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Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1<!DOCTYPE html>
2<head>
3<title>Android ANDROID_VERSION Compatibility Definition</title>
4<link rel="stylesheet" type="text/css" href="android-cdd.css"/>
5</head>
6
7<body>
8
9<h6>Table of Contents</h6>
10
11<div id="toc">
12
13<div id="toc_left">
14
15<p class="toc_h1"><a href="#1_introduction">1. Introduction</a></p>
16
17<p class="toc_h1"><a href="#2_device_types">2. Device Types</a></p>
18
19<p class="toc_h2"><a href="#2_1_device_configurations">2.1 Device Configurations</a></p>
20
21<p class="toc_h1"><a href="#3_software">3. Software</a></p>
22
23<p class="toc_h2"><a href="#3_1_managed_api_compatibility">3.1. Managed API Compatibility</a></p>
24
25<p class="toc_h2"><a href="#3_2_soft_api_compatibility">3.2. Soft API Compatibility</a></p>
26
27<p class="toc_h3"><a href="#3_2_1_permissions">3.2.1. Permissions</a></p>
28
29<p class="toc_h3"><a href="#3_2_2_build_parameters">3.2.2. Build Parameters</a></p>
30
31<p class="toc_h3"><a href="#3_2_3_intent_compatibility">3.2.3. Intent Compatibility</a></p>
32
33<p class="toc_h4"><a href="#3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</a></p>
34
35<p class="toc_h4"><a href="#3_2_3_2_intent_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
83<p class="toc_h3"><a href="#3_8_11_dreams">3.8.11. Dreams</a></p>
84
85<p class="toc_h3"><a href="#3_8_12_location">3.8.12. Location</a></p>
86
87<p class="toc_h3"><a href="#3_8_13_unicode_and_font">3.8.13. Unicode and Font</a></p>
88
89
90
91</div>
92
93<div id="toc_right"><br>
94
95
96
97<p class="toc_h2"><a href="#3_9_device_administration">3.9. Device Administration</a></p>
98
99<p class="toc_h2"><a href="#3_10_accessibility">3.10. Accessibility</a></p>
100
101<p class="toc_h2"><a href="#3_11_text-to-speech">3.11. Text-to-Speech</a></p>
102
103<p class="toc_h2"><a href="#3_12_tv_input_framework">3.12. TV Input Framework</a></p>
104
105<p class="toc_h1"><a href="#4_application_packaging_compatibility">4. Application Packaging Compatibility</a></p>
106
107<p class="toc_h1"><a href="#5_multimedia_compatibility">5. Multimedia Compatibility</a></p>
108
109<p class="toc_h2"><a href="#5_1_media_codecs">5.1. Media Codecs</a></p>
110
111<p class="toc_h3"><a href="#5_1_1_audio_codecs">5.1.1. Audio Codecs</a></p>
112
113<p class="toc_h3"><a href="#5_1_2_image_codecs">5.1.2. Image Codecs</a></p>
114
115<p class="toc_h3"><a href="#5_1_3_video_codecs">5.1.3. Video Codecs</a></p>
116
117<p class="toc_h2"><a href="#5_2_video_encoding">5.2. Video Encoding</a></p>
118
119<p class="toc_h2"><a href="#5_3_video_decoding">5.3. Video Decoding</a></p>
120
121<p class="toc_h2"><a href="#5_4_audio_recording">5.4. Audio Recording</a></p>
122
123<p class="toc_h3"><a href="#5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</a></p>
124
125<p class="toc_h3"><a href="#5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</a></p>
126
127<p class="toc_h3"><a href="#5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</a></p>
128
129<p class="toc_h2"><a href="#5_5_audio_playback">5.5. Audio Playback</a></p>
130
131<p class="toc_h3"><a href="#5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</a></p>
132
133<p class="toc_h3"><a href="#5_5_2_audio_effects">5.5.2. Audio Effects</a></p>
134
135<p class="toc_h3"><a href="#5_5_3_audio_output_volume">5.5.3. Audio Output Volume</a></p>
136
137<p class="toc_h2"><a href="#5_6_audio_latency">5.6. Audio Latency</a></p>
138
139<p class="toc_h2"><a href="#5_7_network_protocols">5.7. Network Protocols</a></p>
140
141<p class="toc_h2"><a href="#5_8_secure_media">5.8. Secure Media</a></p>
142
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]143<p class="toc_h2"><a href="#5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</a></p>
144
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame^]145<p class="toc_h2"><a href="#5_10_pro_audio">5.10. Professional Audio</a></p>
146
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]147<p class="toc_h1"><a href="#6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</a></p>
148
149<p class="toc_h2"><a href="#6_1_developer_tools">6.1. Developer Tools</a></p>
150
151<p class="toc_h2"><a href="#6_2_developer_options">6.2. Developer Options</a></p>
152
153<p class="toc_h1"><a href="#7_hardware_compatibility">7. Hardware Compatibility</a></p>
154
155<p class="toc_h2"><a href="#7_1_display_and_graphics">7.1. Display and Graphics</a></p>
156
157<p class="toc_h3"><a href="#7_1_1_screen_configuration">7.1.1. Screen Configuration</a></p>
158
159<p class="toc_h4"><a href="#7_1_1_1_screen_size">7.1.1.1. Screen Size</a></p>
160
161<p class="toc_h4"><a href="#7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</a></p>
162
163<p class="toc_h4"><a href="#7_1_1_3_screen_density">7.1.1.3. Screen Density</a></p>
164
165
166</div>
167
168<div style="clear: both; page-break-after:always; height:1px"></div>
169
170
171<div id="toc_left_2">
172
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
211<p class="toc_h3"><a href="#7_3_4_gyroscope">7.3.4. Gyroscope</a></p>
212
213<p class="toc_h3"><a href="#7_3_5_barometer">7.3.5. Barometer</a></p>
214
215<p class="toc_h3"><a href="#7_3_6_thermometer">7.3.6. Thermometer</a></p>
216
217<p class="toc_h3"><a href="#7_3_7_photometer">7.3.7. Photometer</a></p>
218
219<p class="toc_h3"><a href="#7_3_8_proximity_sensor">7.3.8. Proximity Sensor</a></p>
220
221<p class="toc_h2"><a href="#7_4_data_connectivity">7.4. Data Connectivity</a></p>
222
223<p class="toc_h3"><a href="#7_4_1_telephony">7.4.1. Telephony</a></p>
224
225<p class="toc_h3"><a href="#7_4_2_ieee_80211_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
226
227<p class="toc_h4"><a href="#7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</a></p>
228
229<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>
230
231<p class="toc_h3"><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></p>
232
233<p class="toc_h3"><a href="#7_4_4_near-field_communications">7.4.4. Near-Field Communications</a></p>
234
235<p class="toc_h3"><a href="#7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</a></p>
236
237<p class="toc_h3"><a href="#7_4_6_sync_settings">7.4.6. Sync Settings</a></p>
238
239<p class="toc_h2"><a href="#7_5_cameras">7.5. Cameras</a></p>
240
241<p class="toc_h3"><a href="#7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</a></p>
242
243<p class="toc_h3"><a href="#7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</a></p>
244
245<p class="toc_h3"><a href="#7_5_3_external_camera">7.5.3. External Camera</a></p>
246
247<p class="toc_h3"><a href="#7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</a></p>
248
249
250
251
252
253</div>
254
255<div id="toc_right_2">
256
257<p class="toc_h3"><a href="#7_5_5_camera_orientation">7.5.5. Camera Orientation</a></p>
258
259<p class="toc_h2"><a href="#7_6_memory_and_storage">7.6. Memory and Storage</a></p>
260
261<p class="toc_h3"><a href="#7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</a></p>
262
263<p class="toc_h3"><a href="#7_6_2_application_shared_storage">7.6.2. Application Shared Storage</a></p>
264
265<p class="toc_h2"><a href="#7_7_usb">7.7. USB</a></p>
266
267<p class="toc_h2"><a href="#7_8_audio">7.8. Audio</a></p>
268
269<p class="toc_h3"><a href="#7_8_1_microphone">7.8.1. Microphone</a></p>
270
271<p class="toc_h3"><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></p>
272
273<p class="toc_h4"><a href="#7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</a></p>
274
275<p class="toc_h1"><a href="#8_performance_compatibility">8. Performance Compatibility</a></p>
276
277<p class="toc_h2"><a href="#8_1_user_experience_consistency">8.1. User Experience Consistency</a></p>
278
279<p class="toc_h2"><a href="#8_2_memory_performance">8.2. Memory Performance</a></p>
280
281<p class="toc_h1"><a href="#9_security_model_compatibility">9. Security Model Compatibility</a></p>
282
283<p class="toc_h2"><a href="#9_1_permissions">9.1. Permissions</a></p>
284
285<p class="toc_h2"><a href="#9_2_uid_and_process_isolation">9.2. UID and Process Isolation</a></p>
286
287<p class="toc_h2"><a href="#9_3_filesystem_permissions">9.3. Filesystem Permissions</a></p>
288
289<p class="toc_h2"><a href="#9_4_alternate_execution_environments">9.4. Alternate Execution Environments</a></p>
290
291<p class="toc_h2"><a href="#9_5_multi-user_support">9.5. Multi-User Support</a></p>
292
293<p class="toc_h2"><a href="#9_6_premium_sms_warning">9.6. Premium SMS Warning</a></p>
294
295<p class="toc_h2"><a href="#9_7_kernel_security_features">9.7. Kernel Security Features</a></p>
296
297<p class="toc_h2"><a href="#9_8_privacy">9.8. Privacy</a></p>
298
299<p class="toc_h2"><a href="#9_9_full-disk-encryption">9.9. Full-Disk Encryption</a></p>
300
301<p class="toc_h2"><a href="#9_10_verified_boot">9.10. Verified Boot</a></p>
302
303<p class="toc_h1"><a href="#10_software_compatibility_testing">10. Software Compatibility Testing</a></p>
304
305<p class="toc_h2"><a href="#10_1_compatibility_test_suite">10.1. Compatibility Test Suite</a></p>
306
307<p class="toc_h2"><a href="#10_2_cts_verifier">10.2. CTS Verifier</a></p>
308
309<p class="toc_h1"><a href="#11_updatable_software">11. Updatable Software</a></p>
310
311<p class="toc_h1"><a href="#12_document_changelog">12. Document Changelog</a></p>
312
313<p class="toc_h1"><a href="#13_contact_us">13. Contact Us</a></p>
314
315<p class="toc_h1"><a href="#14_resources">14. Resources</a></p>
316
317</div>
318
319</div>
320
321<div style="clear: both"></div>
322
323<div id="main">
324
325<h1 id="1_introduction">1. Introduction</h1>
326
327
328<p>This document enumerates the requirements that must be met in order for devices
329to be compatible with Android ANDROID_VERSION.</p>
330
331<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
332defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
333
334<p>As used in this document, a &ldquo;device implementer&rdquo; or &ldquo;implementer&rdquo; is a person
335or organization developing a hardware/software solution running Android ANDROID_VERSION. A
336&ldquo;device implementation&rdquo; or &ldquo;implementation is the hardware/software solution
337so developed.</p>
338
339<p>To be considered compatible with Android ANDROID_VERSION, device implementations MUST meet
340the requirements presented in this Compatibility Definition, including any
341documents incorporated via reference.</p>
342
343<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
344implementer to ensure compatibility with existing implementations.</p>
345
346<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
347implementers are strongly encouraged to base their implementations to the
348greatest extent possible on the &ldquo;upstream&rdquo; source code available from the
349Android Open Source Project. While some components can hypothetically be
350replaced with alternate implementations this practice is strongly discouraged,
351as passing the software tests will become substantially more difficult. It is
352the implementer&rsquo;s responsibility to ensure full behavioral compatibility with
353the standard Android implementation, including and beyond the Compatibility
354Test Suite. Finally, note that certain component substitutions and
355modifications are explicitly forbidden by this document.</p>
356
357<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
358functionally identical to the information in that SDK&rsquo;s documentation. For any
359case where this Compatibility Definition or the Compatibility Test Suite
360disagrees with the SDK documentation, the SDK documentation is considered
361authoritative. 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>
362
363<h1 id="2_device_types">2. Device Types</h1>
364
365
366<p>While the Android Open Source Project has been used in the implementation of a
367variety of device types and form factors, many aspects of the architecture and
368compatibility requirements were optimized for handheld devices. Starting from
369Android 5.0, the Android Open Source Project aims to embrace a wider variety of
370device types as described in this section.</p>
371
372<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
373it in the hand, such as mp3 players, phones, and tablets. Android Handheld
374device implementations:</p>
375
376<ul>
377 <li>MUST have a touchscreen embedded in the device.</li>
378 <li>MUST have a power source that provides mobility, such as a battery.</li>
379</ul>
380
381<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
382for consuming digital media, movies, games, apps, and/or live TV for users
383sitting about ten feet away (a &ldquo;lean back&rdquo; or &ldquo;10-foot user interface&rdquo;).
384Android Television devices:</p>
385
386<ul>
387 <li>MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
388or a wireless port for display.</li>
389 <li>MUST declare the features android.software.leanback and
390android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>].</li>
391</ul>
392
393<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
394perhaps on the wrist, and:</p>
395
396<ul>
397 <li>MUST have a screen with the physical diagonal length in the range from 1.1 to
3982.5 inches.</li>
399 <li>MUST declare the feature android.hardware.type.watch.</li>
400 <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>
401</ul>
402
403<p><strong>Android Automotive implementation</strong> refers to a vehicle head
404unit running Android as an operating system for part or all of the system and/or
405infotainment functionality. Android Automotive implementations MUST support
406uiMode = UI_MODE_TYPE_CAR [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">Resources, 111</a>].</p>
407
408<p>All Android device implementations that do not fit into any of the above device
409types still MUST meet all requirements in this document to be Android ANDROID_VERSION
410compatible, unless the requirement is explicitly described to be only
411applicable to a specific Android device type from above.</p>
412
413<h2 id="2_1_device_configurations">2.1 Device Configurations</h2>
414
415
416<p>This is a summary of major differences in hardware configuration by device
417type. (Empty cells denote a &ldquo;MAY&rdquo;). Not all configurations are covered in this
418table; see relevant hardware sections for more detail.</p>
419<table>
420 <tr>
421 <th>Category</th>
422 <th>Feature</th>
423 <th>Section</th>
424 <th>Handheld</th>
425 <th>Television</th>
426 <th>Watch</th>
427 <th>Automotive</th>
428 <th>Other</th>
429 </tr>
430 <tr>
431 <td rowspan="3">Input</td>
432 <td>D-pad</td>
433 <td><a href="#7_2_2_non-touch-navigation">7.2.2. Non-touch Navigation</a></td>
434 <td></td>
435 <td>MUST</td>
436 <td></td>
437 <td></td>
438 <td></td>
439 </tr>
440 <tr>
441 <td>Touchscreen </td>
442 <td><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen input</a></td>
443 <td>MUST</td>
444 <td></td>
445 <td>MUST</td>
446 <td></td>
447 <td>SHOULD</td>
448 </tr>
449 <tr>
450 <td>Microphone </td>
451 <td><a href="#7_8_1_microphone">7.8.1. Microphone</a></td>
452 <td>MUST</td>
453 <td>SHOULD </td>
454 <td>MUST</td>
455 <td>MUST</td>
456 <td>SHOULD</td>
457 </tr>
458 <tr>
459 <td rowspan="2">Sensors</td>
460 <td>Accelerometer </td>
461 <td><a href="#7_3_1_accelerometer">7.3.1 Accelerometer</a></td>
462 <td>SHOULD</td>
463 <td></td>
464 <td>SHOULD</td>
465 <td></td>
466 <td>SHOULD</td>
467 </tr>
468 <tr>
469 <td>GPS</td>
470 <td><a href="#7_3_3_gps">7.3.3. GPS</a></td>
471 <td>SHOULD</td>
472 <td></td>
473 <td></td>
474 <td>SHOULD</td>
475 <td></td>
476 </tr>
477 <tr>
478 <td rowspan="5">Connectivity</td>
479 <td>Wi-Fi</td>
480 <td><a href="#7_4_2_ieee_802.11">7.4.2. IEEE 802.11</a></td>
481 <td>SHOULD</td>
482 <td> MUST</td>
483 <td></td>
484 <td>SHOULD</td>
485 <td>SHOULD</td>
486 </tr>
487 <tr>
488 <td>Wi-Fi Direct</td>
489 <td><a href="#7_4_2_1_wi-fi-direct">7.4.2.1. Wi-Fi Direct</a></td>
490 <td>SHOULD</td>
491 <td>SHOULD</td>
492 <td></td>
493 <td></td>
494 <td>SHOULD</td>
495 </tr>
496 <tr>
497 <td>Bluetooth</td>
498 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
499 <td>SHOULD</td>
500 <td>MUST</td>
501 <td>MUST</td>
502 <td>MUST</td>
503 <td>SHOULD</td>
504 </tr>
505 <tr>
506 <td>Bluetooth Low Energy</td>
507 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
508 <td>SHOULD</td>
509 <td>MUST</td>
510 <td>SHOULD</td>
511 <td>SHOULD</td>
512 <td>SHOULD</td>
513 </tr>
514 <tr>
515 <td>USB peripheral/host mode</td>
516 <td><a href="#7_7_usb">7.7. USB</a></td>
517 <td>SHOULD</td>
518 <td></td>
519 <td></td>
520 <td>SHOULD</td>
521 <td>SHOULD</td>
522 </tr>
523 <tr>
524 <td>Output</td>
525 <td>Speaker and/or Audio output ports</td>
526 <td><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></td>
527 <td>MUST</td>
528 <td>MUST</td>
529 <td></td>
530 <td>MUST</td>
531 <td>MUST</td>
532 </tr>
533</table>
534
535
536<h1 id="3_software">3. Software</h1>
537
538
539<h2 id="3_1_managed_api_compatibility">3.1. Managed API Compatibility</h2>
540
541
542<p>The managed Dalvik bytecode execution environment is the primary vehicle for
543Android applications. The Android application programming interface (API) is
544the set of Android platform interfaces exposed to applications running in the
545managed runtime environment. Device implementations MUST provide complete
546implementations, including all documented behaviors, of any documented API
547exposed 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
548source code. </p>
549
550<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
551signatures, deviate from the documented behavior, or include no-ops, except
552where specifically allowed by this Compatibility Definition.</p>
553
554<p>This Compatibility Definition permits some types of hardware for which Android
555includes APIs to be omitted by device implementations. In such cases, the APIs
556MUST 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>
557
558<h2 id="3_2_soft_api_compatibility">3.2. Soft API Compatibility</h2>
559
560
561<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
562such things as intents, permissions, and similar aspects of Android
563applications that cannot be enforced at application compile time.</p>
564
565<h3 id="3_2_1_permissions">3.2.1. Permissions</h3>
566
567
568<p>Device implementers MUST support and enforce all permission constants as
569documented 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>
570
571<h3 id="3_2_2_build_parameters">3.2.2. Build Parameters</h3>
572
573
574<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,
575meaningful values across device implementations, the table below includes
576additional restrictions on the formats of these values to which device
577implementations MUST conform.</p>
578<table>
579 <tr>
580 <th>Parameter</th>
581 <th>Details</th>
582 </tr>
583 <tr>
584 <td>VERSION.RELEASE</td>
585 <td>The version of the currently-executing Android system, in human-readable
586format. 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>
587 </tr>
588 <tr>
589 <td>VERSION.SDK</td>
590 <td>The version of the currently-executing Android system, in a format accessible
591to third-party application code. For Android ANDROID_VERSION, this field MUST have the
592integer value 22.</td>
593 </tr>
594 <tr>
595 <td>VERSION.SDK_INT</td>
596 <td>The version of the currently-executing Android system, in a format accessible
597to third-party application code. For Android ANDROID_VERSION, this field MUST have the
598integer value 22.</td>
599 </tr>
600 <tr>
601 <td>VERSION.INCREMENTAL</td>
602 <td>A value chosen by the device implementer designating the specific build of the
603currently-executing Android system, in human-readable format. This value MUST
604NOT be reused for different builds made available to end users. A typical use
605of this field is to indicate which build number or source-control change
606identifier was used to generate the build. There are no requirements on the
607specific format of this field, except that it MUST NOT be null or the empty
608string ("").</td>
609 </tr>
610 <tr>
611 <td>BOARD</td>
612 <td>A value chosen by the device implementer identifying the specific internal
613hardware used by the device, in human-readable format. A possible use of this
614field is to indicate the specific revision of the board powering the device.
