source Project, until they have first audited their
4353additions to the SELinux policy. Device implementations MUST be compatible with
4354the upstream Android Open Source Project.</p>
4355
4356<h2 id="9_8_privacy">9.8. Privacy</h2>
4357
4358<p>If the device implements functionality in the system that captures the contents
4359displayed on the screen and/or records the audio stream played on the device,
4360it MUST continuously notify the user whenever this functionality is enabled and
4361actively capturing/recording.</p>
4362
4363<p>If a device implementation has a mechanism that routes network data traffic
4364through a proxy server or VPN gateway by default (for example, preloading a VPN
4365service with android.permission.CONTROL_VPN granted), the device implementation
4366MUST ask for the user's consent before enabling that mechanism.</p>
4367
Unsuk Jungaad25192015-09-29 11:55:45 -0700[diff] [blame]4368<p>If a device implementation has a USB port with USB peripheral mode support,
4369it MUST present a user interface asking for the user's consent before allowing
4370access to the contents of the shared storage over the USB port.</p>
4371
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4372<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4373
4374<div class="note">
4375<p>Optional for Android device implementations without a lock screen.</p>
4376</div>
4377
4378
4379<p>If the device implementation supports a lock screen with PIN (numeric) or
4380PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4381application private data (/data partition), as well
4382as the SD card partition if it is a permanent, non-removable part of the device
4383[<a href="http://source.android.com/devices/tech/security/encryption/index.html">Resources, 107</a>]. For devices supporting full-disk encryption, the full-disk encryption SHOULD
4384be enabled all the time after the user has completed the out-of-box experience.
4385While this requirement is stated as SHOULD for this version of the Android
4386platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4387Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4388for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4389be written to storage at any time without being encrypted. Other than when in
4390active use, the encryption key SHOULD be AES encrypted with the lockscreen
4391passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4392If the user has not specified a lockscreen passcode or has disabled use of the
4393passcode for encryption, the system SHOULD use a default passcode to wrap the
4394encryption key. If the device provides a hardware-backed keystore, the password
4395stretching algorithm MUST be cryptographically bound to that keystore. The
4396encryption key MUST NOT be sent off the device (even when wrapped with the user
4397passcode and/or hardware bound key). The upstream Android Open Source project
Clay Murphyf4fa6bc2015-08-28 17:20:31 -0700[diff] [blame]4398provides a preferred implementation of this feature based on the Linux kernel
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4399feature dm-crypt.</p>
4400
4401<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4402
4403<p>
4404Verified boot is a feature that guarantees the integrity of the device software.
4405If a device implementation supports the feature, it MUST:
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4406</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4407<ul>
4408<li>Declare the platform feature flag android.software.verified_boot</li>
4409<li>Perform verification on every boot sequence</li>
Clay Murphyf4fa6bc2015-08-28 17:20:31 -0700[diff] [blame]4410<li>Start verification from an immutable hardware key that is the root of trust,
4411and go all the way up to the system partition</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4412<li>Implement each stage of verification to check the integrity and authenticity
4413of all the bytes in the next stage before executing the code in the next stage</li>
4414<li>Use verification algorithms as strong as current recommendations
4415from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4416</ul>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4417
Clay Murphyf4fa6bc2015-08-28 17:20:31 -0700[diff] [blame]4418<p>The upstream Android Open Source Project provides a preferred implementation of this
4419feature based on the Linux kernel feature dm-verity.</p>
4420
4421<p>Starting from Android 6.0, device implementations with Advanced Encryption Standard (AES)
4422crypto perfomance above 50MiB/seconds MUST support verified boot for device integrity.
