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2<head>
3<title>Android ANDROID_VERSION Compatibility Definition</title>
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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
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]145<p class="toc_h1"><a href="#6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</a></p>
146
147<p class="toc_h2"><a href="#6_1_developer_tools">6.1. Developer Tools</a></p>
148
149<p class="toc_h2"><a href="#6_2_developer_options">6.2. Developer Options</a></p>
150
151<p class="toc_h1"><a href="#7_hardware_compatibility">7. Hardware Compatibility</a></p>
152
153<p class="toc_h2"><a href="#7_1_display_and_graphics">7.1. Display and Graphics</a></p>
154
155<p class="toc_h3"><a href="#7_1_1_screen_configuration">7.1.1. Screen Configuration</a></p>
156
157<p class="toc_h4"><a href="#7_1_1_1_screen_size">7.1.1.1. Screen Size</a></p>
158
159<p class="toc_h4"><a href="#7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</a></p>
160
161<p class="toc_h4"><a href="#7_1_1_3_screen_density">7.1.1.3. Screen Density</a></p>
162
163
164</div>
165
166<div style="clear: both; page-break-after:always; height:1px"></div>
167
168
169<div id="toc_left_2">
170
171<p class="toc_h3"><a href="#7_1_2_display_metrics">7.1.2. Display Metrics</a></p>
172
173<p class="toc_h3"><a href="#7_1_3_screen_orientation">7.1.3. Screen Orientation</a></p>
174
175<p class="toc_h3"><a href="#7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</a></p>
176
177<p class="toc_h3"><a href="#7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</a></p>
178
179<p class="toc_h3"><a href="#7_1_6_screen_technology">7.1.6. Screen Technology</a></p>
180
181<p class="toc_h3"><a href="#7_1_7_external_displays">7.1.7. Secondary Displays</a></p>
182
183<p class="toc_h2"><a href="#7_2_input_devices">7.2. Input Devices</a></p>
184
185<p class="toc_h3"><a href="#7_2_1_keyboard">7.2.1. Keyboard</a></p>
186
187<p class="toc_h3"><a href="#7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</a></p>
188
189<p class="toc_h3"><a href="#7_2_3_navigation_keys">7.2.3. Navigation Keys</a></p>
190
191<p class="toc_h3"><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen Input</a></p>
192
193<p class="toc_h3"><a href="#7_2_5_fake_touch_input">7.2.5. Fake Touch Input</a></p>
194
195<p class="toc_h3"><a href="#7_2_6_game_controller_support">7.2.6. Game Controller Support</a></p>
196
197<p class="toc_h4"><a href="#7_2_6_1_button_mapping">7.2.6.1. Button Mappings</a></p>
198
199<p class="toc_h3"><a href="#7_2_7_remote_control">7.2.7. Remote Control</a></p>
200
201<p class="toc_h2"><a href="#7_3_sensors">7.3. Sensors</a></p>
202
203<p class="toc_h3"><a href="#7_3_1_accelerometer">7.3.1. Accelerometer</a></p>
204
205<p class="toc_h3"><a href="#7_3_2_magnetometer">7.3.2. Magnetometer</a></p>
206
207<p class="toc_h3"><a href="#7_3_3_gps">7.3.3. GPS</a></p>
208
209<p class="toc_h3"><a href="#7_3_4_gyroscope">7.3.4. Gyroscope</a></p>
210
211<p class="toc_h3"><a href="#7_3_5_barometer">7.3.5. Barometer</a></p>
212
213<p class="toc_h3"><a href="#7_3_6_thermometer">7.3.6. Thermometer</a></p>
214
215<p class="toc_h3"><a href="#7_3_7_photometer">7.3.7. Photometer</a></p>
216
217<p class="toc_h3"><a href="#7_3_8_proximity_sensor">7.3.8. Proximity Sensor</a></p>
218
219<p class="toc_h2"><a href="#7_4_data_connectivity">7.4. Data Connectivity</a></p>
220
221<p class="toc_h3"><a href="#7_4_1_telephony">7.4.1. Telephony</a></p>
222
223<p class="toc_h3"><a href="#7_4_2_ieee_80211_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
224
225<p class="toc_h4"><a href="#7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</a></p>
226
227<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>
228
229<p class="toc_h3"><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></p>
230
231<p class="toc_h3"><a href="#7_4_4_near-field_communications">7.4.4. Near-Field Communications</a></p>
232
233<p class="toc_h3"><a href="#7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</a></p>
234
235<p class="toc_h3"><a href="#7_4_6_sync_settings">7.4.6. Sync Settings</a></p>
236
237<p class="toc_h2"><a href="#7_5_cameras">7.5. Cameras</a></p>
238
239<p class="toc_h3"><a href="#7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</a></p>
240
241<p class="toc_h3"><a href="#7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</a></p>
242
243<p class="toc_h3"><a href="#7_5_3_external_camera">7.5.3. External Camera</a></p>
244
245<p class="toc_h3"><a href="#7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</a></p>