615The value of this field MUST be encodable as 7-bit ASCII and match the regular
616expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
617 </tr>
618 <tr>
619 <td>BRAND</td>
620 <td>A value reflecting the brand name associated with the device as known to the
621end users. MUST be in human-readable format and SHOULD represent the
622manufacturer of the device or the company brand under which the device is
623marketed. The value of this field MUST be encodable as 7-bit ASCII and match
624the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
625 </tr>
626 <tr>
627 <td>SUPPORTED_ABIS</td>
628 <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>
629 </tr>
630 <tr>
631 <td>SUPPORTED_32_BIT_ABIS</td>
632 <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>
633 </tr>
634 <tr>
635 <td>SUPPORTED_64_BIT_ABIS</td>
636 <td>The name of the second instruction set (CPU type + ABI convention) of native
637code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
638 </tr>
639 <tr>
640 <td>CPU_ABI</td>
641 <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>
642 </tr>
643 <tr>
644 <td>CPU_ABI2</td>
645 <td>The name of the second instruction set (CPU type + ABI convention) of native
646code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
647 </tr>
648 <tr>
649 <td>DEVICE</td>
650 <td>A value chosen by the device implementer containing the development name or
651code name identifying the configuration of the hardware features and industrial
652design of the device. The value of this field MUST be encodable as 7-bit ASCII
653and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
654 </tr>
655 <tr>
656 <td>FINGERPRINT</td>
657 <td>A string that uniquely identifies this build. It SHOULD be reasonably
658human-readable. It MUST follow this template:</p>
659
660<p class="small">$(BRAND)/$(PRODUCT)/$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
661
662<p>For example: acme/myproduct/mydevice:ANDROID_VERSION/LMYXX/3359:userdebug/test-keys</p>
663
664<p>The fingerprint MUST NOT include whitespace characters. If other fields
665included in the template above have whitespace characters, they MUST be
666replaced in the build fingerprint with another character, such as the
667underscore ("_") character. The value of this field MUST be encodable as 7-bit
668ASCII.</td>
669 </tr>
670 <tr>
671 <td>HARDWARE</td>
672 <td>The name of the hardware (from the kernel command line or /proc). It SHOULD be
673reasonably human-readable. The value of this field MUST be encodable as 7-bit
674ASCII and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;. </td>
675 </tr>
676 <tr>
677 <td>HOST</td>
678 <td>A string that uniquely identifies the host the build was built on, in
679human-readable format. There are no requirements on the specific format of this
680field, except that it MUST NOT be null or the empty string ("").</td>
681 </tr>
682 <tr>
683 <td>ID</td>
684 <td>An identifier chosen by the device implementer to refer to a specific release,
685in human-readable format. This field can be the same as
686android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
687meaningful for end users to distinguish between software builds. The value of
688this field MUST be encodable as 7-bit ASCII and match the regular expression &ldquo;^[a-zA-Z0-9._-]+$&rdquo;.</td>
689 </tr>
690 <tr>
691 <td>MANUFACTURER</td>
692 <td>The trade name of the Original Equipment Manufacturer (OEM) of the product.
693There are no requirements on the specific format of this field, except that it
694MUST NOT be null or the empty string ("").</td>
695 </tr>
696 <tr>
697 <td>MODEL</td>
698 <td>A value chosen by the device implementer containing the name of the device as
699known to the end user. This SHOULD be the same name under which the device is
700marketed and sold to end users. There are no requirements on the specific
701format of this field, except that it MUST NOT be null or the empty string ("").</td>
702 </tr>
703 <tr>
704 <td>PRODUCT</td>
705 <td>A value chosen by the device implementer containing the development name or
706code name of the specific product (SKU) that MUST be unique within the same
707brand. MUST be human-readable, but is not necessarily intended for view by end
708users. The value of this field MUST be encodable as 7-bit ASCII and match the
709regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
710 </tr>
711 <tr>
712 <td>SERIAL</td>
713 <td>A hardware serial number, which MUST be available. The value of this field MUST
714be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
715 </tr>
716 <tr>
717 <td>TAGS</td>
718 <td>A comma-separated list of tags chosen by the device implementer that further
719distinguishes the build. This field MUST have one of the values corresponding
720to the three typical Android platform signing configurations: release-keys,
721dev-keys, test-keys. </td>
722 </tr>
723 <tr>
724 <td>TIME</td>
725 <td>A value representing the timestamp of when the build occurred.</td>
726 </tr>
727 <tr>
728 <td>TYPE</td>
729 <td>A value chosen by the device implementer specifying the runtime configuration
730of the build. This field MUST have one of the values corresponding to the three
731typical Android runtime configurations: user, userdebug, or eng.</td>
732 </tr>
733 <tr>
734 <td>USER</td>
735 <td>A name or user ID of the user (or automated user) that generated the build.
736There are no requirements on the specific format of this field, except that it
737MUST NOT be null or the empty string ("").</td>
738 </tr>
739</table>
740
741
742<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
743
744
745<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
746described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
747implementer MUST provide an Android Activity or Service that specifies a
748matching intent filter that binds to and implements correct behavior for each
749specified intent pattern.</p>
750
751<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
752
753
754<p>Android intents allow application components to request functionality from
755other Android components. The Android upstream project includes a list of
756applications considered core Android applications, which implements several
757intent patterns to perform common actions. The core Android applications are:</p>
758
759<ul>
760 <li>Desk Clock</li>
761 <li>Browser</li>
762 <li>Calendar</li>
763 <li>Contacts</li>
764 <li>Gallery</li>
765 <li>GlobalSearch</li>
766 <li>Launcher</li>
767 <li>Music</li>
768 <li>Settings</li>
769</ul>
770
771<p>Device implementations SHOULD include the core Android applications as
772appropriate but MUST include a component implementing the same intent patterns
773defined by all the &ldquo;public&rdquo; Activity or Service components of these core
774Android applications. Note that Activity or Service components are considered
775&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
776
777<h4 id="3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</h4>
778
779
780<p>As Android is an extensible platform, device implementations MUST allow each
781intent 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
782implementation allows this by default; device implementers MUST NOT attach
783special privileges to system applications' use of these intent patterns, or
784prevent third-party applications from binding to and assuming control of these
785patterns. This prohibition specifically includes but is not limited to
786disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
787multiple applications that all handle the same intent pattern.</p>
788
789<p>However, device implementations MAY provide default activities for specific URI
790patterns (eg. http://play.google.com) if the default activity provides a more
791specific filter for the data URI. For example, an intent filter specifying the
792data 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
793modify the default activity for intents.</p>
794
795<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
796
797
798<p>Device implementations MUST NOT include any Android component that honors any
799new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
800string in the android.* or com.android.* namespace. Device implementers MUST
801NOT include any Android components that honor any new intent or broadcast
802intent patterns using an ACTION, CATEGORY, or other key string in a package
803space belonging to another organization. Device implementers MUST NOT alter or
804extend 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
805and obviously associated with their own organization. This prohibition is
806analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
807
808<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
809
810
811<p>Third-party applications rely on the platform to broadcast certain intents to
812notify them of changes in the hardware or software environment.
813Android-compatible devices MUST broadcast the public broadcast intents in
814response to appropriate system events. Broadcast intents are described in the
815SDK documentation.</p>
816
817<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
818
819
820<p>Android includes settings that provide users an easy way to select their
821default applications, for example for Home screen or SMS. Where it makes sense,
822device implementations MUST provide a similar settings menu and be compatible
823with the intent filter pattern and API methods described in the SDK
824documentation as below.</p>
825
826<p>Device implementations:</p>
827
828<ul>
829 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
830settings menu for Home Screen, if the device implementation reports
831android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
832 <li>MUST provide a settings menu that will call the
833android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
834change the default SMS application, if the device implementation reports
835android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]</li>
836 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
837app settings menu for Tap and Pay, if the device implementation reports
838android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
839</ul>
840
841<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
842
843
844<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
845
846
847<p>Managed Dalvik bytecode can call into native code provided in the application
848.apk file as an ELF .so file compiled for the appropriate device hardware
849architecture. As native code is highly dependent on the underlying processor
850technology, Android defines a number of Application Binary Interfaces (ABIs) in
851the Android NDK. Device implementations MUST be compatible with one or more
852defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
853
854<p>If a device implementation includes support for an Android ABI, it:</p>
855
856<ul>
857 <li>MUST include support for code running in the managed environment to call into
858native code, using the standard Java Native Interface (JNI) semantics</li>
859 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
860the ABI) with each required library in the list below</li>
861 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
862 <li>MUST accurately report the native Application Binary Interface (ABI) supported
863by the device, via the android.os.Build.SUPPORTED_ABIS,
864android.os.Build.SUPPORTED_32_BIT_ABIS, and
865android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
866of ABIs ordered from the most to the least preferred one</li>
867 <li>MUST report, via the above parameters, only those ABIs documented in the latest
868version of the Android NDK, &ldquo;NDK Programmer&rsquo;s Guide | ABI Management&rdquo; in docs/
869directory</li>
870 <li>SHOULD be built using the source code and header files available in the
871upstream Android Open Source Project</li>
872</ul>
873
874<p>The following native code APIs MUST be available to apps that include native
875code:</p>
876
877<ul>
878 <li>libc (C library)</li>
879 <li>libm (math library)</li>
880 <li>Minimal support for C++</li>
881 <li>JNI interface</li>
882 <li>liblog (Android logging)</li>
883 <li>libz (Zlib compression)</li>
884 <li>libdl (dynamic linker)</li>
885 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
886 <li>libGLESv2.so (OpenGL ES 2.0)</li>
887 <li>libGLESv3.so (OpenGL ES 3.x)</li>
888 <li>libEGL.so (native OpenGL surface management)</li>
889 <li>libjnigraphics.so</li>
890 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
891 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
892 <li>libandroid.so (native Android activity support)</li>
893 <li>libmediandk.so (native media APIs support)</li>
894 <li>Support for OpenGL, as described below</li>
895</ul>
896
897<p>Note that future releases of the Android NDK may introduce support for
898additional ABIs. If a device implementation is not compatible with an existing
899predefined ABI, it MUST NOT report support for any ABIs at all.</p>
900
901<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
902(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
903Android 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
904symbols must be present, only the corresponding functions for OpenGL ES
905versions and extensions actually supported by the device must be fully
906implemented.</p>
907
908<p>Native code compatibility is challenging. For this reason, device implementers
909are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
910Android Open Source Project. </p>
911
912<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9133.3.2. 32-bit ARM Native Code Compatibility
914</h3>
915
916<p>The ARMv8 architecture deprecates several CPU operations, including some
917operations used in existing native code. On 64-bit ARM devices, the following
918deprecated operations MUST remain available to 32-bit native ARM code, either
919through native CPU support or through software emulation:</p>
920
921<ul>
922<li>SWP and SWPB instructions</li>
923<li>SETEND instruction</li>
924<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
925</ul>
926
927<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
928from 32-bit ARM native code. For compatibility with applications built using this
929NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
930by 32-bit ARM applications:</p>
931
932<ul>
933<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
934supported by the device</li>
935<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
936highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
937</ul>
938
939<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
940applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
941non-ARM applications.</p>
942
943<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
944
945
946<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
947
948<div class="note">
949<p>Android Watch devices MAY, but all other device implementations MUST provide
950a complete implementation of the android.webkit.Webview API.</p>
951</div>
952
953
954<p>The platform feature android.software.webview MUST be reported on any device
955that provides a complete implementation of the android.webkit.WebView API, and
956MUST NOT be reported on devices without a complete implementation of the API.
957The Android Open Source implementation uses code from the Chromium Project to
958implement 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
959rendering system, device implementers MUST use the specific upstream build of
960Chromium in the WebView implementation. Specifically:</p>
961
962<ul>
963 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
964build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
965includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
966 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]967<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]968AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
969Safari/537.36</p>
970 <ul>
971 <li>The value of the $(VERSION) string MUST be the same as the value for
972android.os.Build.VERSION.RELEASE.</li>
973 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
974 note that this is a webview</li>
975 <li>The value of the $(MODEL) string MUST be the same as the value for
976android.os.Build.MODEL.</li>
977 <li>The value of the $(BUILD) string MUST be the same as the value for
978android.os.Build.ID.</li>
979 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
980upstream Android Open Source Project.</li>
981 <li>Device implementations MAY omit Mobile in the user agent string.</li>
982 </ul></li></ul>
983
984<p>The WebView component SHOULD include support for as many HTML5 features as
985possible and if it supports the feature SHOULD conform to the HTML5
986specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
987
988<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
989
990<div class="note">
991<p>Android Television, Watch, and Android Automotive implementations MAY omit a
992browser application, but MUST support the public intent patterns as described in
993<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
994of device implementations MUST include a standalone Browser application for
995general user web browsing.</p>
996</div>
997
998<p>The standalone Browser MAY be based on a browser technology other than WebKit.
999However, even if an alternate Browser application is used, the
1000android.webkit.WebView component provided to third-party applications MUST be
1001based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1002
1003<p>Implementations MAY ship a custom user agent string in the standalone Browser
1004application.</p>
1005
1006<p>The standalone Browser application (whether based on the upstream WebKit
1007Browser application or a third-party replacement) SHOULD include support for as
1008much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1009APIs associated with HTML5:</p>
1010
1011<ul>
1012 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1013 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1014 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1015</ul>
1016
1017<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1018[<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
1019IndexedDB over webstorage, IndexedDB is expected to become a required component
1020in a future version of Android.</p>
1021
1022<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1023
1024
1025<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1026consistent with the preferred implementation of the upstream Android Open
1027Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1028
1029<ul>
1030 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1031 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1032type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1033 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1034</ul>
1035
1036<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1037significant portions of the platform for behavioral compatibility, but not all.