4423If a device implementation is already launched without supporting verified boot on an earlier
4424version of Android, such a device can not add support for this feature with a system software
4425update and thus are exempted from the requirement.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4426
4427<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4428
4429
4430<p>Device implementations MUST pass all tests described in this section.</p>
4431
4432<p>However, note that no software test package is fully comprehensive. For this
Bert McMeen816a2422015-09-29 16:33:19 -0700[diff] [blame]4433reason, device implementers are <strong>STRONGLY RECOMMENDED</strong> to make the minimum number of changes as possible to the reference and
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4434preferred implementation of Android available from the Android Open Source
4435Project. This will minimize the risk of introducing bugs that create
4436incompatibilities requiring rework and potential device updates.</p>
4437
4438<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4439
4440
4441<p>Device implementations MUST pass the Android Compatibility Test Suite (CTS) [<a href="http://source.android.com/compatibility/index.html">Resources, 108</a>] available from the Android Open Source Project, using the final shipping
4442software on the device. Additionally, device implementers SHOULD use the
4443reference implementation in the Android Open Source tree as much as possible,
4444and MUST ensure compatibility in cases of ambiguity in CTS and for any
4445reimplementations of parts of the reference source code.</p>
4446
4447<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4448may itself contain bugs. The CTS will be versioned independently of this
4449Compatibility Definition, and multiple revisions of the CTS may be released for
4450Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4451at the time the device software is completed.</p>
4452
4453<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4454
4455
4456<p>Device implementations MUST correctly execute all applicable cases in the CTS
4457Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4458is intended to be run by a human operator to test functionality that cannot be
4459tested by an automated system, such as correct functioning of a camera and
4460sensors.</p>
4461
4462<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4463that is optional. Device implementations MUST pass all tests for hardware that
4464they possess; for instance, if a device possesses an accelerometer, it MUST
4465correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4466for features noted as optional by this Compatibility Definition Document MAY be
4467skipped or omitted.</p>
4468
4469<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4470above. However, since many builds are very similar, device implementers are not
4471expected to explicitly run the CTS Verifier on builds that differ only in
4472trivial ways. Specifically, device implementations that differ from an
4473implementation that has passed the CTS Verifier only by the set of included
4474locales, branding, etc. MAY omit the CTS Verifier test.</p>
4475
4476<h1 id="11_updatable_software">11. Updatable Software</h1>
4477
4478
4479<p>Device implementations MUST include a mechanism to replace the entirety of the
4480system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4481device restart MAY be required.</p>
4482
4483<p>Any method can be used, provided that it can replace the entirety of the
4484software preinstalled on the device. For instance, any of the following
4485approaches will satisfy this requirement:</p>
4486
4487<ul>
4488 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4489 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4490 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4491</ul>
4492
4493<p>However, if the device implementation includes support for an unmetered data
4494connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4495
4496<ul>
4497<li>Android Automotive implementations SHOULD support OTA downloads with offline
4498update via reboot.</li>
4499<li>All other device implementations MUST support OTA downloads with offline
4500update via reboot.</li>
4501</ul>
4502
4503<p>The update mechanism used MUST support updates without wiping user data. That
4504is, the update mechanism MUST preserve application private data and application
4505shared data. Note that the upstream Android software includes an update
4506mechanism that satisfies this requirement.</p>
4507
4508<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4509update mechanism SHOULD support verifying that the system image is binary
4510identical to expected result following an OTA. The block-based OTA
4511implementation in the upstream Android Open Source Project, added since Android
45125.1, satisfies this requirement.</p>
4513
4514<p>If an error is found in a device implementation after it has been released but
4515within its reasonable product lifetime that is determined in consultation with
4516the Android Compatibility Team to affect the compatibility of third-party
4517applications, the device implementer MUST correct the error via a software
4518update available that can be applied per the mechanism just described.</p>
4519
4520<h1 id="12_document_changelog">12. Document Changelog</h1>
4521
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4522<p>The following table contains a summary of the changes to the Compatibility
4523Definition in this release. </p>
4524<table>
4525 <tr>
4526 <th>Section</th>
4527 <th>Summary of change</th>
4528 </tr>
4529 <tr>
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]4530 <td>text</td>
4531 <td>text</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4532 </tr>
Bert McMeen15ecb402015-10-01 13:17:55 -0700[diff] [blame]4533 </table>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4534