246
247
248
249
250
251</div>
252
253<div id="toc_right_2">
254
255<p class="toc_h3"><a href="#7_5_5_camera_orientation">7.5.5. Camera Orientation</a></p>
256
257<p class="toc_h2"><a href="#7_6_memory_and_storage">7.6. Memory and Storage</a></p>
258
259<p class="toc_h3"><a href="#7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</a></p>
260
261<p class="toc_h3"><a href="#7_6_2_application_shared_storage">7.6.2. Application Shared Storage</a></p>
262
263<p class="toc_h2"><a href="#7_7_usb">7.7. USB</a></p>
264
265<p class="toc_h2"><a href="#7_8_audio">7.8. Audio</a></p>
266
267<p class="toc_h3"><a href="#7_8_1_microphone">7.8.1. Microphone</a></p>
268
269<p class="toc_h3"><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></p>
270
271<p class="toc_h4"><a href="#7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</a></p>
272
273<p class="toc_h1"><a href="#8_performance_compatibility">8. Performance Compatibility</a></p>
274
275<p class="toc_h2"><a href="#8_1_user_experience_consistency">8.1. User Experience Consistency</a></p>
276
277<p class="toc_h2"><a href="#8_2_memory_performance">8.2. Memory Performance</a></p>
278
279<p class="toc_h1"><a href="#9_security_model_compatibility">9. Security Model Compatibility</a></p>
280
281<p class="toc_h2"><a href="#9_1_permissions">9.1. Permissions</a></p>
282
283<p class="toc_h2"><a href="#9_2_uid_and_process_isolation">9.2. UID and Process Isolation</a></p>
284
285<p class="toc_h2"><a href="#9_3_filesystem_permissions">9.3. Filesystem Permissions</a></p>
286
287<p class="toc_h2"><a href="#9_4_alternate_execution_environments">9.4. Alternate Execution Environments</a></p>
288
289<p class="toc_h2"><a href="#9_5_multi-user_support">9.5. Multi-User Support</a></p>
290
291<p class="toc_h2"><a href="#9_6_premium_sms_warning">9.6. Premium SMS Warning</a></p>
292
293<p class="toc_h2"><a href="#9_7_kernel_security_features">9.7. Kernel Security Features</a></p>
294
295<p class="toc_h2"><a href="#9_8_privacy">9.8. Privacy</a></p>
296
297<p class="toc_h2"><a href="#9_9_full-disk-encryption">9.9. Full-Disk Encryption</a></p>
298
299<p class="toc_h2"><a href="#9_10_verified_boot">9.10. Verified Boot</a></p>
300
301<p class="toc_h1"><a href="#10_software_compatibility_testing">10. Software Compatibility Testing</a></p>
302
303<p class="toc_h2"><a href="#10_1_compatibility_test_suite">10.1. Compatibility Test Suite</a></p>
304
305<p class="toc_h2"><a href="#10_2_cts_verifier">10.2. CTS Verifier</a></p>
306
307<p class="toc_h1"><a href="#11_updatable_software">11. Updatable Software</a></p>
308
309<p class="toc_h1"><a href="#12_document_changelog">12. Document Changelog</a></p>
310
311<p class="toc_h1"><a href="#13_contact_us">13. Contact Us</a></p>
312
313<p class="toc_h1"><a href="#14_resources">14. Resources</a></p>
314
315</div>
316
317</div>
318
319<div style="clear: both"></div>
320
321<div id="main">
322
323<h1 id="1_introduction">1. Introduction</h1>
324
325
326<p>This document enumerates the requirements that must be met in order for devices
327to be compatible with Android ANDROID_VERSION.</p>
328
329<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
330defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
331
332<p>As used in this document, a &ldquo;device implementer&rdquo; or &ldquo;implementer&rdquo; is a person
333or organization developing a hardware/software solution running Android ANDROID_VERSION. A
334&ldquo;device implementation&rdquo; or &ldquo;implementation is the hardware/software solution
335so developed.</p>
336
337<p>To be considered compatible with Android ANDROID_VERSION, device implementations MUST meet
338the requirements presented in this Compatibility Definition, including any
339documents incorporated via reference.</p>
340
341<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
342implementer to ensure compatibility with existing implementations.</p>
343
344<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
345implementers are strongly encouraged to base their implementations to the
346greatest extent possible on the &ldquo;upstream&rdquo; source code available from the
347Android Open Source Project. While some components can hypothetically be
348replaced with alternate implementations this practice is strongly discouraged,
349as passing the software tests will become substantially more difficult. It is
350the implementer&rsquo;s responsibility to ensure full behavioral compatibility with
351the standard Android implementation, including and beyond the Compatibility
352Test Suite. Finally, note that certain component substitutions and