1038It is the responsibility of the implementer to ensure behavioral compatibility
1039with the Android Open Source Project. For this reason, device implementers
1040SHOULD use the source code available via the Android Open Source Project where
1041possible, rather than re-implement significant parts of the system.</p>
1042
1043<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1044
1045
1046<p>Android follows the package and class namespace conventions defined by the Java
1047programming language. To ensure compatibility with third-party applications,
1048device implementers MUST NOT make any prohibited modifications (see below) to
1049these package namespaces:</p>
1050
1051<ul>
1052 <li>java.*</li>
1053 <li>javax.*</li>
1054 <li>sun.*</li>
1055 <li>android.*</li>
1056 <li>com.android.*</li>
1057</ul>
1058
1059<p><strong>Prohibited modifications include</strong>:</p>
1060
1061<ul>
1062 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1063platform by changing any method or class signatures, or by removing classes or
1064class fields.</li>
1065 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1066such modifications MUST NOT impact the stated behavior and Java-language
1067signature of any publicly exposed APIs.</li>
1068 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1069or interfaces, or fields or methods to existing classes or interfaces) to the
1070APIs above.</li>
1071</ul>
1072
1073<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,
1074device implementers MUST NOT expose new APIs or alter existing APIs in the
1075namespaces noted above. Device implementers MAY make internal-only
1076modifications, but those modifications MUST NOT be advertised or otherwise
1077exposed to developers.</p>
1078
1079<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1080namespace owned by or referring to another organization. For instance, device
1081implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1082Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1083namespaces. Additionally, if a device implementation includes custom APIs
1084outside the standard Android namespace, those APIs MUST be packaged in an
1085Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1086lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1087APIs.</p>
1088
1089<p>If a device implementer proposes to improve one of the package namespaces above
1090(such as by adding useful new functionality to an existing API, or adding a new
1091API), 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
1092information on that site.</p>
1093
1094<p>Note that the restrictions above correspond to standard conventions for naming
1095APIs in the Java programming language; this section simply aims to reinforce
1096those conventions and make them binding through inclusion in this Compatibility
1097Definition.</p>
1098
1099<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1100
1101
1102<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1103Dalvik 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
1104the Dalvik Executable Format, and the reference implementation&rsquo;s package
1105management system.</p>
1106
1107<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1108accordance with the upstream Android platform, and as specified by the
1109following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1110
1111<p>Note that memory values specified below are considered minimum values and
1112device implementations MAY allocate more memory per application.</p>
1113
1114<table>
1115 <tr>
1116 <th>Screen Layout</th>
1117 <th>Screen Density</th>
1118 <th>Minimum Application Memory</th>
1119 </tr>
1120 <tr>
1121 <td rowspan="10">small/normal</td>
1122 <td>120 dpi (ldpi)</td>
1123 <td rowspan="2">32MB</td>
1124 </tr>
1125 <tr>
1126 <td>160 dpi (mdpi)</td>
1127 </tr>
1128 <tr>
1129 <td>213 dpi (tvdpi)</td>
1130 <td rowspan="3">48MB</td>
1131 </tr>
1132 <tr>
1133 <td>240 dpi (hdpi)</td>
1134 </tr>
1135 <tr>
1136 <td>280 dpi (280dpi)</td>
1137 </tr>
1138 <tr>
1139 <td>320 dpi (xhdpi)</td>
1140 <td>80MB</td>
1141 </tr>
1142 <tr>
1143 <td>400 dpi (400dpi)</td>
1144 <td>96MB</td>
1145 </tr>
1146 <tr>
1147 <td>480 dpi (xxhdpi)</td>
1148 <td>128MB</td>
1149 </tr>
1150 <tr>
1151 <td>560 dpi (560dpi)</td>
1152 <td>192MB</td>
1153 </tr>
1154 <tr>
1155 <td>640 dpi (xxxhdpi)</td>
1156 <td>256MB</td>
1157 </tr>
1158 <tr>
1159 <td rowspan="10">large</td>
1160 <td>120 dpi (ldpi)</td>
1161 <td>32MB</td>
1162 </tr>
1163 <tr>
1164 <td>160 dpi (mdpi)</td>
1165 <td>48MB</td>
1166 </tr>
1167 <tr>
1168 <td>213 dpi (tvdpi)</td>
1169 <td rowspan="2">80MB</td>
1170 </tr>
1171 <tr>
1172 <td>240 dpi (hdpi)</td>
1173 </tr>
1174 <tr>
1175 <td>280 dpi (280dpi)</td>
1176 <td>96MB</td>
1177 </tr>
1178 <tr>
1179 <td>320 dpi (xhdpi)</td>
1180 <td>128MB</td>
1181 </tr>
1182 <tr>
1183 <td>400 dpi (400dpi)</td>
1184 <td>192MB</td>
1185 </tr>
1186 <tr>
1187 <td>480 dpi (xxhdpi)</td>
1188 <td>256MB</td>
1189 </tr>
1190 <tr>
1191 <td>560 dpi (560dpi)</td>
1192 <td>384MB</td>
1193 </tr>
1194 <tr>
1195 <td>640 dpi (xxxhdpi)</td>
1196 <td>512MB</td>
1197 </tr>
1198 <tr>
1199 <td rowspan="10">xlarge</td>
1200 <td>120 dpi (ldpi)</td>
1201 <td>48MB</td>
1202 </tr>
1203 <tr>
1204 <td>160 dpi (mdpi)</td>
1205 <td>80MB</td>
1206 </tr>
1207 <tr>
1208 <td>213 dpi (tvdpi)</td>
1209 <td rowspan="2">96MB</td>
1210 </tr>
1211 <tr>
1212 <td>240 dpi (hdpi)</td>
1213 </tr>
1214 <tr>
1215 <td>280 dpi (280dpi)</td>
1216 <td>144MB</td>
1217 </tr>
1218 <tr>
1219 <td>320 dpi (xhdpi)</td>
1220 <td>192MB</td>
1221 </tr>
1222 <tr>
1223 <td>400 dpi (400dpi)</td>
1224 <td>288MB</td>
1225 </tr>
1226 <tr>
1227 <td>480 dpi (xxhdpi)</td>
1228 <td>384MB</td>
1229 </tr>
1230 <tr>
1231 <td>560 dpi (560dpi)</td>
1232 <td>576MB</td>
1233 </tr>
1234 <tr>
1235 <td>640 dpi (xxxhdpi)</td>
1236 <td>768MB</td>
1237 </tr>
1238</table>
1239
1240
1241<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1242
1243
1244<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1245
1246
1247<p>Android includes a launcher application (home screen) and support for
1248third-party applications to replace the device launcher (home screen). Device
1249implementations that allow third-party applications to replace the device home
1250screen MUST declare the platform feature android.software.home_screen.</p>
1251
1252<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1253
1254<div class="note">
1255<p>Widgets are optional for all Android device implementations, but SHOULD be
1256supported on Android Handheld devices.</p>
1257</div>
1258
1259
1260<p>Android defines a component type and corresponding API and lifecycle that
1261allows 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
1262implementations. Device implementations that support embedding widgets on the
1263home screen MUST meet the following requirements and declare support for
1264platform feature android.software.app_widgets.</p>
1265
1266<ul>
1267 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1268interface affordances to add, configure, view, and remove AppWidgets directly
1269within the Launcher.</li>
1270 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1271the standard grid size. See the App Widget Design Guidelines in the Android SDK
1272documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1273 <li>Device implementations that include support for lock screen MAY support
1274application widgets on the lock screen.</li>
1275</ul>
1276
1277<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1278
1279
1280<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>
1281
1282<p>Some APIs allow applications to perform notifications or attract attention
1283using hardware&#8212;specifically sound, vibration, and light. Device implementations
1284MUST support notifications that use hardware features, as described in the SDK
1285documentation, and to the extent possible with the device implementation
1286hardware. For instance, if a device implementation includes a vibrator, it MUST
1287correctly implement the vibration APIs. If a device implementation lacks
1288hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1289is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1290
1291<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1292etc.) provided for in the APIs
1293[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1294or in the Status/System Bar icon style guide
1295[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1296which in the case of an Android Television device includes the possibility to not display the
1297notifications. Device implementers MAY provide an alternative user experience for
1298notifications than that provided by the reference Android Open Source
1299implementation; however, such alternative notification systems MUST support
1300existing notification resources, as above. </p>
1301
1302<p>Android includes support for various notifications, such as:</p>
1303
1304<ul>
1305 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1306 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1307 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1308</ul>
1309
1310<p>Android device implementations, when such notifications are made visible, MUST properly execute
1311Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1312APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1313</p>
1314
1315<p>Android includes Notification Listener Service APIs that allow apps (once
1316explicitly enabled by the user) to receive a copy of all notifications as they
1317are posted or updated. Device implementations MUST correctly and promptly send
1318notifications in their entirety to all such installed and user-enabled listener
1319services, including any and all metadata attached to the Notification object.</p>
1320
1321<h3 id="3_8_4_search">3.8.4. Search</h3>
1322
1323
1324<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
1325expose their application&rsquo;s data into the global system search. Generally
1326speaking, this functionality consists of a single, system-wide user interface
1327that allows users to enter queries, displays suggestions as users type, and
1328displays results. The Android APIs allow developers to reuse this interface to
1329provide search within their own apps, and allow developers to supply results to
1330the common global search user interface.</p>
1331
1332<p>Android device implementations SHOULD include global search, a single, shared,
1333system-wide search user interface capable of real-time suggestions in response
1334to user input. Device implementations SHOULD implement the APIs that allow
1335developers to reuse this user interface to provide search within their own
1336applications. Device implementations that implement the global search interface
1337MUST implement the APIs that allow third-party applications to add suggestions
1338to the search box when it is run in global search mode. If no third-party
1339applications are installed that make use of this functionality, the default
1340behavior SHOULD be to display web search engine results and suggestions.</p>
1341
1342<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1343
1344
1345<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1346end 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
1347some high-visibility manner.</p>
1348
1349<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1350
1351
1352<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1353across an entire Activity or application.</p>
1354
1355<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1356application developers to use if they want to match the Holo theme look and
1357feel 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
1358exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1359
1360<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1361application developers to use if they want to match the design theme&rsquo;s look and
1362feel across the wide variety of different Android device types. Device
1363implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1364of 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>
1365
1366<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1367styles for application developers to use if they want to match the look and
1368feel of the device theme as defined by the device implementer. Device
1369implementations MAY modify the Device Default theme attributes exposed to
1370applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1371
1372<p>Android supports a new variant theme with translucent system bars, which allows
1373application developers to fill the area behind the status and navigation bar
1374with their app content. To enable a consistent developer experience in this
1375configuration, it is important the status bar icon style is maintained across
1376different device implementations. Therefore, Android device implementations
1377MUST use white for system status icons (such as signal strength and battery
1378level) and notifications issued by the system, unless the icon is indicating a
1379problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1380
1381<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1382
1383
1384<p>Android defines a component type and corresponding API and lifecycle that
1385allows 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
1386input capabilities that display as a wallpaper, behind other applications.</p>
1387
1388<p>Hardware is considered capable of reliably running live wallpapers if it can
1389run all live wallpapers, with no limitations on functionality, at a reasonable
1390frame rate with no adverse effects on other applications. If limitations in the
1391hardware cause wallpapers and/or applications to crash, malfunction, consume
1392excessive CPU or battery power, or run at unacceptably low frame rates, the
1393hardware is considered incapable of running live wallpaper. As an example, some
1394live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1395Live wallpaper will not run reliably on hardware that does not support multiple
1396OpenGL contexts because the live wallpaper use of an OpenGL context may
1397conflict with other applications that also use an OpenGL context.</p>
1398
1399<p>Device implementations capable of running live wallpapers reliably as described
1400above SHOULD implement live wallpapers, and when implemented MUST report the
1401platform feature flag android.software.live_wallpaper.</p>
1402
1403<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1404
1405<div class="note">
1406<p>As the Recent function navigation key is OPTIONAL, the requirements to
1407implement the overview screen is OPTIONAL for Android Television devices and
1408Android Watch devices.</p>
1409</div>
1410
1411
1412<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
1413accessed activities and tasks using a thumbnail image of the application&rsquo;s
1414graphical state at the moment the user last left the application. Device
1415implementations 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>
1416
1417<ul>
1418 <li>MUST display affiliated recents as a group that moves together.</li>
1419 <li>MUST support at least up to 20 displayed activities.</li>
1420 <li>MUST at least display the title of 4 activities at a time.</li>
1421 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1422 <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>
1423 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1424interacts with screens.</li>
1425</ul>
1426
1427<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1428interface (or a similar thumbnail-based interface) for the overview screen.</p>
1429
1430<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1431
1432
1433<p>Android includes support for Input Management and support for third-party input
1434method 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
1435the device MUST declare the platform feature android.software.input_methods and
1436support IME APIs as defined in the Android SDK documentation.</p>
1437
1438<p>Device implementations that declare the android.software.input_methods feature
1439MUST provide a user-accessible mechanism to add and configure third-party input
1440methods. Device implementations MUST display the settings interface in response
1441to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1442
1443<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1444
1445
1446<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1447Media Notification Template that allows media applications to integrate with
1448playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1449Device implementations that support a lock screen, unless an Android Automotive or Watch
1450implementation, MUST display the Lockscreen Notifications including the Media Notification
1451Template.</p>
1452
1453<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1454
1455
1456<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
1457a power source is idle or docked in a desk dock. Android Watch devices MAY
1458implement Dreams, but other types of device implementations SHOULD include
1459support for Dreams and provide a settings option for users to configure Dreams
1460in response to the android.settings.DREAM_SETTINGS intent.</p>
1461
1462<h3 id="3_8_12_location">3.8.12. Location</h3>
1463
1464
1465<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1466location coordinates, location modes MUST be displayed in the Location menu
1467within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1468
1469<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1470
1471
1472<p>Android includes support for color emoji characters. When Android device
1473implementations include an IME, devices SHOULD provide an input method to the
1474user 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>
1475
1476<p>Android includes support for Roboto 2 font with different
1477weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1478sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1479the languages available on the device and full Unicode 7.0 coverage of Latin,
1480Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1481all glyphs in the currency symbols block of Unicode 7.0.</p>
1482
1483<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1484
1485
1486<p>Android includes features that allow security-aware applications to perform
1487device administration functions at the system level, such as enforcing password
1488policies or performing remote wipe, through the Android Device Administration
1489API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1490Device implementations MUST provide an implementation of the DevicePolicyManager class
1491[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1492Device implementations that include support for PIN (numeric) or PASSWORD
1493(alphanumeric) based lock screens MUST support the full range of device
1494administration policies defined in the Android SDK documentation
1495[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1496and report the platform feature android.software.device_admin.</p>
1497
1498<p>Device implementations MAY have a preinstalled application performing device
1499administration functions but this application MUST NOT be set out-of-the box as
1500the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1501
1502<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1503
1504
1505<p>Android provides an accessibility layer that helps users with disabilities to
1506navigate their devices more easily. In addition, Android provides platform APIs
1507that enable accessibility service implementations to receive callbacks for user
1508and system events and generate alternate feedback mechanisms, such as
1509text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1510
1511<p>Device implementations include the following requirements:</p>
1512
1513<ul>
1514<li>Android Automotive implementations SHOULD provide an implementation of the
1515Android accessibility framework consistent with the default Android
1516implementation.</li>
1517<li>Device implementations (Android Automotive excluded) MUST provide an
1518implementation of the Android accessibility framework consistent with the
1519default Android implementation.</li>
1520<li>Device implementations (Android Automotive excluded) MUST support
1521third-party accessibility service implementations through the
1522android.accessibilityservice APIs
1523[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1524<li>Device implementations (Android Automotive excluded) MUST generate
1525AccessibilityEvents and deliver these events to all registered
1526AccessibilityService implementations in a manner consistent with the default
1527Android implementation</li>
1528<li> Device implementations (Android Automotive and Android Watch devices with
1529no audio output excluded), MUST provide a user-accessible mechanism to enable
1530and disable accessibility services, and MUST display this interface in response
1531to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1532</ul>
1533
1534<p>Additionally, device implementations SHOULD provide an implementation of an
1535accessibility service on the device, and SHOULD provide a mechanism for users
1536to enable the accessibility service during device setup. An open source
1537implementation of an accessibility service is available from the Eyes Free
1538project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1539
1540<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1541
1542
1543<p>Android includes APIs that allow applications to make use of text-to-speech
1544(TTS) services and allows service providers to provide implementations of TTS
1545services [<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
1546MUST meet these requirements related to the Android TTS framework. </p>
1547
1548<p>Android Automotive implementations:</p>
1549<ul>
1550<li>MUST support the Android TTS framework APIs.</li>
1551<li>MAY support installation of third-party TTS engines. If supported, partners
1552MUST provide a user-accessible interface that allows the user to select a TTS
1553engine for use at system level.</li>
1554</ul>
1555
1556<p>All other device implementations:</p>
1557
1558<ul>
1559 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1560supporting the languages available on the device. Note that the upstream
1561Android open source software includes a full-featured TTS engine
1562implementation.
1563 <li> MUST support installation of third-party TTS engines
1564 <li> MUST provide a user-accessible interface that allows users to select a TTS
1565engine for use at the system level
1566</ul>
1567
1568<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1569
1570
1571<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1572content to Android Television devices. TIF provides a standard API to create
1573input modules that control Android Television devices. Android Television
1574device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1575
1576<p>Device implementations that support TIF MUST declare the platform feature
1577android.software.live_tv.</p>
1578
1579<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1580
1581
1582<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1583by 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>
1584
1585<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
1586files from installing and running correctly on other compatible devices.</p>
1587
1588<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1589
1590
1591<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1592
1593
1594<p>Device implementations MUST support the core media formats specified in the
1595Android 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
1596implementations MUST support the media formats, encoders, decoders, file types,
1597and container formats defined in the tables below and reported via MediaCodecList
1598[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1599Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1600[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1601113</a>].