4535
4536<h1 id="13_contact_us">13. Contact Us</h1>
4537
4538
4539<p>You can join the android-compatibility forum <a href="https://groups.google.com/forum/#!forum/android-compatibility">[Resources, 109</a>] and ask for clarifications or bring up any issues that you think the document
4540does not cover.</p>
4541
4542<h1 id="14_resources">14. Resources</h1>
4543
4544
4545<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4546
4547<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4548
4549<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>
4550
4551<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>
4552
4553<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4554
4555<p>6. 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>
4556
4557<p>7. 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>
4558
4559<p>8. Android ANDROID_VERSION allowed version strings: <a href="http://source.android.com/compatibility/ANDROID_VERSION/versions.html">http://source.android.com/compatibility/ANDROID_VERSION/versions.html</a></p>
4560
4561<p>9. Telephony Provider: <a href="http://developer.android.com/reference/android/provider/Telephony.html">http://developer.android.com/reference/android/provider/Telephony.html</a></p>
4562
4563<p>10. 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>
4564
4565<p>11. 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>
4566
4567<p>12. 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>
4568
4569<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4570
4571<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4572
4573<p>15. 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>
4574
4575<p>16. 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>
4576
4577<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4578
4579<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4580
4581<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4582
4583<p>20. Dalvik Executable Format and bytecode specification: available in the
4584Android source code, at dalvik/docs</p>
4585
4586<p>21. 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>
4587
4588<p>22. 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>
4589
4590<p>23. 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>
4591
4592<p>24. 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>
4593
4594<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4595
4596<p>26. Search Manager: <a href="http://developer.android.com/reference/android/app/SearchManager.html">http://developer.android.com/reference/android/app/SearchManager.html</a> </p>
4597
4598<p>27. Toasts: <a href="http://developer.android.com/reference/android/widget/Toast.html">http://developer.android.com/reference/android/widget/Toast.html</a></p>
4599
4600<p>28. Themes: <a href="http://developer.android.com/guide/topics/ui/themes.html">http://developer.android.com/guide/topics/ui/themes.html</a></p>
4601
4602<p>29. 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>
4603
4604<p>30. 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>
4605
4606<p>31. 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>
4607
4608<p>32. Overview screen resources: <a href="http://developer.android.com/guide/components/recents.html">http://developer.android.com/guide/components/recents.html</a> </p>
4609
4610<p>33. 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>
4611
4612<p>34. 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>
4613
4614<p>35. 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>
4615
4616<p>36. 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>
4617
4618<p>37. Settings.Secure LOCATION_MODE:</p>
4619
4620<p><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>
4621
4622<p>38. Unicode 6.1.0: <a href="http://www.unicode.org/versions/Unicode6.1.0/">http://www.unicode.org/versions/Unicode6.1.0/</a></p>
4623
4624<p>39. 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>
4625
4626<p>40. 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>
4627
4628<p>41. Android Device Owner App:</p>
4629
4630<p><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>
Andy Dyer-smith3d24bbe2015-09-11 15:35:23 +0100[diff] [blame]4631<p>XX. Android Device Owner Provisioning Flow:</p>
4632
4633<p><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>
4634<p>XX. Device Owner Provisioning via NFC:</p>
4635
4636<p><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>
4637<p>XX. Android Managed Profile Provisioning flow:</p>
4638
4639<p><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>
4640
4641<p>XX. Android Profile Owner App:</p>
4642
4643<p><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>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4644
4645<p>42. 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>
4646
4647<p>43. 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>
4648
4649<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4650
4651<p>45. 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>
4652
4653<p>46. Television Input Framework: <a href="https://source.android.com/devices/tv/index.html">https://source.android.com/devices/tv/index.html</a></p>
4654
4655<p>47. 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>
4656
4657<p>48. Android apk file description: <a href="http://developer.android.com/guide/components/fundamentals.html">http://developer.android.com/guide/components/fundamentals.html </a></p>
4658
4659<p>49. 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>
4660
4661<p>50. 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>
4662
4663<p>51. RTC Hardware Coding Requirements: <a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">http://www.webmproject.org/hardware/rtc-coding-requirements/</a></p>
4664
4665<p>52. 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>
4666
4667<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4668