353modifications are explicitly forbidden by this document.</p>
354
355<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
356functionally identical to the information in that SDK&rsquo;s documentation. For any
357case where this Compatibility Definition or the Compatibility Test Suite
358disagrees with the SDK documentation, the SDK documentation is considered
359authoritative. 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>
360
361<h1 id="2_device_types">2. Device Types</h1>
362
363
364<p>While the Android Open Source Project has been used in the implementation of a
365variety of device types and form factors, many aspects of the architecture and
366compatibility requirements were optimized for handheld devices. Starting from
367Android 5.0, the Android Open Source Project aims to embrace a wider variety of
368device types as described in this section.</p>
369
370<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
371it in the hand, such as mp3 players, phones, and tablets. Android Handheld
372device implementations:</p>
373
374<ul>
375 <li>MUST have a touchscreen embedded in the device.</li>
376 <li>MUST have a power source that provides mobility, such as a battery.</li>
377</ul>
378
379<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
380for consuming digital media, movies, games, apps, and/or live TV for users
381sitting about ten feet away (a &ldquo;lean back&rdquo; or &ldquo;10-foot user interface&rdquo;).
382Android Television devices:</p>
383
384<ul>
385 <li>MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
386or a wireless port for display.</li>
387 <li>MUST declare the features android.software.leanback and
388android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>].</li>
389</ul>
390
391<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
392perhaps on the wrist, and:</p>
393
394<ul>
395 <li>MUST have a screen with the physical diagonal length in the range from 1.1 to
3962.5 inches.</li>
397 <li>MUST declare the feature android.hardware.type.watch.</li>
398 <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>
399</ul>
400
401<p><strong>Android Automotive implementation</strong> refers to a vehicle head
402unit running Android as an operating system for part or all of the system and/or
403infotainment functionality. Android Automotive implementations MUST support
404uiMode = UI_MODE_TYPE_CAR [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">Resources, 111</a>].</p>
405
406<p>All Android device implementations that do not fit into any of the above device
407types still MUST meet all requirements in this document to be Android ANDROID_VERSION
408compatible, unless the requirement is explicitly described to be only
409applicable to a specific Android device type from above.</p>
410
411<h2 id="2_1_device_configurations">2.1 Device Configurations</h2>
412
413
414<p>This is a summary of major differences in hardware configuration by device
415type. (Empty cells denote a &ldquo;MAY&rdquo;). Not all configurations are covered in this
416table; see relevant hardware sections for more detail.</p>
417<table>
418 <tr>
419 <th>Category</th>
420 <th>Feature</th>
421 <th>Section</th>
422 <th>Handheld</th>
423 <th>Television</th>
424 <th>Watch</th>
425 <th>Automotive</th>
426 <th>Other</th>
427 </tr>
428 <tr>
429 <td rowspan="3">Input</td>
430 <td>D-pad</td>
431 <td><a href="#7_2_2_non-touch-navigation">7.2.2. Non-touch Navigation</a></td>
432 <td></td>
433 <td>MUST</td>
434 <td></td>
435 <td></td>
436 <td></td>
437 </tr>
438 <tr>
439 <td>Touchscreen </td>
440 <td><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen input</a></td>
441 <td>MUST</td>
442 <td></td>
443 <td>MUST</td>
444 <td></td>
445 <td>SHOULD</td>
446 </tr>
447 <tr>
448 <td>Microphone </td>
449 <td><a href="#7_8_1_microphone">7.8.1. Microphone</a></td>
450 <td>MUST</td>
451 <td>SHOULD </td>
452 <td>MUST</td>
453 <td>MUST</td>
454 <td>SHOULD</td>
455 </tr>
456 <tr>
457 <td rowspan="2">Sensors</td>
458 <td>Accelerometer </td>
459 <td><a href="#7_3_1_accelerometer">7.3.1 Accelerometer</a></td>
460 <td>SHOULD</td>
461 <td></td>
462 <td>SHOULD</td>
463 <td></td>
464 <td>SHOULD</td>
465 </tr>
466 <tr>
467 <td>GPS</td>
468 <td><a href="#7_3_3_gps">7.3.3. GPS</a></td>
469 <td>SHOULD</td>
470 <td></td>
471 <td></td>
472 <td>SHOULD</td>
473 <td></td>
474 </tr>
475 <tr>
476 <td rowspan="5">Connectivity</td>
477 <td>Wi-Fi</td>
478 <td><a href="#7_4_2_ieee_802.11">7.4.2. IEEE 802.11</a></td>
479 <td>SHOULD</td>
480 <td> MUST</td>
481 <td></td>
482 <td>SHOULD</td>
483 <td>SHOULD</td>
484 </tr>