1602
1603All of these codecs are
1604provided as software implementations in the preferred Android implementation
1605from the Android Open Source Project.</p>
1606
1607<p>Please note that neither Google nor the Open Handset Alliance make any
1608representation that these codecs are free from third-party patents. Those
1609intending to use this source code in hardware or software products are advised
1610that implementations of this code, including in open source software or
1611shareware, may require patent licenses from the relevant patent holders.</p>
1612
1613<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1614
1615<table>
1616 <tr>
1617 <th>Format/Codec</th>
1618 <th>Encoder</th>
1619 <th>Decoder</th>
1620 <th>Details</th>
1621 <th>Supported File Types/Container Formats</th>
1622 </tr>
1623 <tr>
1624 <td>MPEG-4 AAC Profile</p>
1625
1626<p>(AAC LC)</td>
1627 <td>REQUIRED<sup>1</sup></td>
1628 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1629 <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]163048 kHz.</td>
1631 <td>
1632 <ul>
1633 <li class="table_list">3GPP (.3gp)</li>
1634 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1635 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1636supported)</li>
1637 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1638 </tr>
1639 <tr>
1640 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1641 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1642 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1643 <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]1644to 48 kHz.</td>
1645 <td></td>
1646 </tr>
1647 <tr>
1648 <td>MPEG-4 HE AACv2</p>
1649
1650<p>Profile (enhanced AAC+)</td>
1651 <td> </td>
1652 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1653 <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]1654to 48 kHz.</td>
1655 <td></td>
1656 </tr>
1657 <tr>
1658 <td>AAC ELD (enhanced low delay AAC)</td>
1659 <td>REQUIRED<sup>1</sup> </p>
1660
1661<p>(Android 4.1+)</td>
1662 <td>REQUIRED</p>
1663
1664<p>(Android 4.1+)</td>
1665 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1666 <td></td>
1667 </tr>
1668 <tr>
1669 <td>AMR-NB</td>
1670 <td>REQUIRED<sup>3</sup></td>
1671 <td>REQUIRED<sup>3</sup></td>
1672 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1673 <td>3GPP (.3gp)</td>
1674 </tr>
1675 <tr>
1676 <td>AMR-WB</td>
1677 <td>REQUIRED<sup>3</sup></td>
1678 <td>REQUIRED<sup>3</sup></td>
1679 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1680 <td></td>
1681 </tr>
1682 <tr>
1683 <td>FLAC</td>
1684 <td></td>
1685 <td>REQUIRED <br>(Android 3.1+)</td>
1686 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1687recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1688does not include a low-pass filter). 16-bit recommended; no dither applied for
168924-bit.</td>
1690 <td>FLAC (.flac) only</td>
1691 </tr>
1692 <tr>
1693 <td>MP3</td>
1694 <td></td>
1695 <td>REQUIRED</td>
1696 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1697 <td>MP3 (.mp3)</td>
1698 </tr>
1699 <tr>
1700 <td>MIDI</td>
1701 <td></td>
1702 <td>REQUIRED</td>
1703 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1704ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1705 <td><ul>
1706 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1707 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1708 <li class="table_list">OTA (.ota)</li>
1709 <li class="table_list">iMelody (.imy)</li></ul></td>
1710 </tr>
1711 <tr>
1712 <td>Vorbis</td>
1713 <td></td>
1714 <td>REQUIRED</td>
1715 <td></td>
1716 <td><ul>
1717 <li class="table_list">Ogg (.ogg)</li>
1718 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1719 </tr>
1720 <tr>
1721 <td>PCM/WAVE</td>
1722 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1723 <td>REQUIRED</td>
1724 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1725sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1726frequencies.</td>
1727 <td>WAVE (.wav)</td>
1728 </tr>
1729 <tr>
1730 <td>Opus</td>
1731 <td></td>
1732 <td>REQUIRED<br> (Android 5.0+)</td>
1733 <td></td>
1734 <td>Matroska (.mkv)</td>
1735 </tr>
1736</table>
1737
1738
1739<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1740but optional for Android Watch device implementations.</p>
1741
1742<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17432 channels is optional.</p>
1744
1745<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1746
1747<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1748including Android Watch device implementations.</p>
1749
1750<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1751
1752<table>
1753 <tr>
1754 <th>Format/Codec</th>
1755 <th>Encoder</th>
1756 <th>Decoder</th>
1757 <th>Details</th>
1758 <th>Supported File Types/Container Formats</th>
1759 </tr>
1760 <tr>
1761 <td>JPEG</td>
1762 <td>REQUIRED</td>
1763 <td>REQUIRED</td>
1764 <td>Base+progressive</td>
1765 <td>JPEG (.jpg)</td>
1766 </tr>
1767 <tr>
1768 <td>GIF</td>
1769 <td></td>
1770 <td>REQUIRED</td>
1771 <td></td>
1772 <td>GIF (.gif)</td>
1773 </tr>
1774 <tr>
1775 <td>PNG</td>
1776 <td>REQUIRED</td>
1777 <td>REQUIRED</td>
1778 <td></td>
1779 <td>PNG (.png)</td>
1780 </tr>
1781 <tr>
1782 <td>BMP</td>
1783 <td></td>
1784 <td>REQUIRED</td>
1785 <td></td>
1786 <td>BMP (.bmp)</td>
1787 </tr>
1788 <tr>
1789 <td>WebP</td>
1790 <td>REQUIRED</td>
1791 <td>REQUIRED</td>
1792 <td></td>
1793 <td>WebP (.webp)</td>
1794 </tr>
1795</table>
1796
1797
1798<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1799
1800<p>Video codecs are optional for Android Watch device implementations.</p>
1801
1802<table>
1803 <tr>
1804 <th>Format/Codec</th>
1805 <th>Encoder</th>
1806 <th>Decoder</th>
1807 <th>Details</th>
1808 <th>Supported File Types/<br>Container Formats</th>
1809 </tr>
1810 <tr>
1811 <td>H.263</td>
1812 <td>REQUIRED<sup>1</sup></td>
1813 <td>REQUIRED<sup>2</sup></td>
1814 <td></td>
1815 <td><ul>
1816 <li class="table_list">3GPP (.3gp)</li>
1817 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1818 </tr>
1819 <tr>
1820 <td>H.264 AVC</td>
1821 <td>REQUIRED<sup>2</sup></td>
1822 <td>REQUIRED<sup>2</sup></td>
1823 <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>
1824 <td><ul>
1825 <li class="table_list">3GPP (.3gp)</li>
1826 <li class="table_list">MPEG-4 (.mp4)</li>
1827 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1828 </tr>
1829 <tr>
1830 <td>H.265 HEVC</td>
1831 <td></td>
1832 <td>REQUIRED<sup>5</sup></td>
1833 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1834 <td>MPEG-4 (.mp4)</td>
1835 </tr>
1836 <tr>
1837 <td>MPEG-4 SP</td>
1838 <td></td>
1839 <td>REQUIRED<sup>2</sup></td>
1840 <td></td>
1841 <td>3GPP (.3gp)</td>
1842 </tr>
1843 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1844 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1845 <td>REQUIRED<sup>2</sup></p>
1846
1847<p>(Android 4.3+)</td>
1848 <td>REQUIRED<sup>2</sup></p>
1849
1850<p>(Android 2.3.3+)</td>
1851 <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>
1852 <td><ul>
1853 <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]1854 <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]1855 </tr>
1856 <tr>
1857 <td>VP9</td>
1858 <td></td>
1859 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1860 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1861 <td><ul>
1862 <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]1863 <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]1864 </tr>
1865</table>
1866
1867
1868<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1869android.hardware.camera or android.hardware.camera.front.</p>
1870
1871<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1872
1873<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1874device implementations SHOULD use a hardware VP8 codec that meets the
1875requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1876
1877<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1878
1879<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1880
1881<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1882
1883<div class="note">
1884<p>Video codecs are optional for Android Watch device implementations.</p>
1885</div>
1886
1887
1888<p>Android device implementations with H.264 codec support, MUST support Baseline
1889Profile Level 3 and the following SD (Standard Definition) video encoding
1890profiles and SHOULD support Main Profile Level 4 and the following HD (High
1891Definition) video encoding profiles. Android Television devices are STRONGLY
1892RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1893<table>
1894 <tr>
1895 <th></th>
1896 <th>SD (Low quality)</th>
1897 <th>SD (High quality)</th>
1898 <th>HD 720p1</th>
1899 <th>HD 1080p1</th>
1900 </tr>
1901 <tr>
1902 <th>Video resolution</th>
1903 <td>320 x 240 px</td>
1904 <td>720 x 480 px</td>
1905 <td>1280 x 720 px</td>
1906 <td>1920 x 1080 px</td>
1907 </tr>
1908 <tr>
1909 <th>Video frame rate</th>
1910 <td>20 fps</td>
1911 <td>30 fps</td>
1912 <td>30 fps</td>
1913 <td>30 fps</td>
1914 </tr>
1915 <tr>
1916 <th>Video bitrate</th>
1917 <td>384 Kbps</td>
1918 <td>2 Mbps</td>
1919 <td>4 Mbps</td>
1920 <td>10 Mbps</td>
1921 </tr>
1922</table>
1923
1924
1925<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1926devices.</p>
1927
1928<p>Android device implementations with VP8 codec support MUST support the SD video
1929encoding profiles and SHOULD support the following HD (High Definition) video
1930encoding profiles.</p>
1931<table>
1932 <tr>
1933 <th></th>
1934 <th>SD (Low quality)</th>
1935 <th>SD (High quality)</th>
1936 <th>HD 720p1</th>
1937 <th>HD 1080p1</th>
1938 </tr>
1939 <tr>
1940 <th>Video resolution</th>
1941 <td>320 x 180 px</td>
1942 <td>640 x 360 px</td>
1943 <td>1280 x 720 px</td>
1944 <td>1920 x 1080 px</td>
1945 </tr>
1946 <tr>
1947 <th>Video frame rate</th>
1948 <td>30 fps</td>
1949 <td>30 fps</td>
1950 <td>30 fps</td>
1951 <td>30 fps</td>
1952 </tr>
1953 <tr>
1954 <th>Video bitrate</th>
1955 <td>800 Kbps </td>
1956 <td>2 Mbps</td>
1957 <td>4 Mbps</td>
1958 <td>10 Mbps</td>
1959 </tr>
1960</table>
1961
1962<p class="table_footnote">1 When supported by hardware.</p>
1963
1964<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1965
1966<div class="note">
1967<p>Video codecs are optional for Android Watch device implementations.</p>
1968</div>
1969
1970
1971<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1972the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1973standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1974
1975<p>Android device implementations with H.264 decoders, MUST support Baseline
1976Profile Level 3 and the following SD video decoding profiles and SHOULD support
1977the HD decoding profiles. Android Television devices MUST support High Profile
1978Level 4.2 and the HD 1080p decoding profile.</p>
1979<table>
1980 <tr>
1981 <th></th>
1982 <th>SD (Low quality)</th>
1983 <th>SD (High quality)</th>
1984 <th>HD 720p1</th>
1985 <th>HD 1080p1</th>
1986 </tr>
1987 <tr>
1988 <th>Video resolution</th>
1989 <td>320 x 240 px</td>
1990 <td>720 x 480 px</td>
1991 <td>1280 x 720 px</td>
1992 <td>1920 x 1080 px</td>
1993 </tr>
1994 <tr>
1995 <th>Video frame rate</th>
1996 <td>30 fps</td>
1997 <td>30 fps</td>
1998 <td>30 fps / 60 fps2</td>
1999 <td>30 fps / 60 fps2</td>
2000 </tr>
2001 <tr>
2002 <th>Video bitrate</th>
2003 <td>800 Kbps </td>
2004 <td>2 Mbps</td>
2005 <td>8 Mbps</td>
2006 <td>20 Mbps</td>
2007 </tr>
2008</table>
2009
2010
2011<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2012types only when supported by hardware.</p>
2013
2014<p class="table_footnote">2 Required for Android Television device implementations.</p>
2015
2016<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
2017decoding profiles. Android Television devices MUST support the HD 1080p
2018decoding profile. </p>
2019<table>
2020 <tr>
2021 <th></th>
2022 <th>SD (Low quality)</th>
2023 <th>SD (High quality)</th>
2024 <th>HD 720p1</th>
2025 <th>HD 1080p1</th>
2026 </tr>
2027 <tr>
2028 <th>Video resolution</th>
2029 <td>320 x 180 px</td>
2030 <td>640 x 360 px</td>
2031 <td>1280 x 720 px</td>
2032 <td>1920 x 1080 px</td>
2033 </tr>
2034 <tr>
2035 <th>Video frame rate</th>
2036 <td>30 fps</td>
2037 <td>30 fps</td>
2038 <td>30 fps / 60 fps2</td>
2039 <td>30 / 60 fps2</td>
2040 </tr>
2041 <tr>
2042 <th>Video bitrate</th>
2043 <td>800 Kbps </td>
2044 <td>2 Mbps</td>
2045 <td>8 Mbps</td>
2046 <td>20 Mbps</td>
2047 </tr>
2048</table>
2049
2050
2051<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2052devices only when supported by hardware.</p>
2053
2054<p class="table_footnote">2 Required for Android Television device implementations.</p>
2055
2056<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
2057HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2058support the HD 1080p decoding profile and SHOULD support the UHD decoding
2059profile. When the UHD video decoding profile is supported, it MUST support 8
2060bit color depth.</p>
2061<table>
2062 <tr>
2063 <th></th>
2064 <th>SD (Low quality)</th>
2065 <th>SD (High quality)</th>
2066 <th>HD 720p 1</th>
2067 <th>HD 1080p 2</th>
2068 <th>UHD 2</th>
2069 </tr>
2070 <tr>
2071 <th>Video resolution</th>
2072 <td>320 x 180 px</td>
2073 <td>640 x 360 px</td>
2074 <td>1280 x 720 px</td>
2075 <td>1920 x 1080 px</td>
2076 <td>3840 x 2160 px</td>
2077 </tr>
2078 <tr>
2079 <th>Video frame rate</th>
2080 <td>30 fps</td>
2081 <td>30 fps</td>
2082 <td>30 fps</td>
2083 <td>30 fps</td>
2084 <td>30 fps</td>
2085 </tr>
2086 <tr>
2087 <th>Video bitrate</th>
2088 <td>600 Kbps </td>
2089 <td>1.6 Mbps</td>
2090 <td>4 Mbps</td>
2091 <td>10 Mbps</td>
2092 <td>20 Mbps</td>
2093 </tr>
2094</table>
2095
2096
2097<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2098devices only when supported by hardware.</p>
2099
2100<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2101supported by hardware.</p>
2102
2103<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
2104decoding profiles and SHOULD support the HD decoding profiles. Android
2105Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21061080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2107the UHD decoding profile.</p>
2108<table>
2109 <tr>
2110 <th></th>
2111 <th>SD (Low quality)</th>
2112 <th>SD (High quality)</th>
2113 <th>HD 720p </strong>1 </td>
2114 <th>HD 1080p </strong>1 </td>
2115 <th>UHD </strong>2</td>
2116 </tr>
2117 <tr>
2118 <th>Video resolution</th>
2119 <td>352 x 288 px</td>
2120 <td>640 x 360 px</td>
2121 <td>1280 x 720 px</td>
2122 <td>1920 x 1080 px</td>
2123 <td>3840 x 2160 px</td>
2124 </tr>
2125 <tr>
2126 <th>Video frame rate</th>
2127 <td>30 fps</td>
2128 <td>30 fps</td>
2129 <td>30 fps</td>
2130 <td>30 fps</td>
2131 <td>30 fps</td>
2132 </tr>
2133 <tr>
2134 <th>Video bitrate</th>
2135 <td>600 Kbps </td>
2136 <td>1.6 Mbps</td>
2137 <td>4 Mbps</td>
2138 <td>10 Mbps</td>
2139 <td>20 Mbps</td>
2140 </tr>
2141</table>
2142
2143
2144<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2145devices only when supported by hardware.</p>
2146
2147<p class="table_footnote">2 Required for Android Television device implementations when supported by
2148hardware.</p>
2149
2150<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2151
2152
2153<p>While some of the requirements outlined in this section are stated as SHOULD
2154since Android 4.3, the Compatibility Definition for a future version is planned
2155to change these to MUST. Existing and new Android devices are <strong>very strongly encouraged</strong> to meet these requirements, or they will not be able to attain Android
2156compatibility when upgraded to the future version.</p>
2157
2158<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2159
2160
2161<p>Device implementations that declare android.hardware.microphone MUST allow
2162capture of raw audio content with the following characteristics:</p>
2163
2164<ul>
2165 <li><strong>Format</strong>: Linear PCM, 16-bit
2166 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2167 <li><strong>Channels</strong>: Mono
2168</ul>
2169
2170<p>Device implementations that declare android.hardware.microphone SHOULD allow
2171capture of raw audio content with the following characteristics:</p>
2172
2173<ul>
2174 <li><strong>Format</strong>: Linear PCM, 16-bit
2175 <li><strong>Sampling rates</strong>: 22050, 48000
2176 <li><strong>Channels</strong>: Stereo
2177</ul>
2178
2179<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2180
2181
2182<p>In addition to the above recording specifications, when an application has
2183started recording an audio stream using the
2184android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2185
2186<ul>
2187 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2188characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2189 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2190source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2191 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2192dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2193 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2194level at the microphone.
2195 <li>Noise reduction processing, if present, MUST be disabled.
2196 <li>Automatic gain control, if present, MUST be disabled
2197</ul>
2198
2199<p>If the platform supports noise suppression technologies tuned for speech
2200recognition, the effect MUST be controllable from the
2201android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2202noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2203of the noise suppression technology.</p>
2204
2205<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2206
2207
2208<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2209audio source. Devices that declare android.hardware.audio.output MUST properly
2210implement the REMOTE_SUBMIX audio source so that when an application uses the
2211android.media.AudioRecord API to record from this audio source, it can capture
2212a mix of all audio streams except for the following:</p>
2213
2214<ul>
2215 <li>STREAM_RING
2216 <li>STREAM_ALARM
2217 <li>STREAM_NOTIFICATION
2218</ul>
2219
2220<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2221
2222
2223<p>Device implementations that declare android.hardware.audio.output MUST conform
2224to the requirements in this section.</p>
2225
2226<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2227
2228
2229<p>The device MUST allow playback of raw audio content with the following
2230characteristics:</p>
2231
2232<ul>
2233 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2234 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2235 <li><strong>Channels</strong>: Mono, Stereo</li>
2236</ul>
2237
2238<p>The device SHOULD allow playback of raw audio content with the following
2239characteristics:</p>
2240
2241<ul>
2242 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2243</ul>
2244
2245<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2246
2247
2248<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
2249android.hardware.audio.output:</p>
2250
2251<ul>
2252 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2253implementations controllable through the AudioEffect subclasses Equalizer,
2254LoudnessEnhancer.</li>
2255 <li>MUST support the visualizer API implementation, controllable through the
2256Visualizer class.</li>
2257 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2258EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2259controllable through the AudioEffect sub-classes BassBoost,
2260EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2261</ul>
2262
2263<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2264
2265
2266<p>Android Television device implementations MUST include support for system
2267Master Volume and digital audio output volume attenuation on supported outputs,
2268except for compressed audio passthrough output (where no audio decoding is done
2269on the device).</p>
2270
2271<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2272
2273
2274<p>Audio latency is the time delay as an audio signal passes through a system.
2275Many classes of applications rely on short latencies, to achieve real-time
2276sound effects.</p>
2277
2278<p>For the purposes of this section, use the following definitions:</p>
2279
2280<ul>
2281 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2282when the corresponding sound can be heard by an external listener or observed
2283by a transducer.</li>
2284 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2285idle and powered down prior to the request.</li>
2286 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2287 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2288when an application reads the corresponding frame of PCM-coded data.</li>
2289 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2290audio input system has been idle and powered down prior to the request.</li>
2291 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2292 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2293 <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^]2294 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2295 one buffer period.
2296 The buffer period term allows processing time for the app and for the app to
2297 mitigate phase difference between input and output streams.
2298 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2299 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2300NDK_root/docs/opensles/index.html.</li>
2301</ul>
2302
2303<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2304or exceed these audio output requirements:</p>
2305
2306<ul>
2307 <li>cold output latency of 100 milliseconds or less</li>
2308 <li>continuous output latency of 45 milliseconds or less</li>
2309 <li>minimize the cold output jitter</li>
2310</ul>
2311
2312<p>If a device implementation meets the requirements of this section after any
2313initial calibration when using the OpenSL ES PCM buffer queue API, for
2314continuous output latency and cold output latency over at least one supported
2315audio output device, it MAY report support for low-latency audio, by reporting
2316the feature android.hardware.audio.low_latency via the
2317android.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
2318MUST NOT report support for low-latency audio.</p>
2319
2320<p>Device implementations that include android.hardware.microphone SHOULD meet
2321these input audio requirements:</p>
2322
2323<ul>
2324 <li>cold input latency of 100 milliseconds or less</li>
2325 <li>continuous input latency of 30 milliseconds or less</li>
2326 <li>continuous round-trip latency of 50 milliseconds or less</li>
2327 <li>minimize the cold input jitter</li>
2328</ul>
2329
2330<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2331
2332
2333<p>Devices MUST support the media network protocols for audio and video playback
2334as 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>
2335
2336<ul>
2337 <li>RTSP (RTP, SDP)</li>
2338 <li>HTTP(S) progressive streaming</li>
2339 <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>
2340</ul>
2341
2342<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2343
2344
2345<p>Device implementations that support secure video output and are capable of
2346supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2347implementations that declare support for Display.FLAG_SECURE, if they support a
2348wireless display protocol, MUST secure the link with a cryptographically strong
2349mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2350if they support a wired external display, the device implementations MUST
2351support HDCP 1.2 or higher. Android Television device implementations MUST
2352support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2353lower resolutions. The upstream Android open source implementation includes
2354support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2355requirement.</p>
2356
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2357<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2358
2359<p>
2360If a device implementation supports the inter-app MIDI software transport
2361(virtual MIDI devices), and it supports MIDI over
2362<em>all</em> of the following MIDI-capable hardware transports
2363for which it provides generic non-MIDI connectivity, it MAY report
2364support for feature android.software.midi via the
2365android.content.pm.PackageManager class
2366[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2367</p>
2368
2369<p>The MIDI-capable hardware transports are:</p>
2370<ul>
2371 <li>USB host mode (section 7.7 USB)</li>
2372 <li>USB peripheral mode (section 7.7 USB)</li>
2373</ul>
2374
2375<p>
2376Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2377MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2378it MUST NOT report support for feature android.software.midi.