4669<p><a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">http://developer.android.com/reference/android/content/pm/PackageManager.html</a></p>
4670
4671<p>54. 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>
4672
4673<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4674
4675<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4676
4677<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4678
4679<p>58. Monkey testing tool: <a href="http://developer.android.com/tools/help/monkey.html">http://developer.android.com/tools/help/monkey.html</a> </p>
4680
4681<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4682
4683<p>60. Android Application Development-Related Settings:</p>
4684
4685<p><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>
4686
4687<p>61. 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>
4688
4689<p>62. 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>
4690
4691<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4692
4693<p>64. 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>
4694
4695<p>65. 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>
4696
4697<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4698
4699<p><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>
4700
4701<p>67. 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>
4702
4703<p>68. 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>
4704
4705<p>69. 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>
4706
4707<p>70. 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>
4708
4709<p>71. 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>
4710
4711<p>72. 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>
4712
4713<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4714
4715<p>74. 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>
4716
4717<p>75. 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>
4718
4719<p>76. 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>
4720
4721<p>77. 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>
4722
4723<p>78. 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>
4724
4725<p>79. 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>
4726
4727<p>80. 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>
4728
4729<p>81. 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>
4730
4731<p>82. 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>
4732
4733<p>83. 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>
4734
4735<p>84. 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>
4736
4737<p>85. 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>
4738
4739<p>86. Android NFC Sharing Settings:</p>
4740
4741<p><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>
4742
4743<p>87. 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>
4744
4745<p>88. 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>
4746
4747<p>89. Content Resolver: <a href="http://developer.android.com/reference/android/content/ContentResolver.html">http://developer.android.com/reference/android/content/ContentResolver.html</a></p>
4748
4749<p>90. 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>
4750
4751<p>91. Camera: <a href="http://developer.android.com/reference/android/hardware/Camera.html">http://developer.android.com/reference/android/hardware/Camera.html</a></p>
4752
4753<p>92. 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>
4754
4755<p>93. 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>
4756
4757<p>94. Camera version support: <a href="http://source.android.com/devices/camera/versioning.html">http://source.android.com/devices/camera/versioning.html</a> </p>
4758
4759<p>95. Android DownloadManager: <a href="http://developer.android.com/reference/android/app/DownloadManager.html">http://developer.android.com/reference/android/app/DownloadManager.html</a></p>
4760
4761<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4762
4763<p>97. 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>
4764
4765<p>98. 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>
4766
4767<p>99. 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>
4768
4769<p>100. 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>
4770
4771<p>101. Wired audio headset: <a href="http://source.android.com/accessories/headset-spec.html">http://source.android.com/accessories/headset-spec.html</a> </p>
4772
4773<p>102. 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>
4774
4775<p>103. UserManager reference: <a href="http://developer.android.com/reference/android/os/UserManager.html">http://developer.android.com/reference/android/os/UserManager.html</a></p>
4776
4777<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4778
4779<p>105. 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>
4780
4781<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4782
4783<p>107. 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>
4784
4785<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4786
4787<p>109. Android Compatibility forum: <a href="https://groups.google.com/forum/#!forum/android-compatibility">https://groups.google.com/forum/#!forum/android-compatibility</a></p>
4788
4789<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4790
4791<p>111. 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>
4792
4793<p>112. 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>
4794
4795<p>113. 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>
4796
4797<p>Many of these resources are derived directly or indirectly from the Android
4798SDK, and will be functionally identical to the information in that SDK&rsquo;s
4799documentation. In any cases where this Compatibility Definition or the
4800Compatibility Test Suite disagrees with the SDK documentation, the SDK
4801documentation is considered authoritative. Any technical details provided in
4802the references included above are considered by inclusion to be part of this
4803Compatibility Definition.</p>
4804
4805</div>
4806</body>
4807</html>