2379</p>
2380
2381<p>
2382MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2383is in trial use status. A device implementation that reports
2384feature android.software.midi, and which provides generic non-MIDI connectivity
2385over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2386</p>
2387
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame^]2388<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2389
2390<p>
2391If a device implementation meets <em>all</em> of the following requirements,
2392it MAY report support for feature android.hardware.audio.pro via the
2393android.content.pm.PackageManager class
2394[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2395</p>
2396
2397<ul>
2398
2399<li>
2400The device implementation MUST support android.hardware.audio.low_latency
2401</li>
2402
2403<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2404MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2405supported path.
2406</li>
2407
2408<li>
2409If the device implementation includes a 4 conductor 3.5mm audio jack,
2410the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2411and SHOULD be 10 milliseconds or less over at the audio jack path.
2412</li>
2413
2414<li>
2415The device implementation MUST include a USB port(s) supporting USB host mode and
2416USB peripheral mode.
2417</li>
2418
2419<li>
2420The USB host mode MUST implement the USB audio class and handle concurrent input/output with
2421a USB audio class-compliant peripheral having the following minimum capabilities:
2422<ul>
2423<li>4-channel input</li>
2424<li>4-channel output</li>
2425<li>24-bit depth PCM</li>
2426<li>96 kHz sample rate</li>
2427</ul>
2428</li>
2429
2430<li>
2431If the device includes an HDMI port, the device implementation
2432MUST support output in stereo and 8 channels
2433at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2434</li>
2435
2436<li>
2437The device implementation MUST report support for feature android.software.midi.
2438</li>
2439
2440</ul>
2441
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2442<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2443
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2444<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2445
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2446<p>Device implementations MUST support the Android Developer Tools provided in the
2447Android SDK. Android compatible devices MUST be compatible with:</p>
2448
2449<ul>
2450 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2451</ul>
2452
2453<p>Device implementations MUST support all adb functions as documented in the
2454Android 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
2455user-accessible mechanism to turn on the Android Debug Bridge. If a device
2456implementation omits USB peripheral mode, it MUST implement the Android Debug
2457Bridge via local-area network (such as Ethernet or 802.11). </p>
2458
2459<p>Android includes support for secure adb. Secure adb enables adb on known
2460authenticated hosts. Device implementations MUST support secure adb.</p>
2461
2462<ul>
2463 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2464</ul>
2465
2466<p>Device implementations MUST support all ddms features as documented in the
2467Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2468but MUST be supported whenever the user has activated the Android Debug Bridge,
2469as above.</p>
2470
2471<ul>
2472 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2473</ul>
2474
2475<p>Device implementations MUST include the Monkey framework, and make it available
2476for applications to use.</p>
2477
2478<ul>
2479 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2480</ul>
2481
2482<p>Device implementations MUST support systrace tool as documented in the Android
2483SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2484mechanism to turn on Systrace.</p>
2485
2486<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2487using the standard Android SDK tools, without additional support; however
2488Microsoft Windows systems typically require a driver for new Android devices.
2489(For instance, new vendor IDs and sometimes new device IDs require custom USB
2490drivers for Windows systems.) If a device implementation is unrecognized by the
2491adb tool as provided in the standard Android SDK, device implementers MUST
2492provide Windows drivers allowing developers to connect to the device using the
2493adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2494Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2495
2496<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2497
2498
2499<p>Android includes support for developers to configure application
2500development-related settings. Device implementations MUST honor the
2501android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2502development-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
2503default and enables users to launch Developer Options after pressing seven (7)
2504times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2505Developer Options. Specifically, device implementations MUST hide Developer
2506Options by default and MUST provide a mechanism to enable Developer Options
2507that is consistent with the upstream Android implementation.</p>
2508
2509<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2510
2511
2512<p>If a device includes a particular hardware component that has a corresponding
2513API for third-party developers, the device implementation MUST implement that
2514API as described in the Android SDK documentation. If an API in the SDK
2515interacts with a hardware component that is stated to be optional and the
2516device implementation does not possess that component:</p>
2517
2518<ul>
2519 <li>Complete class definitions (as documented by the SDK) for the component APIs
2520MUST still be presented.
2521 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2522 <li>API methods MUST return null values where permitted by the SDK documentation.
2523 <li>API methods MUST return no-op implementations of classes where null values are
2524not permitted by the SDK documentation.
2525 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2526</ul>
2527
2528<p>A typical example of a scenario where these requirements apply is the telephony
2529API: even on non-phone devices, these APIs must be implemented as reasonable
2530no-ops.</p>
2531
2532<p>Device implementations MUST consistently report accurate hardware configuration
2533information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2534methods on the android.content.pm.PackageManager class for the same build
2535fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2536
2537<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2538
2539
2540<p>Android includes facilities that automatically adjust application assets and UI
2541layouts appropriately for the device, to ensure that third-party applications
2542run 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
2543this section.</p>
2544
2545<p>The units referenced by the requirements in this section are defined as
2546follows:</p>
2547
2548<ul>
2549 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2550of the display.</li>
2551 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
25521&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2553within the range.</li>
2554 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2555 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2556 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2557 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2558dps * (density/160).</li>
2559</ul>
2560
2561<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2562
2563
2564<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2565
2566<div class="note">
2567<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>
2568</div>
2569
2570<p>The Android UI framework supports a variety of different screen sizes, and
2571allows applications to query the device screen size (aka &ldquo;screen layout") via
2572android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2573Device implementations MUST report the correct screen size as defined in the
2574Android 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
2575implementations MUST report the correct screen size according to the following
2576logical density-independent pixel (dp) screen dimensions.</p>
2577
2578<ul>
2579 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2580is an Android Watch device.</li>
2581 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2582dp x 320 dp.</li>
2583 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2584dp x 480 dp.</li>
2585 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2586dp x 720 dp.</li>
2587</ul>
2588
2589<p>In addition, </p>
2590
2591<ul>
2592 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2593range from 1.1 to 2.5 inches.</li>
2594 <li>Other types of Android device implementations, with a physically integrated
2595screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2596</ul>
2597
2598<p>Devices MUST NOT change their reported screen size at any time.</p>
2599
2600<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2601&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2602implementations MUST correctly honor applications' stated support for small,
2603normal, large, and xlarge screens, as described in the Android SDK
2604documentation.</p>
2605
2606<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2607
2608<div class="note">
2609<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2610</div>
2611
2612
2613<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
261416:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2615such a device implementation will use a UI_MODE_TYPE_WATCH as the
2616android.content.res.Configuration.uiMode.</p>
2617
2618<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2619
2620
2621<p>The Android UI framework defines a set of standard logical densities to help
2622application developers target application resources. Device implementations
2623MUST report only one of the following logical Android framework densities
2624through the android.util.DisplayMetrics APIs, and MUST execute applications at
2625this standard density and MUST NOT change the value at at any time for the
2626default display.</p>
2627
2628<ul>
2629 <li>120 dpi (ldpi)</li>
2630 <li>160 dpi (mdpi)</li>
2631 <li>213 dpi (tvdpi)</li>
2632 <li>240 dpi (hdpi)</li>
2633 <li>280 dpi (280dpi)</li>
2634 <li>320 dpi (xhdpi)</li>
2635 <li>400 dpi (400dpi)</li>
2636 <li>480 dpi (xxhdpi)</li>
2637 <li>560 dpi (560dpi)</li>
2638 <li>640 dpi (xxxhdpi)</li>
2639</ul>
2640
2641<p>Device implementations SHOULD define the standard Android framework density
2642that is numerically closest to the physical density of the screen, unless that
2643logical density pushes the reported screen size below the minimum supported. If
2644the standard Android framework density that is numerically closest to the
2645physical density results in a screen size that is smaller than the smallest
2646supported compatible screen size (320 dp width), device implementations SHOULD
2647report the next lowest standard Android framework density.</p>
2648
2649<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2650
2651
2652<p>Device implementations MUST report correct values for all display metrics
2653defined 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
2654external screen is used as the default display.</p>
2655
2656<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2657
2658
2659<p>Devices MUST report which screen orientations they support
2660(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2661MUST report at least one supported orientation. For example, a device with a
2662fixed orientation landscape screen, such as a television or laptop, SHOULD only
2663report android.hardware.screen.landscape.</p>
2664
2665<p>Devices that report both screen orientations MUST support dynamic orientation
2666by applications to either portrait or landscape screen orientation. That is,
2667the device must respect the application&rsquo;s request for a specific screen
2668orientation. Device implementations MAY select either portrait or landscape
2669orientation as the default.</p>
2670
2671<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2672whenever queried via the android.content.res.Configuration.orientation,
2673android.view.Display.getOrientation(), or other APIs.</p>
2674
2675<p>Devices MUST NOT change the reported screen size or density when changing
2676orientation.</p>
2677
2678<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2679
2680
2681<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2682detailed in the Android SDK documentations. Device implementations SHOULD
2683support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2684implementations MUST also support Android RenderScript, as detailed in the
2685Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2686
2687<p>Device implementations MUST also correctly identify themselves as supporting
2688OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2689
2690<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2691 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2692for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2693 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2694libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2695ES 2.0.</li>
2696 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2697support the corresponding managed APIs and include support for native C/C++
2698APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2699libGLESv2.so MUST export the corresponding function symbols in addition to the
2700OpenGL ES 2.0 function symbols.</li>
2701</ul>
2702
2703<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2704interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2705and the ASTC texture compression format. Android device implementations MAY
2706support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2707support through the android.hardware.opengles.aep feature flag.</p>
2708
2709<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2710However, device implementations MUST report via the OpenGL ES managed and
2711native APIs all extension strings that they do support, and conversely MUST NOT
2712report extension strings that they do not support.</p>
2713
2714<p>Note that Android includes support for applications to optionally specify that
2715they require specific OpenGL texture compression formats. These formats are
2716typically vendor-specific. Device implementations are not required by Android
2717to implement any specific texture compression format. However, they SHOULD
2718accurately report any texture compression formats that they do support, via the
2719getString() method in the OpenGL API.</p>
2720
2721<p>Android includes a mechanism for applications to declare that they want to
2722enable hardware acceleration for 2D graphics at the Application, Activity,
2723Window, or View level through the use of a manifest tag
2724android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2725
2726<p>Device implementations MUST enable hardware acceleration by default, and MUST
2727disable hardware acceleration if the developer so requests by setting
2728android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2729through the Android View APIs.</p>
2730
2731<p>In addition, device implementations MUST exhibit behavior consistent with the
2732Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2733
2734<p>Android includes a TextureView object that lets developers directly integrate
2735hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2736Device implementations MUST support the TextureView API, and MUST exhibit
2737consistent behavior with the upstream Android implementation.</p>
2738
2739<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2740that indicates whether the EGLConfig supports rendering to an ANativeWindow
2741that records images to a video. Device implementations MUST support
2742EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2743
2744<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2745
2746
2747<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2748'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2749applications not developed for old versions of Android that pre-date
2750screen-size independence.</p>
2751
2752<ul>
2753<li>Android Automotive does not support legacy compatibility mode.</li>
2754<li>All other device implementations MUST include support for legacy application
2755compatibility mode as implemented by the upstream Android open source code. That
2756is, device implementations MUST NOT alter the triggers or thresholds at which
2757compatibility mode is activated, and MUST NOT alter the behavior of the
2758compatibility mode itself.</li>
2759</ul>
2760
2761<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2762
2763
2764<p>The Android platform includes APIs that allow applications to render rich
2765graphics to the display. Devices MUST support all of these APIs as defined by
2766the Android SDK unless specifically allowed in this document. </p>
2767
2768<ul>
2769 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2770SHOULD support displays capable of 24-bit color graphics.</li>
2771 <li>Devices MUST support displays capable of rendering animations.</li>
2772 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2773and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
277415% tolerance.</li>
2775</ul>
2776
2777<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2778
2779
2780<p>Android includes support for secondary display to enable media sharing
2781capabilities and developer APIs for accessing external displays. If a device
2782supports an external display either via a wired, wireless, or an embedded
2783additional display connection then the device implementation MUST implement the
2784display 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>
2785
2786<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2787
2788<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2789for non-touch navigation.</p>
2790
2791<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2792
2793<div class="note">
2794<p>Android Watch and Android Automotive implementations MAY implement a soft
2795keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2796</div>
2797
2798
2799<p>Device implementations:</p>
2800
2801<ul>
2802 <li>MUST include support for the Input Management Framework (which allows
2803third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2804detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2805 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2806hard keyboard is present) except for Android Watch devices where the screen
2807size makes it less reasonable to have a soft keyboard.</li>
2808 <li>MAY include additional soft keyboard implementations.</li>
2809 <li>MAY include a hardware keyboard.</li>
2810 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2811specified 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>
2812</ul>
2813
2814<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2815
2816<div class="note">
2817<p>Android Television devices MUST support D-pad.</p>
2818</div>
2819
2820<p>Device implementations:</p>
2821
2822<ul>
2823 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2824device implementation is not an Android Television device.</li>
2825 <li>MUST report the correct value for android.content.res.Configuration.navigation
2826[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2827 <li>MUST provide a reasonable alternative user interface mechanism for the
2828selection and editing of text, compatible with Input Management Engines. The
2829upstream Android open source implementation includes a selection mechanism
2830suitable for use with devices that lack non-touch navigation inputs.</li>
2831</ul>
2832
2833<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2834
2835<div class="note">
2836<p>The availability and visibility requirement of the Home, Recents, and Back
2837functions differ between device types as described in this section.</p>
2838</div>
2839
2840<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2841KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2842navigation paradigm and therefore:</p>
2843
2844<ul>
2845 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2846Back functions.</li>
2847 <li>Android Television device implementations MUST provide the Home and Back
2848functions.</li>
2849 <li>Android Watch device implementations MUST have the Home function available to
2850the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2851 <li>Android Automotive implementations MUST provide the Home function and MAY
2852provide Back and Recent functions.</li>
2853 <li>All other types of device implementations MUST provide the Home and Back
2854functions.</li>
2855</ul>
2856
2857<p>These functions MAY be implemented via dedicated physical buttons (such as
2858mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2859software keys on a distinct portion of the screen, gestures, touch panel, etc.
2860Android supports both implementations. All of these functions MUST be
2861accessible with a single action (e.g. tap, double-click or gesture) when
2862visible.</p>
2863
2864<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2865together with other navigation functions in full-screen mode. This does not
2866apply to devices upgrading from earlier Android versions that have physical
2867buttons for navigation and no recents key.</p>
2868
2869<p> The Home and Back functions, if provided, MUST each have a visible button or
2870icon unless hidden together with other navigation functions in full-screen mode
2871or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2872
2873<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2874Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2875implement a dedicated physical button for the Menu function. Older device
2876implementations SHOULD NOT implement a dedicated physical button for the Menu
2877function, but if the physical Menu button is implemented and the device is
2878running applications with targetSdkVersion > 10, the device implementation:</p>
2879
2880<ul>
2881 <li>MUST display the action overflow button on the action bar when it is visible
2882and the resulting action overflow menu popup is not empty. For a device
2883implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2884is RECOMMENDED.</li>
2885 <li>MUST NOT modify the position of the action overflow popup displayed by
2886selecting the overflow button in the action bar.</li>
2887 <li>MAY render the action overflow popup at a modified position on the screen when
2888it is displayed by selecting the physical menu button.</li>
2889</ul>
2890
2891<p>For backwards compatibility, device implementations MUST make the Menu function
2892available to applications when targetSdkVersion is less than 10, either by a physical
2893button, a software key, or gestures. This Menu function should be presented
2894unless hidden together with other navigation functions.</p>
2895
2896<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
2897the Assist action available to the user at all times when running applications.
2898The Assist action SHOULD be implemented as a long-press on the Home button or a
2899swipe-up gesture on the software Home key. This function MAY be implemented via
2900another physical button, software key, or gesture, but MUST be accessible with
2901a single action (e.g. tap, double-click, or gesture) when other navigation keys
2902are visible.</p>
2903
2904<p>Device implementations MAY use a distinct portion of the screen to display the
2905navigation keys, but if so, MUST meet these requirements:</p>
2906
2907<ul>
2908 <li>Device implementation navigation keys MUST use a distinct portion of the
2909screen, not available to applications, and MUST NOT obscure or otherwise
2910interfere with the portion of the screen available to applications.</li>
2911 <li>Device implementations MUST make available a portion of the display to
2912applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2913 <li>Device implementations MUST display the navigation keys when applications do
2914not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2915 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2916profile&rdquo; (eg. dimmed) mode when applications specify
2917SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2918 <li>Device implementations MUST hide the navigation keys when applications specify
2919SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2920</ul>
2921
2922<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2923
2924<div class="note">
2925<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2926</div>
2927
2928
2929<p>Device implementations SHOULD have a pointer input system of some kind (either
2930mouse-like or touch). However, if a device implementation does not support a
2931pointer input system, it MUST NOT report the android.hardware.touchscreen or
2932android.hardware.faketouch feature constant. Device implementations that do
2933include a pointer input system:</p>
2934
2935<ul>
2936 <li>SHOULD support fully independently tracked pointers, if the device input system
2937supports multiple pointers.</li>
2938 <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>
2939</ul>
2940
2941<p>Android includes support for a variety of touchscreens, touch pads, and fake
2942touch input devices. Touchscreen based device implementations are associated
2943with 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
2944screen. Since the user is directly touching the screen, the system does not
2945require any additional affordances to indicate the objects being manipulated.
2946In contrast, a fake touch interface provides a user input system that
2947approximates a subset of touchscreen capabilities. For example, a mouse or
2948remote control that drives an on-screen cursor approximates touch, but requires
2949the user to first point or focus then click. Numerous input devices like the
2950mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2951trackpad can support fake touch interactions. Android includes the feature
2952constant android.hardware.faketouch, which corresponds to a high-fidelity
2953non-touch (pointer-based) input device such as a mouse or trackpad that can
2954adequately emulate touch-based input (including basic gesture support), and
2955indicates that the device supports an emulated subset of touchscreen
2956functionality. Device implementations that declare the fake touch feature MUST
2957meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2958
2959<p>Device implementations MUST report the correct feature corresponding to the
2960type of input used. Device implementations that include a touchscreen
2961(single-touch or better) MUST report the platform feature constant
2962android.hardware.touchscreen. Device implementations that report the platform
2963feature constant android.hardware.touchscreen MUST also report the platform
2964feature constant android.hardware.faketouch. Device implementations that do not
2965include a touchscreen (and rely on a pointer device only) MUST NOT report any
2966touchscreen feature, and MUST report only android.hardware.faketouch if they
2967meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2968
2969<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2970
2971
2972<p>Device implementations that declare support for android.hardware.faketouch:</p>
2973
2974<ul>
2975 <li>MUST report the absolute X and Y screen positions of the pointer location and
2976display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2977 <li>MUST report touch event with the action code that specifies the state change
2978that 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>
2979 <li>MUST support pointer down and up on an object on the screen, which allows users
2980to emulate tap on an object on the screen.</li>
2981 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2982place on an object on the screen within a time threshold, which allows users to
2983emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2984 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2985any other arbitrary point on the screen, followed by a pointer up, which allows
2986users to emulate a touch drag.</li>
2987 <li>MUST support pointer down then allow users to quickly move the object to a
2988different position on the screen and then pointer up on the screen, which
2989allows users to fling an object on the screen.</li>
2990</ul>
2991
2992<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2993MUST meet the requirements for faketouch above, and MUST also support distinct
2994tracking of two or more independent pointer inputs.</p>
2995
2996<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
2997
2998
2999<p>Android Television device implementations MUST support button mappings for game
3000controllers as listed below. The upstream Android implementation includes
3001implementation for game controllers that satisfies this requirement. </p>
3002
3003<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3004
3005
3006<p>Android Television device implementations MUST support the following key
3007mappings:</p>
3008<table>
3009 <tr>
3010 <th>Button</th>
3011 <th>HID Usage</strong><sup>2</sup></td>
3012 <th>Android Button</th>
3013 </tr>
3014 <tr>
3015 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3016 <td>0x09 0x0001</td>
3017 <td>KEYCODE_BUTTON_A (96)</td>
3018 </tr>
3019 <tr>
3020 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3021 <td>0x09 0x0002</td>
3022 <td>KEYCODE_BUTTON_B (97)</td>
3023 </tr>
3024 <tr>
3025 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3026 <td>0x09 0x0004</td>
3027 <td>KEYCODE_BUTTON_X (99)</td>
3028 </tr>
3029 <tr>
3030 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3031 <td>0x09 0x0005</td>
3032 <td>KEYCODE_BUTTON_Y (100)</td>
3033 </tr>
3034 <tr>
3035 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
3036
3037<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]3038 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3039 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3040 </tr>
3041 <tr>
3042 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3043
3044<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]3045 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3046 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3047 </tr>
3048 <tr>
3049 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3050 <td>0x09 0x0007</td>
3051 <td>KEYCODE_BUTTON_L1 (102)</td>
3052 </tr>
3053 <tr>
3054 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3055 <td>0x09 0x0008</td>
3056 <td>KEYCODE_BUTTON_R1 (103)</td>
3057 </tr>
3058 <tr>
3059 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3060 <td>0x09 0x000E</td>
3061 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3062 </tr>
3063 <tr>
3064 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3065 <td>0x09 0x000F</td>
3066 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3067 </tr>
3068 <tr>
3069 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3070 <td>0x0c 0x0223</td>
3071 <td>KEYCODE_HOME (3)</td>
3072 </tr>
3073 <tr>
3074 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3075 <td>0x0c 0x0224</td>
3076 <td>KEYCODE_BACK (4)</td>
3077 </tr>
3078</table>
3079
3080
3081<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3082
3083<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3084
3085<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3086Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3087Report Size of 4. The logical value is defined to be the clockwise rotation
3088away from the vertical axis; for example, a logical value of 0 represents no
3089rotation and the up button being pressed, while a logical value of 1 represents
3090a rotation of 45 degrees and both the up and left keys being pressed.</p>
3091
3092<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3093
3094<table>
3095 <tr>
3096 <th>Analog Controls</strong><sup>1</sup></td>
3097 <th>HID Usage</th>
3098 <th>Android Button</th>
3099 </tr>
3100 <tr>
3101 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3102 <td>0x02 0x00C5</td>
3103 <td>AXIS_LTRIGGER </td>
3104 </tr>
3105 <tr>
3106 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3107 <td>0x02 0x00C4</td>
3108 <td>AXIS_RTRIGGER </td>
3109 </tr>
3110 <tr>
3111 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3112 <td>0x01 0x0030</p>
3113
3114<p>0x01 0x0031</td>
3115 <td>AXIS_X</p>
3116
3117<p>AXIS_Y</td>
3118 </tr>
3119 <tr>
3120 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3121 <td>0x01 0x0032</p>
3122
3123<p>0x01 0x0035</td>
3124 <td>AXIS_Z</p>
3125
3126<p>AXIS_RZ</td>
3127 </tr>
3128</table>
3129
3130
3131<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3132
3133<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3134
3135
3136<p>Android Television device implementations SHOULD provide a remote control to
3137allow users to access the TV interface. The remote control MAY be a physical
3138remote or can be a software-based remote that is accessible from a mobile phone
3139or tablet. The remote control MUST meet the requirements defined below.</p>
3140
3141<ul>
3142 <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>
3143 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3144support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3145</ul>
3146
3147<h2 id="7_3_sensors">7.3. Sensors</h2>
3148
3149
3150<p>Android includes APIs for accessing a variety of sensor types. Devices
3151implementations generally MAY omit these sensors, as provided for in the
3152following subsections. If a device includes a particular sensor type that has a
3153corresponding API for third-party developers, the device implementation MUST
3154implement that API as described in the Android SDK documentation and the
3155Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3156
3157<ul>
3158 <li>MUST accurately report the presence or absence of sensors per the
3159android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3160 <li>MUST return an accurate list of supported sensors via the
3161SensorManager.getSensorList() and similar methods.</li>
3162 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3163true or false as appropriate when applications attempt to register listeners,
3164not calling sensor listeners when the corresponding sensors are not present;
3165etc.).</li>
3166 <li>MUST report all sensor measurements using the relevant International System of
3167Units (metric) values for each sensor type as defined in the Android SDK
3168documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3169 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3170documentation, representing the time the event happened and synchronized with
3171the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3172are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3173platform releases where this might become a REQUIRED component. The
3174synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3175</ul>
3176
3177<p>The list above is not comprehensive; the documented behavior of the Android SDK
3178and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3179
3180<p>Some sensor types are composite, meaning they can be derived from data provided
3181by one or more other sensors. (Examples include the orientation sensor, and the
3182linear acceleration sensor.) Device implementations SHOULD implement these
3183sensor types, when they include the prerequisite physical sensors as described
3184in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3185If a device implementation includes a composite sensor it MUST implement the
3186sensor as described in the Android Open Source documentation on composite
3187sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3188
3189<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3190continuously [<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
3191sensor, device implementations MUST continuously provide periodic data samples
3192that SHOULD have a jitter below 3%, where jitter is defined as the standard
3193deviation of the difference of the reported timestamp values between
3194consecutive events.</p>
3195
3196<p>Note that the device implementations MUST ensure that the sensor event stream
3197MUST NOT prevent the device CPU from entering a suspend state or waking up from
3198a suspend state.</p>
3199
3200<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3201exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3202
3203<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3204
3205
3206<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3207devices and Android Watch devices are strongly encouraged to include this
3208sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3209
3210<ul>
3211 <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>
3212 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3213 Android Watch devices as such devices have a stricter power constraint and
3214 100 Hz for all other device types.</li>
3215 <li>SHOULD report events up to at least 200 Hz.</li>
3216 <li>MUST comply with the Android sensor coordinate system as detailed in the
3217Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3218 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3219more on any axis.</li>
3220 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3221least 16-bits.</li>
3222 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3223cycle and compensated, and preserve the compensation parameters between device
3224reboots.</li>
3225 <li>SHOULD be temperature compensated.</li>
3226 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3227deviation should be calculated on a per axis basis on samples collected over a
3228period of at least 3 seconds at the fastest sampling rate.</li>
3229 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3230TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3231Android SDK document. Existing and new Android devices are <strong>very strongly encouraged</strong> to implement the TYPE_SIGNIFICANT_MOTION composite sensor. If any of these
3232sensors are implemented, the sum of their power consumption MUST always be less
3233than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3234dynamic or static condition.</li>
3235 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3236TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3237TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3238are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3239 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3240and a magnetometer sensor is also included.</li>
3241</ul>
3242
3243<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3244
3245
3246<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3247device does include a 3-axis magnetometer, it:</p>
3248
3249<ul>
3250 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3251TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3252strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3253 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3254report events up to at least 50 Hz.</li>
3255 <li>MUST comply with the Android sensor coordinate system as detailed in the
3256Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3257 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3258saturating.</li>
3259 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3260below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3261and static (magnet-induced) magnetic fields.</li>
3262 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3263equal or denser than 0.2 &micro;.</li>
3264 <li>SHOULD be temperature compensated.</li>
3265 <li>MUST support online calibration and compensation of the hard iron bias, and
3266preserve the compensation parameters between device reboots.</li>
3267 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3268while in use or during the production of the device.</li>
3269 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3270collected over a period of at least 3 seconds at the fastest sampling rate, no
3271greater than 0.5 &micro;T.</li>
3272 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3273sensor and a gyroscope sensor is also included.</li>
3274 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3275sensor is also implemented. However if implemented, it MUST consume less than
327610 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3277mode at 10 Hz.</li>
3278</ul>
3279
3280<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3281
3282
3283<p>Device implementations SHOULD include a GPS receiver. If a device
3284implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3285
3286<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3287
3288
3289<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3290Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3291also included. If a device implementation includes a gyroscope, it:</p>
3292
3293<ul>
3294 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3295TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3296strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3297 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3298 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3299 Android Watch devices as such devices have a stricter power constraint and
3300 100 Hz for all other device types.</li>
3301 <li>SHOULD report events up to at least 200 Hz.</li>
3302 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
330316-bits or more.</li>
3304 <li>MUST be temperature compensated.</li>
3305 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3306parameters between device reboots.</li>
3307 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3308or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3309be constrained by this value. In other words, if you measure the variance of
3310the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3311 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3312sensor and a magnetometer sensor is also included.</li>
3313 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3314TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3315TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3316are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3317</ul>
3318
3319<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3320
3321
3322<p>Device implementations SHOULD include a barometer (ambient air pressure
3323sensor). If a device implementation includes a barometer, it:</p>
3324
3325<ul>
3326 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3327 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3328 <li>MUST have adequate precision to enable estimating altitude.</li>
3329 <li>MUST be temperature compensated.</li>
3330</ul>
3331
3332<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3333
3334
3335<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3336If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3337measure the ambient (room) temperature in degrees Celsius.</p>
3338
3339<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3340present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3341temperature of the device CPU, and it MUST NOT measure any other temperature.
3342Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3343
3344<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3345
3346
3347<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3348
3349<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3350
3351
3352<p>Device implementations MAY include a proximity sensor. Devices that can make a
3353voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3354SHOULD include a proximity sensor. If a device implementation does include a
3355proximity sensor, it:</p>
3356
3357<ul>
3358 <li>MUST measure the proximity of an object in the same direction as the screen.
3359That is, the proximity sensor MUST be oriented to detect objects close to the
3360screen, as the primary intent of this sensor type is to detect a phone in use
3361by the user. If a device implementation includes a proximity sensor with any
3362other orientation, it MUST NOT be accessible through this API.</li>
3363 <li>MUST have 1-bit of accuracy or more.</li>
3364</ul>
3365
3366<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3367
3368
3369<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3370
3371
3372<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3373to hardware related to placing voice calls and sending SMS messages via a GSM
3374or CDMA network. While these voice calls may or may not be packet-switched,
3375they are for the purposes of Android considered independent of any data
3376connectivity that may be implemented using the same network. In other words,
3377the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3378calls and SMS. For instance, device implementations that cannot place calls or
3379send/receive SMS messages MUST NOT report the android.hardware.telephony
3380feature or any subfeatures, regardless of whether they use a cellular network
3381for data connectivity.</p>
3382
3383<p>Android MAY be used on devices that do not include telephony hardware. That is,
3384Android is compatible with devices that are not phones. However, if a device
3385implementation does include GSM or CDMA telephony, it MUST implement full
3386support for the API for that technology. Device implementations that do not
3387include telephony hardware MUST implement the full APIs as no-ops.</p>
3388
3389<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3390
3391<div class="note">
3392<p>Android Television device implementations MUST include Wi-Fi support.</p>
3393</div>
3394
3395
3396<p>Android Television device implementations MUST include support for one or more
3397forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3398implementation SHOULD include support for one or more forms of 802.11. If a
3399device implementation does include support for 802.11 and exposes the
3400functionality to a third-party application, it MUST implement the corresponding
3401Android API and:</p>
3402
3403<ul>
3404 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3405 <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>
3406 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3407(224.0.0.251) at any time of operation including when the screen is not in an
3408active state.</li>
3409</ul>
3410
3411<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3412
3413
3414<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3415peer-to-peer). If a device implementation does include support for Wi-Fi
3416Direct, it MUST implement the corresponding Android API as described in the SDK
3417documentation [<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>
3418
3419<ul>
3420 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3421 <li>MUST support regular Wi-Fi operation.</li>
3422 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3423</ul>
3424
3425<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3426
3427<div class="note">
3428<p>Android Television device implementations MUST include support for Wi-Fi
3429Tunneled Direct Link Setup (TDLS).</p>
3430</div>
3431
3432
3433<p>Android Television device implementations MUST include support for Wi-Fi
3434Tunneled Direct Link Setup (TDLS) and other types of Android device
3435implementations SHOULD include support for Wi-Fi TDLS as described in the
3436Android 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
3437by the WiFiManager API, the device:</p>
3438
3439<ul>
3440 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3441 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3442than going through the Wi-Fi access point.</li>
3443</ul>
3444
3445<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3446
3447<div class="note">
3448<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3449Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3450</div>
3451
3452
3453<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
3454Energy MUST declare the relevant platform features (android.hardware.bluetooth
3455and android.hardware.bluetooth_le respectively) and implement the platform
3456APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3457as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3458device implementations MUST support Bluetooth and Bluetooth LE. </p>
3459
3460<p>Device implementations including support for Bluetooth Low Energy:</p>
3461
3462<ul>
3463 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3464 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3465described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3466 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3467implementing 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
3468android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3469 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3470if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3471android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3472 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3473MUST report &lsquo;false&rsquo; whenever queried via the
3474android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3475</ul>
3476
3477<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3478
3479
3480<p>Device implementations SHOULD include a transceiver and related hardware for
3481Near-Field Communications (NFC). If a device implementation does include NFC
3482hardware and plans to make it available to third-party apps, then it:</p>
3483
3484<ul>
3485 <li>MUST report the android.hardware.nfc feature from the
3486android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3487 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3488standards:
3489 <ul>
3490 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3491Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3492following NFC standards:
3493 <ul>
3494 <li>NfcA (ISO14443-3A)</li>
3495 <li>NfcB (ISO14443-3B)</li>
3496 <li>NfcF (JIS 6319-4)</li>
3497 <li>IsoDep (ISO 14443-4)</li>
3498 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3499 </ul>
3500 <li>SHOULD be capable of reading and writing NDEF messages via the following NFC
3501standards. Note that while the NFC standards below are stated as SHOULD, the
3502Compatibility Definition for a future version is planned to change these to
3503MUST. These standards are optional in this version but will be required in
3504future versions. Existing and new devices that run this version of Android are <strong>very strongly encouraged</strong> to meet these requirements now so they will be able to upgrade to the future platform releases.</li>
3505 <ul>
3506 <li>NfcV (ISO 15693)</li>
3507 </ul></li>
3508 <li>MUST be capable of transmitting and receiving data via the following
3509peer-to-peer standards and protocols:
3510 <ul>
3511 <li>ISO 18092</li>
3512 <li>LLCP 1.0 (defined by the NFC Forum)</li>
3513 <li>SDP 1.0 (defined by the NFC Forum)</li>
3514 <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>
3515 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3516 </ul></li>
3517 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3518 <ul>
3519 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3520default SNEP server MUST be dispatched to applications using the
3521android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3522MUST NOT disable dispatch of incoming NDEF message.</li>
3523 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3524settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3525 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3526processed the same way as the SNEP default server.</li>
3527 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3528default SNEP server when Android Beam is enabled. If no default SNEP server is
3529found then the client MUST attempt to send to an NPP server.</li>
3530 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3531android.nfc.NfcAdapter.setNdefPushMessage, and
3532android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3533android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3534 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3535sending outbound P2P NDEF messages.</li>
3536 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3537using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3538 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3539Bluetooth Object Push Profile. Device implementations MUST support connection
3540handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3541implementing 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
3542LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3543handover request/select records over NFC, and it MUST use the Bluetooth Object
3544Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3545remain compatible with Android 4.1 devices), the implementation SHOULD still
3546accept SNEP GET requests for exchanging the handover request/select records
3547over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3548for performing connection handover.</li>
3549 </ul></li>
3550 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3551 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3552active and the lock-screen unlocked.</li>
3553</ul>
3554</ul>
3555
3556<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3557Forum specifications cited above.)</p>
3558
3559<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3560device implementation does include an NFC controller chipset capable of HCE and
3561Application ID (AID) routing, then it:</p>
3562
3563<ul>
3564 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3565 <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>
3566</ul>
3567
3568<p>Additionally, device implementations MAY include reader/writer support for the
3569following MIFARE technologies.</p>
3570
3571<ul>
3572 <li>MIFARE Classic</li>
3573 <li>MIFARE Ultralight</li>
3574 <li>NDEF on MIFARE Classic</li>
3575</ul>
3576
3577<p>Note that Android includes APIs for these MIFARE types. If a device
3578implementation supports MIFARE in the reader/writer role, it:</p>
3579
3580<ul>
3581 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3582 <li>MUST report the feature com.nxp.mifare from the
3583android.content.pm.PackageManager.hasSystemFeature() meth<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">od [Resources, 53]</a>. Note that this is not a standard Android feature and as such does not appear
3584as a constant on the PackageManager class.</li>
3585 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3586feature unless it also implements general NFC support as described in this
3587section.</li>
3588</ul>
3589
3590<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3591the android.hardware.nfc feature from the
3592android.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>
3593
3594<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3595protocol-independent data representation format, device implementations MUST
3596implement these APIs even if they do not include support for NFC or declare the
3597android.hardware.nfc feature.</p>
3598
3599<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3600
3601
3602<p>Device implementations MUST include support for one or more forms of data
3603networking. Specifically, device implementations MUST include support for at
3604least one data standard capable of 200Kbit/sec or greater. Examples of
3605technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3606Ethernet, Bluetooth PAN, etc.</p>
3607
3608<p>Device implementations where a physical networking standard (such as Ethernet)
3609is the primary data connection SHOULD also include support for at least one
3610common wireless data standard, such as 802.11 (Wi-Fi).</p>
3611
3612<p>Devices MAY implement more than one form of data connectivity.</p>
3613
3614<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3615
3616
3617<p>Device implementations MUST have the master auto-sync setting on by default so
3618that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3619
3620<h2 id="7_5_cameras">7.5. Cameras</h2>
3621
3622
3623<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3624front-facing camera. A rear-facing camera is a camera located on the side of
3625the device opposite the display; that is, it images scenes on the far side of
3626the device, like a traditional camera. A front-facing camera is a camera
3627located on the same side of the device as the display; that is, a camera
3628typically used to image the user, such as for video conferencing and similar
3629applications.</p>
3630
3631<p>If a device implementation includes at least one camera, it SHOULD be possible
3632for an application to simultaneously allocate 3 bitmaps equal to the size of
3633the images produced by the largest-resolution camera sensor on the device.</p>
3634
3635<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3636
3637
3638<p>Device implementations SHOULD include a rear-facing camera. If a device
3639implementation includes at least one rear-facing camera, it:</p>
3640
3641<ul>
3642 <li>MUST report the feature flag android.hardware.camera and
3643android.hardware.camera.any.</li>
3644 <li>MUST have a resolution of at least 2 megapixels.</li>
3645 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3646the camera driver (transparent to application software).</li>
3647 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3648 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3649lit while an android.hardware.Camera.PreviewCallback instance has been
3650registered on a Camera preview surface, unless the application has explicitly
3651enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3652of a Camera.Parameters object. Note that this constraint does not apply to the
3653device&rsquo;s built-in system camera application, but only to third-party
3654applications using Camera.PreviewCallback.</li>
3655</ul>
3656
3657<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3658
3659
3660<p>Device implementations MAY include a front-facing camera. If a device
3661implementation includes at least one front-facing camera, it:</p>
3662
3663<ul>
3664 <li>MUST report the feature flag android.hardware.camera.any and
3665android.hardware.camera.front.</li>
3666 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3667 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3668camera API in Android has specific support for front-facing cameras and device
3669implementations MUST NOT configure the API to to treat a front-facing camera as
3670the default rear-facing camera, even if it is the only camera on the device.</li>
3671 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3672cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3673 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3674CameraPreview, as follows:
3675 <ul>
3676 <li>If the device implementation is capable of being rotated by user (such as
3677automatically via an accelerometer or manually via user input), the camera
3678preview MUST be mirrored horizontally relative to the device&rsquo;s current
3679orientation.</li>
3680 <li>If the current application has explicitly requested that the Camera display be
3681rotated 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
3682orientation specified by the application.</li>
3683 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3684axis.</li>
3685 </ul></li>
3686 <li>MUST mirror the image displayed by the postview in the same manner as the
3687camera preview image stream. If the device implementation does not support
3688postview, this requirement obviously does not apply.</li>
3689 <li>MUST NOT mirror the final captured still image or video streams returned to
3690application callbacks or committed to media storage.</li>
3691</ul>
3692
3693<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3694
3695
3696<p>Device implementations with USB host mode MAY include support for an external
3697camera that connects to the USB port. If a device includes support for an
3698external camera, it:</p>
3699
3700<ul>
3701 <li>MUST declare the platform feature android.hardware.camera.external and
3702android.hardware camera.any.</li>
3703 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3704 <li>MAY support multiple cameras.</li>
3705</ul>
3706
3707<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3708high-quality unencoded streams (i.e. raw or independently compressed picture
3709streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3710unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3711device implementation.</p>
3712
3713<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3714
3715
3716<p>Android includes two API packages to access the camera, the newer
3717android.hardware.camera2 API expose lower-level camera control to the app,
3718including efficient zero-copy burst/streaming flows and per-frame controls of
3719exposure, gain, white balance gains, color conversion, denoising, sharpening,
3720and more.</p>
3721
3722<p>The older API package, android.hardware.Camera, is marked as deprecated in
3723Android 5.0 but as it should still be available for apps to use Android device
3724implementations MUST ensure the continued support of the API as described in
3725this section and in the Android SDK.</p>
3726
3727<p>Device implementations MUST implement the following behaviors for the
3728camera-related APIs, for all available cameras:</p>
3729
3730<ul>
3731 <li>If an application has never called
3732android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3733use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3734application callbacks.</li>
3735 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3736and the system calls the onPreviewFrame() method when the preview format is
3737YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3738be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3739 <li>For android.hardware.Camera, device implementations MUST support the YV12
3740format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3741camera previews for both front- and rear-facing cameras. (The hardware video
3742encoder and camera may use any native pixel format, but the device
3743implementation MUST support conversion to YV12.)</li>
3744 <li>For android.hardware.camera2, device implementations must support the
3745android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3746formats as outputs through the android.media.ImageReader API.</li>
3747</ul>
3748
3749<p>Device implementations MUST still implement the full Camera API included in the
3750Android 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
3751capabilities. For instance, cameras that lack autofocus MUST still call any
3752registered android.hardware.Camera.AutoFocusCallback instances (even though
3753this has no relevance to a non-autofocus camera.) Note that this does apply to
3754front-facing cameras; for instance, even though most front-facing cameras do
3755not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3756
3757<p>Device implementations MUST recognize and honor each parameter name defined as
3758a constant on the android.hardware.Camera.Parameters class, if the underlying
3759hardware supports the feature. If the device hardware does not support a
3760feature, the API must behave as documented. Conversely, device implementations
3761MUST NOT honor or recognize string constants passed to the
3762android.hardware.Camera.setParameters() method other than those documented as
3763constants on the android.hardware.Camera.Parameters. That is, device
3764implementations MUST support all standard Camera parameters if the hardware
3765allows, and MUST NOT support custom Camera parameter types. For instance,
3766device implementations that support image capture using high dynamic range
3767(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>
3768
3769<p>Because not all device implementations can fully support all the features of
3770the android.hardware.camera2 API, device implementations MUST report the proper
3771level of support with the android.info.supportedHardwareLevel property as
3772described 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>
3773
3774<p>Device implementations MUST also declare its Individual camera capabilities of
3775android.hardware.camera2 via the android.request.availableCapabilities property
3776and 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>
3777
3778<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3779whenever a new picture is taken by the camera and the entry of the picture has
3780been added to the media store.</p>
3781
3782<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3783whenever a new video is recorded by the camera and the entry of the picture has
3784been added to the media store.</p>
3785
3786<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3787
3788
3789<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3790long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3791when the device is held in the landscape orientation, cameras MUST capture
3792images in the landscape orientation. This applies regardless of the device&rsquo;s
3793natural orientation; that is, it applies to landscape-primary devices as well
3794as portrait-primary devices.</p>
3795
3796<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3797
3798
3799<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3800
3801<div class="note">
3802<p>Android Television devices MUST have at least 5GB of non-volatile storage
3803available for application private data.</p>
3804</div>
3805
3806
3807<p>The memory available to the kernel and userspace on device implementations MUST
3808be at least equal or larger than the minimum values specified by the following
3809table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3810<table>
3811 <tr>
3812 <th>Density and screen size</th>
3813 <th>32-bit device</th>
3814 <th>64-bit device</th>
3815 </tr>
3816 <tr>
3817 <td>Android Watch devices (due to smaller screens)</td>
3818 <td>416MB</td>
3819 <td>Not applicable</td>
3820 </tr>
3821 <tr>
3822 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3823 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3824 <li class="table_list">mdpi or lower on large screens</li>
3825 <li class="table_list">ldpi or lower on extra large screens</li>
3826 </ul></td>
3827 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3828 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3829 </tr>
3830 <tr>
3831 <td><ul>
3832 <li class="table_list">xhdpi or higher on small/normal screens</li>
3833 <li class="table_list">hdpi or higher on large screens</li>
3834 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3835 <td>512MB</td>
3836 <td>832MB</td>
3837 </tr>
3838 <tr>
3839 <td><ul>
3840 <li class="table_list">400dpi or higher on small/normal screens</li>
3841 <li class="table_list">xhdpi or higher on large screens</li>
3842 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3843 <td>896MB</td>
3844 <td>1280MB</td>
3845 </tr>
3846 <tr>
3847 <td><ul>
3848 <li class="table_list">560dpi or higher on small/normal screens</li>
3849 <li class="table_list">400dpi or higher on large screens</li>
3850 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3851 <td>1344MB</td>
3852 <td>1824MB</td>
3853 </tr>
3854</table>
3855
3856
3857<p>The minimum memory values MUST be in addition to any memory space already
3858dedicated to hardware components such as radio, video, and so on that is not
3859under the kernel&rsquo;s control.</p>
3860
3861<p>Device implementations with less than 512MB of memory available to the kernel
3862and userspace, unless an Android Watch, MUST return the value "true" for
3863ActivityManager.isLowRamDevice().</p>
3864
3865<p>Android Television devices MUST have at least 5GB and other device
3866implementations MUST have at least 1.5GB of non-volatile storage available for
3867application private data. That is, the /data partition MUST be at least 5GB for
3868Android Television devices and at least 1.5GB for other device implementations.
3869Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3870they will be able to upgrade to the future platform releases.</p>
3871
3872<p>The Android APIs include a Download Manager that applications MAY use to
3873download 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
3874downloading individual files of at least 100MB in size to the default &ldquo;cache"
3875location.</p>
3876
3877<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3878
3879
3880<p>Device implementations MUST offer shared storage for applications also often
3881referred as &ldquo;shared external storage&rdquo;. </p>
3882
3883<p>Device implementations MUST be configured with shared storage mounted by
3884default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3885path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3886to the actual mount point.</p>
3887
3888<p>Device implementations MAY have hardware for user-accessible removable storage,
3889such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3890shared storage requirement, the device implementation:</p>
3891
3892<ul>
3893 <li>MUST implement a toast or pop-up user interface warning the user when there is
3894no SD card.</li>
3895 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3896and other material available at time of purchase that the SD card has to be
3897separately purchased.</li>
3898 <li>MUST mount the SD card by default.</li>
3899</ul>
3900
3901<p>Alternatively, device implementations MAY allocate internal (non-removable)
3902storage as shared storage for apps as included in the upstream Android Open
3903Source Project; device implementations SHOULD use this configuration and
3904software implementation. If a device implementation uses internal
3905(non-removable) storage to satisfy the shared storage requirement, that storage
3906MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3907symbolic link to the physical location if it is mounted elsewhere).</p>
3908
3909<p>Device implementations MUST enforce as documented the
3910android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3911Shared storage MUST otherwise be writable by any application that obtains that
3912permission.</p>
3913
3914<p>Device implementations that include multiple shared storage paths (such as both
3915an SD card slot and shared internal storage) MUST NOT allow Android
3916applications to write to the secondary external storage, except for their
3917package-specific directories on the secondary external storage, but SHOULD
3918expose content from both storage paths transparently through Android&rsquo;s media
3919scanner service and android.provider.MediaStore.</p>
3920
3921<p>Regardless of the form of shared storage used, if the device implementation
3922has a USB port with USB peripheral mode support, it MUST provide some mechanism
3923to access the contents of shared storage from a host computer. Device
3924implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3925to satisfy this requirement. If the device implementation supports Media
3926Transfer Protocol, it:</p>
3927
3928<ul>
3929 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3930[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3931 <li>SHOULD report a USB device class of 0x00.</li>
3932 <li>SHOULD report a USB interface name of 'MTP'.</li>
3933</ul>
3934
3935<h2 id="7_7_usb">7.7. USB</h2>
3936
3937
3938<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3939USB host mode.</p>
3940
3941<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3942
3943<ul>
3944 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3945-C USB port.</li>
3946 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3947new Android devices are <strong>very strongly encouraged to meet these requirements</strong> so they will be able to upgrade to the future platform releases.</li>
3948 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3949SHOULD either locate the port on the bottom of the device (according to natural
3950orientation) or enable software screen rotation for all apps (including home
3951screen), so that the display draws correctly when the device is oriented with
3952the port at bottom. Existing and new Android devices are <strong>very strongly encouraged to meet these requirements</strong> so they will be able to upgrade to future platform releases.</li>
3953 <li>It MUST allow a USB host connected with the Android device to access the
3954contents of the shared storage volume using either USB mass storage or Media
3955Transfer Protocol.</li>
3956 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3957documented in the Android SDK documentation, and if it is an Android Handheld
3958device it MUST implement the AOA API. Device implementations implementing the
3959AOA specification:
3960 <ul>
3961 <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>
3962 <li>MUST implement the USB audio class as documented in the Android SDK
3963documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3964 </ul></li>
3965 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3966as 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>very strongly encouraged to meet these requirements</strong> so they will be able to upgrade to the future platform releases.</li>
3967 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3968the value of android.os.Build.SERIAL.</li>
3969</ul>
3970
3971<p>If a device implementation includes a USB port supporting host mode, it:</p>
3972
3973<ul>
3974 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3975 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3976cables adapting the port to a standard type-A or type-C USB port.</li>
3977 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3978adapting the port to a standard type-A or type-C USB port.</li>
3979 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3980documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3981 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3982MUST 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>
3983 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3984as 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>
3985</ul>
3986
3987<h2 id="7_8_audio">7.8. Audio</h2>
3988
3989
3990<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3991
3992<div class="note">
3993<p>Android Handheld, Watch, and Automotive implementations MUST include a
3994microphone.</p>
3995</div>
3996
3997
3998<p>Device implementations MAY omit a microphone. However, if a device
3999implementation omits a microphone, it MUST NOT report the
4000android.hardware.microphone feature constant, and MUST implement the audio
4001recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4002
4003<ul>
4004 <li>MUST report the android.hardware.microphone feature constant
4005 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
4006 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
4007</ul>
4008
4009<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4010
4011<div class="note">
4012<p>Android Watch devices MAY include an audio output.</p>
4013</div>
4014
4015<p>Device implementations including a speaker or with an audio/multimedia output
4016port for an audio output peripheral as a headset or an external speaker:</p>
4017
4018<ul>
4019 <li>MUST report the android.hardware.audio.output feature constant.</li>
4020 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4021 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4022</ul>
4023
4024<p>Conversely, if a device implementation does not include a speaker or audio
4025output port, it MUST NOT report the android.hardware.audio output feature, and
4026MUST implement the Audio Output related APIs as no-ops at least. </p>
4027
4028<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4029other types of Android device implementations MUST have an audio output and
4030declare android.hardware.audio.output.</p>
4031
4032<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4033
4034
4035<p>In order to be compatible with the headsets and other audio accessories using
4036the 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
4037one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4038implementation has a 4 conductor 3.5mm audio jack, it:</p>
4039
4040<ul>
4041 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4042microphone, and SHOULD support audio recording from stereo headsets with a
4043microphone.</li>
4044 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4045audio plugs with the OMTP pin-out order.</li>
4046 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4047the device implementation supports a microphone, and broadcast the
4048android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4049 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4050ranges of equivalent impedance between the microphone and ground conductors on
4051the audio plug:
4052 <ul>
4053 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
4054 <li><strong>210&#45;290 Ohm</strong>:<strong> </strong>KEYCODE_VOLUME_UP</li>
4055 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4056 </ul></li>
4057 <li>SHOULD support the detection and mapping to the keycode for the following range
4058of equivalent impedance between the microphone and ground conductors on the
4059audio plug:
4060 <ul>
4061 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4062 </ul></li>
4063 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4064contacts on plug are touching their relevant segments on the jack.</li>
4065 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4066speaker impedance.</li>
4067 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4068</ul>
4069
4070<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4071
4072
4073<p>Some minimum performance criterias are critical to the user experience and
4074impacts the baseline assumptions developers would have when developing an app.
4075Android Watch devices SHOULD and other type of device implementations MUST meet
4076the following criteria:</p>
4077
4078<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4079
4080
4081<p>Device implementations MUST provide a smooth user interface by ensuring a
4082consistent frame rate and response times for applications and games. Device
4083implementations MUST meet the following requirements: </p>
4084
4085<ul>
4086 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4087often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4088 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4089list of 10K list entries as defined by the Android Compatibility Test Suite
4090(CTS) in less than 36 secs.</li>
4091 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4092application after it has been launched MUST take less than 1 second.</li>
4093</ul>
4094
4095<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4096
4097
4098<p>Device implementations MUST ensure internal storage file access performance consistency for read
4099and write operations. </p>
4100
4101<ul>
4102 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4103for a 256MB file using 10MB write buffer.</li>
4104 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4105256MB file using 4KB write buffer.</li>
4106 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4107a 256MB file using 10MB write buffer.</li>
4108 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4109256MB file using 4KB write buffer.</li>
4110</ul>
4111
4112<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4113
4114
4115<p>Device implementations MUST implement a security model consistent with the
4116Android platform security model as defined in Security and Permissions
4117reference 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
4118installation of self-signed applications without requiring any additional
4119permissions/certificates from any third parties/authorities. Specifically,
4120compatible devices MUST support the security mechanisms described in the follow
4121subsections.</p>
4122
4123<h2 id="9_1_permissions">9.1. Permissions</h2>
4124
4125
4126<p>Device implementations MUST support the Android permissions model as defined in
4127the 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
4128described in the SDK documentation; no permissions may be omitted, altered, or
4129ignored. Implementations MAY add additional permissions, provided the new
4130permission ID strings are not in the android.* namespace.</p>
4131
4132<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4133
4134
4135<p>Device implementations MUST support the Android application sandbox model, in
4136which each application runs as a unique Unixstyle UID and in a separate
4137process. Device implementations MUST support running multiple applications as
4138the same Linux user ID, provided that the applications are properly signed and
4139constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4140
4141<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4142
4143
4144<p>Device implementations MUST support the Android file access permissions model
4145as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4146
4147<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4148
4149
4150<p>Device implementations MAY include runtime environments that execute
4151applications using some other software or technology than the Dalvik Executable
4152Format or native code. However, such alternate execution environments MUST NOT
4153compromise the Android security model or the security of installed Android
4154applications, as described in this section.</p>
4155
4156<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4157standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4158
4159<p>Alternate runtimes MUST NOT be granted access to resources protected by
4160permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4161&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4162
4163<p>Alternate runtimes MUST NOT permit applications to make use of features
4164protected by Android permissions restricted to system applications.</p>
4165
4166<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4167alternate runtimes:</p>
4168
4169<ul>
4170 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4171Linux user IDs, etc.).</li>
4172 <li>MAY provide a single Android sandbox shared by all applications using the
4173alternate runtime.</li>
4174 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4175sandbox of any other app installed on the device, except through the standard
4176Android mechanisms of shared user ID and signing certificate.</li>
4177 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4178corresponding to other Android applications.</li>
4179 <li>MUST NOT be launched with, be granted, or grant to other applications any
4180privileges of the superuser (root), or of any other user ID.</li>
4181</ul>
4182
4183<p>The .apk files of alternate runtimes MAY be included in the system image of a
4184device implementation, but MUST be signed with a key distinct from the key used
4185to sign other applications included with the device implementation.</p>
4186
4187<p>When installing applications, alternate runtimes MUST obtain user consent for
4188the Android permissions used by the application. If an application needs to
4189make use of a device resource for which there is a corresponding Android
4190permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4191user that the application will be able to access that resource. If the runtime
4192environment does not record application capabilities in this manner, the
4193runtime environment MUST list all permissions held by the runtime itself when
4194installing any application using that runtime.</p>
4195
4196<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4197
4198<div class="note">
4199<p>This feature is optional for all device types.</p>
4200</div>
4201
4202
4203<p>Android includes support for multiple users and provides support for full user
4204isolation [<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
4205the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4206
4207<ul>
4208 <li>Device implementations that do not declare the android.hardware.telephony
4209feature flag MUST support restricted profiles, a feature that allows device
4210owners to manage additional users and their capabilities on the device. With
4211restricted profiles, device owners can quickly set up separate environments for
4212additional users to work in, with the ability to manage finer-grained
4213restrictions in the apps that are available in those environments.</li>
4214 <li>Conversely device implementations that declare the android.hardware.telephony
4215feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4216implementation of controls to enable /disable other users from accessing the
4217voice calls and SMS.</li>
4218 <li>Device implementations MUST, for each user, implement a security model
4219consistent with the Android platform security model as defined in Security and
4220Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4221 <li>Device implementations MAY support creating users and managed profiles via the
4222android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4223platform feature flag android.software.managed_users.
4224 <li>Device implementations that declare the feature flag
4225android.software.managed_users MUST use the upstream AOSP icon badge to
4226represent the managed applications and other badge UI elements like Recents &
4227Notifications.</li>
4228 <li>Each user instance on an Android device MUST have separate and isolated
4229external storage directories. Device implementations MAY store multiple users'
4230data on the same volume or filesystem. However, the device implementation MUST
4231ensure that applications owned by and running on behalf a given user cannot
4232list, read, or write to data owned by any other user. Note that removable
4233media, such as SD card slots, can allow one user to access another&rsquo;s data by
4234means of a host PC. For this reason, device implementations that use removable
4235media for the external storage APIs MUST encrypt the contents of the SD card if
4236multiuser is enabled using a key stored only on non-removable media accessible
4237only to the system. As this will make the media unreadable by a host PC, device
4238implementations will be required to switch to MTP or a similar system to
4239provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4240implementations MAY but SHOULD NOT enable multi-user if they use removable
4241media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4242</ul>
4243
4244<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4245
4246
4247<p>Android includes support for warning users of any outgoing premium SMS message
4248[<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
4249carrier that may incur a charge to the user. Device implementations that
4250declare support for android.hardware.telephony MUST warn users before sending a
4251SMS message to numbers identified by regular expressions defined in
4252/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4253Project provides an implementation that satisfies this requirement.</p>
4254
4255<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4256
4257
4258<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4259(SELinux) mandatory access control (MAC) system and other security features in
4260the Linux kernel. SELinux or any other security features, if implemented below
4261the Android framework:</p>
4262
4263<ul>
4264 <li>MUST maintain compatibility with existing applications.</li>
4265 <li>MUST NOT have a visible user interface when a security violation is detected
4266and successfully blocked, but MAY have a visible user interface when an
4267unblocked security violation occurs resulting in a successful exploit.</li>
4268 <li>SHOULD NOT be user or developer configurable.</li>
4269</ul>
4270
4271<p>If any API for configuration of policy is exposed to an application that can
4272affect another application (such as a Device Administration API), the API MUST
4273NOT allow configurations that break compatibility.</p>
4274
4275<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4276if using a kernel other than Linux and meet the following requirements, which
4277are satisfied by the reference implementation in the upstream Android Open
4278Source Project.</p>
4279
4280<p>Device implementations:</p>
4281
4282<ul>
4283 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4284per-domain basis, and MUST configure all domains in enforcing mode. No
4285permissive mode domains are allowed, including domains specific to a
4286device/vendor.</li>
4287 <li>SHOULD load policy from /sepolicy file on the device.</li>
4288 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4289sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4290the policy MUST compile with all neverallow present, for both AOSP SELinux
4291domains as well as device/vendor specific domains.</li>
4292 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4293system image update.</li>
4294</ul>
4295
4296<p>Device implementations SHOULD retain the default SELinux policy provided in the
4297upstream Android Open Source Project, until they have first audited their
4298additions to the SELinux policy. Device implementations MUST be compatible with
4299the upstream Android Open Source Project.</p>
4300
4301<h2 id="9_8_privacy">9.8. Privacy</h2>
4302
4303<p>If the device implements functionality in the system that captures the contents
4304displayed on the screen and/or records the audio stream played on the device,
4305it MUST continuously notify the user whenever this functionality is enabled and
4306actively capturing/recording.</p>
4307
4308<p>If a device implementation has a mechanism that routes network data traffic
4309through a proxy server or VPN gateway by default (for example, preloading a VPN
4310service with android.permission.CONTROL_VPN granted), the device implementation
4311MUST ask for the user's consent before enabling that mechanism.</p>
4312
4313<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4314
4315<div class="note">
4316<p>Optional for Android device implementations without a lock screen.</p>
4317</div>
4318
4319
4320<p>If the device implementation supports a lock screen with PIN (numeric) or
4321PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4322application private data (/data partition), as well
4323as the SD card partition if it is a permanent, non-removable part of the device
4324[<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
4325be enabled all the time after the user has completed the out-of-box experience.
4326While this requirement is stated as SHOULD for this version of the Android
4327platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4328Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4329for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4330be written to storage at any time without being encrypted. Other than when in
4331active use, the encryption key SHOULD be AES encrypted with the lockscreen
4332passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4333If the user has not specified a lockscreen passcode or has disabled use of the
4334passcode for encryption, the system SHOULD use a default passcode to wrap the
4335encryption key. If the device provides a hardware-backed keystore, the password
4336stretching algorithm MUST be cryptographically bound to that keystore. The
4337encryption key MUST NOT be sent off the device (even when wrapped with the user
4338passcode and/or hardware bound key). The upstream Android Open Source project
4339provides a preferred implementation of this feature based on the linux kernel
4340feature dm-crypt.</p>
4341
4342<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4343
4344<p>
4345Verified boot is a feature that guarantees the integrity of the device software.
4346If a device implementation supports the feature, it MUST:
4347<ul>
4348<li>Declare the platform feature flag android.software.verified_boot</li>
4349<li>Perform verification on every boot sequence</li>
4350<li>Start verification from a hardware key that is the root of trust, and go
4351all the way up to the system partition</li>
4352<li>Implement each stage of verification to check the integrity and authenticity
4353of all the bytes in the next stage before executing the code in the next stage</li>
4354<li>Use verification algorithms as strong as current recommendations
4355from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4356</ul>
4357</p>
4358
4359<p>Device implementations SHOULD support verified boot for device integrity.
4360While this requirement is SHOULD for this version of the Android platform,
4361it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4362in future versions of Android. The upstream Android Open Source Project provides
4363a preferred implementation of this feature based on the linux kernel feature dm-verity.
4364</p>
4365
4366<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4367
4368
4369<p>Device implementations MUST pass all tests described in this section.</p>
4370
4371<p>However, note that no software test package is fully comprehensive. For this
4372reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4373preferred implementation of Android available from the Android Open Source
4374Project. This will minimize the risk of introducing bugs that create
4375incompatibilities requiring rework and potential device updates.</p>
4376
4377<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4378
4379
4380<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
4381software on the device. Additionally, device implementers SHOULD use the
4382reference implementation in the Android Open Source tree as much as possible,
4383and MUST ensure compatibility in cases of ambiguity in CTS and for any
4384reimplementations of parts of the reference source code.</p>
4385
4386<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4387may itself contain bugs. The CTS will be versioned independently of this
4388Compatibility Definition, and multiple revisions of the CTS may be released for
4389Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4390at the time the device software is completed.</p>
4391
4392<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4393
4394
4395<p>Device implementations MUST correctly execute all applicable cases in the CTS
4396Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4397is intended to be run by a human operator to test functionality that cannot be
4398tested by an automated system, such as correct functioning of a camera and
4399sensors.</p>
4400
4401<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4402that is optional. Device implementations MUST pass all tests for hardware that
4403they possess; for instance, if a device possesses an accelerometer, it MUST
4404correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4405for features noted as optional by this Compatibility Definition Document MAY be
4406skipped or omitted.</p>
4407
4408<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4409above. However, since many builds are very similar, device implementers are not
4410expected to explicitly run the CTS Verifier on builds that differ only in
4411trivial ways. Specifically, device implementations that differ from an
4412implementation that has passed the CTS Verifier only by the set of included
4413locales, branding, etc. MAY omit the CTS Verifier test.</p>
4414
4415<h1 id="11_updatable_software">11. Updatable Software</h1>
4416
4417
4418<p>Device implementations MUST include a mechanism to replace the entirety of the
4419system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4420device restart MAY be required.</p>
4421
4422<p>Any method can be used, provided that it can replace the entirety of the
4423software preinstalled on the device. For instance, any of the following
4424approaches will satisfy this requirement:</p>
4425
4426<ul>
4427 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4428 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4429 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4430</ul>
4431
4432<p>However, if the device implementation includes support for an unmetered data
4433connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4434
4435<ul>
4436<li>Android Automotive implementations SHOULD support OTA downloads with offline
4437update via reboot.</li>
4438<li>All other device implementations MUST support OTA downloads with offline
4439update via reboot.</li>
4440</ul>
4441
4442<p>The update mechanism used MUST support updates without wiping user data. That
4443is, the update mechanism MUST preserve application private data and application
4444shared data. Note that the upstream Android software includes an update
4445mechanism that satisfies this requirement.</p>
4446
4447<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4448update mechanism SHOULD support verifying that the system image is binary
4449identical to expected result following an OTA. The block-based OTA
4450implementation in the upstream Android Open Source Project, added since Android
44515.1, satisfies this requirement.</p>
4452
4453<p>If an error is found in a device implementation after it has been released but
4454within its reasonable product lifetime that is determined in consultation with
4455the Android Compatibility Team to affect the compatibility of third-party
4456applications, the device implementer MUST correct the error via a software
4457update available that can be applied per the mechanism just described.</p>
4458
4459<h1 id="12_document_changelog">12. Document Changelog</h1>
4460
4461
4462<p>The following table contains a summary of the changes to the Compatibility
4463Definition in this release. </p>
4464<table>
4465 <tr>
4466 <th>Section</th>
4467 <th>Summary of change</th>
4468 </tr>
4469 <tr>
4470 <td>2. Device Types</td>
4471 <td>Added definition for Android automotive implementation.</td>
4472 </tr>
4473 <tr>
4474 <td>2.1 Device Configurations</td>
4475 <td>Added column for Android automotive implementation.</td>
4476 </tr>
4477 <tr>
4478 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4479 <td>New section added.</td>
4480 </tr>
4481 <tr>
4482 <td>3.4.1. WebView Compatibility</td>
4483 <td>Updated webview user agent string requirement to accomodate upstream
4484 implementation change.</td>
4485 </tr>
4486 <tr>
4487 <td>3.4.2. Browser compatibility</td>
4488 <td>Added Android automotive implementations as another case that MAY omit a
4489 browser application.</td>
4490 </tr>
4491 <tr>
4492 <td>3.7. Runtime Compatibility</td>
4493 <td>Updated required runtime heap size for smaller screens and added requirement
4494 for the new dpi bucket (280dpi).</td>
4495 </tr>
4496 <tr>
4497 <td>3.8.3. Notifications</td>
4498 <td>Clarified notification requirement for Android Watch, Television and
4499 Automotive implementations.</td>
4500 </tr>
4501 <tr>
4502 <td>3.8.10. Lock Screen Media Control<</td>
4503 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4504 </tr>
4505 <tr>
4506 <td>3.8.13. Unicode and font</td>
4507 <td>Relaxed Emoji character input method requirement.</td>
4508 </tr>
4509 <tr>
4510 <td>3.9. Device Administration</td>
4511 <td>Clarified condition when the full range of device administration policies
4512 has to be supported.</td>
4513 </tr>
4514 <tr>
4515 <td>3.10. Accessibility</td>
4516 <td>Added Android automotive requirements.</td>
4517 </tr>
4518 <tr>
4519 <td>3.11. Text-To-Speech</td>
4520 <td>Added Android automotive requirements.</td>
4521 </tr>
4522 <tr>
4523 <td>5.1. Media Codecs</td>
4524 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4525 </tr>
4526 <tr>
4527 <td>5.1.3 Video Codecs</td>
4528 <td>Added Android automotive requirements.</td>
4529 </tr>
4530 <tr>
4531 <td>7.1.1.3. Screen Density</td>
4532 <td>Added a new screen dpi (280dpi).</td>
4533 </tr>
4534 <tr>
4535 <td>7.1.5. Legacy Application Compatibility Mode</td>
4536 <td>Added Android automotive requirements.</td>
4537 </tr>
4538 <tr>
4539 <td>7.2 Input Devices</td>
4540 <td>Added general introduction statement.</td>
4541 </tr>
4542 <tr>
4543 <td>7.2.1. Keyboard</td>
4544 <td>Added Android Automotive requirements.</td>
4545 </tr>
4546 <tr>
4547 <td>7.2.3. Navigation Keys</td>
4548 <td>Added Android Automotive requirements.</td>
4549 </tr>
4550 <tr>
4551 <td>7.3.1. Accelerometer</td>
4552 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4553 </tr>
4554 <tr>
4555 <td>7.3.4. Gyroscope</td>
4556 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4557 </tr>
4558 <tr>
4559 <td>7.4.3 Bluetooth</td>
4560 <td>Added Android Automotive requirements.</td>
4561 </tr>
4562 <tr>
4563 <td>7.4.4. Near-Field Communications</td>
4564 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4565 </tr>
4566 <tr>
4567 <td>7.6.1. Minimum Memory and Storage</td>
4568 <td>Updated minimum memory requirements for lower resulution screen devices
4569 and added hard-limit requirement isLowRamDevice().</td>
4570 </tr>
4571 <tr>
4572 <td>7.6.2. Application Shared Storage</td>
4573 <td>Updated requirements when support for host machine access is mandatory.</td>
4574 </tr>
4575 <tr>
4576 <td>7.8.1. Microphone</td>
4577 <td>Added Android Automotive requirements.</td>
4578 </tr>
4579 <tr>
4580 <td>8.2. File I/O Access Performance</td>
4581 <td>Clarified requirements.</td>
4582 </tr>
4583 <tr>
4584 <td>9.8. Privacy</td>
4585 <td>Added privacy requirement for preloaded VPNs.</td>
4586 </tr>
4587 <tr>
4588 <td>9.9. Full-Disk Encryption</td>
4589 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4590 </tr>
4591 <tr>
4592 <td>9.10. Verified Boot</td>
4593 <td>Clarified definition of verified boot.</td>
4594 </tr>
4595 <tr>
4596 <td>11. Updatable Software</td>
4597 <td>Clarified the OTA download requirement is allowed but not mandatory for
4598 Android Automotive implementations.</td>
4599 </tr>
4600</table>
4601
4602
4603<h1 id="13_contact_us">13. Contact Us</h1>
4604
4605
4606<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
4607does not cover.</p>
4608
4609<h1 id="14_resources">14. Resources</h1>
4610
4611
4612<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4613
4614<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4615
4616<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>
4617
4618<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>
4619
4620<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4621
4622<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>
4623
4624<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>
4625
4626<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>
4627
4628<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>
4629
4630<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>
4631
4632<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>
4633
4634<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>
4635
4636<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4637
4638<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4639
4640<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>
4641
4642<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>
4643
4644<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4645
4646<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4647
4648<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4649
4650<p>20. Dalvik Executable Format and bytecode specification: available in the
4651Android source code, at dalvik/docs</p>
4652
4653<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>
4654
4655<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>
4656
4657<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>
4658
4659<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>
4660
4661<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4662
4663<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>
4664
4665<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>
4666
4667<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>
4668
4669<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>
4670
4671<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>
4672
4673<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>
4674
4675<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>
4676
4677<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>
4678
4679<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>
4680
4681<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>
4682
4683<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>
4684
4685<p>37. Settings.Secure LOCATION_MODE:</p>
4686
4687<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>
4688
4689<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>
4690
4691<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>
4692
4693<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>
4694
4695<p>41. Android Device Owner App:</p>
4696
4697<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>
4698
4699<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>
4700
4701<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>
4702
4703<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4704
4705<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>
4706
4707<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>
4708
4709<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>
4710
4711<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>
4712
4713<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>
4714
4715<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>
4716
4717<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>
4718
4719<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>
4720
4721<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4722
4723<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>
4724
4725<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>
4726
4727<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4728
4729<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4730
4731<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4732
4733<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>
4734
4735<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4736
4737<p>60. Android Application Development-Related Settings:</p>
4738
4739<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>
4740
4741<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>
4742
4743<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>
4744
4745<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4746
4747<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>
4748
4749<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>
4750
4751<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4752
4753<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>
4754
4755<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>
4756
4757<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>
4758
4759<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>
4760
4761<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>
4762
4763<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>
4764
4765<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>
4766
4767<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4768
4769<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>
4770
4771<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>
4772
4773<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>
4774
4775<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>
4776
4777<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>
4778
4779<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>
4780
4781<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>
4782
4783<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>
4784
4785<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>
4786
4787<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>
4788
4789<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>
4790
4791<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>
4792
4793<p>86. Android NFC Sharing Settings:</p>
4794
4795<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>
4796
4797<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>
4798
4799<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>
4800
4801<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>
4802
4803<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>
4804
4805<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>
4806
4807<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>
4808
4809<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>
4810
4811<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>
4812
4813<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>
4814
4815<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4816
4817<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>
4818
4819<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>
4820
4821<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>
4822
4823<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>
4824
4825<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>
4826
4827<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>
4828
4829<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>
4830
4831<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4832
4833<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>
4834
4835<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4836
4837<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>
4838
4839<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4840
4841<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>
4842
4843<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4844
4845<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>
4846
4847<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>
4848
4849<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>
4850
4851<p>Many of these resources are derived directly or indirectly from the Android
4852SDK, and will be functionally identical to the information in that SDK&rsquo;s
4853documentation. In any cases where this Compatibility Definition or the
4854Compatibility Test Suite disagrees with the SDK documentation, the SDK
4855documentation is considered authoritative. Any technical details provided in
4856the references included above are considered by inclusion to be part of this
4857Compatibility Definition.</p>
4858
4859</div>
4860</body>
4861</html>