485 <tr>
486 <td>Wi-Fi Direct</td>
487 <td><a href="#7_4_2_1_wi-fi-direct">7.4.2.1. Wi-Fi Direct</a></td>
488 <td>SHOULD</td>
489 <td>SHOULD</td>
490 <td></td>
491 <td></td>
492 <td>SHOULD</td>
493 </tr>
494 <tr>
495 <td>Bluetooth</td>
496 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
497 <td>SHOULD</td>
498 <td>MUST</td>
499 <td>MUST</td>
500 <td>MUST</td>
501 <td>SHOULD</td>
502 </tr>
503 <tr>
504 <td>Bluetooth Low Energy</td>
505 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
506 <td>SHOULD</td>
507 <td>MUST</td>
508 <td>SHOULD</td>
509 <td>SHOULD</td>
510 <td>SHOULD</td>
511 </tr>
512 <tr>
513 <td>USB peripheral/host mode</td>
514 <td><a href="#7_7_usb">7.7. USB</a></td>
515 <td>SHOULD</td>
516 <td></td>
517 <td></td>
518 <td>SHOULD</td>
519 <td>SHOULD</td>
520 </tr>
521 <tr>
522 <td>Output</td>
523 <td>Speaker and/or Audio output ports</td>
524 <td><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></td>
525 <td>MUST</td>
526 <td>MUST</td>
527 <td></td>
528 <td>MUST</td>
529 <td>MUST</td>
530 </tr>
531</table>
532
533
534<h1 id="3_software">3. Software</h1>
535
536
537<h2 id="3_1_managed_api_compatibility">3.1. Managed API Compatibility</h2>
538
539
540<p>The managed Dalvik bytecode execution environment is the primary vehicle for
541Android applications. The Android application programming interface (API) is
542the set of Android platform interfaces exposed to applications running in the
543managed runtime environment. Device implementations MUST provide complete
544implementations, including all documented behaviors, of any documented API
545exposed 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
546source code. </p>
547
548<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
549signatures, deviate from the documented behavior, or include no-ops, except
550where specifically allowed by this Compatibility Definition.</p>
551
552<p>This Compatibility Definition permits some types of hardware for which Android
553includes APIs to be omitted by device implementations. In such cases, the APIs
554MUST 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>
555
556<h2 id="3_2_soft_api_compatibility">3.2. Soft API Compatibility</h2>
557
558
559<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
560such things as intents, permissions, and similar aspects of Android
561applications that cannot be enforced at application compile time.</p>
562
563<h3 id="3_2_1_permissions">3.2.1. Permissions</h3>
564
565
566<p>Device implementers MUST support and enforce all permission constants as
567documented 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>
568
569<h3 id="3_2_2_build_parameters">3.2.2. Build Parameters</h3>
570
571
572<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,
573meaningful values across device implementations, the table below includes
574additional restrictions on the formats of these values to which device
575implementations MUST conform.</p>
576<table>
577 <tr>
578 <th>Parameter</th>
579 <th>Details</th>
580 </tr>
581 <tr>
582 <td>VERSION.RELEASE</td>
583 <td>The version of the currently-executing Android system, in human-readable
584format. 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>
585 </tr>
586 <tr>
587 <td>VERSION.SDK</td>
588 <td>The version of the currently-executing Android system, in a format accessible
589to third-party application code. For Android ANDROID_VERSION, this field MUST have the
590integer value 22.</td>
591 </tr>
592 <tr>
593 <td>VERSION.SDK_INT</td>
594 <td>The version of the currently-executing Android system, in a format accessible
595to third-party application code. For Android ANDROID_VERSION, this field MUST have the
596integer value 22.</td>
597 </tr>
598 <tr>
599 <td>VERSION.INCREMENTAL</td>
600 <td>A value chosen by the device implementer designating the specific build of the
601currently-executing Android system, in human-readable format. This value MUST
602NOT be reused for different builds made available to end users. A typical use
603of this field is to indicate which build number or source-control change
604identifier was used to generate the build. There are no requirements on the
605specific format of this field, except that it MUST NOT be null or the empty
606string ("").</td>
607 </tr>
608 <tr>
609 <td>BOARD</td>
610 <td>A value chosen by the device implementer identifying the specific internal
611hardware used by the device, in human-readable format. A possible use of this
612field is to indicate the specific revision of the board powering the device.
613The value of this field MUST be encodable as 7-bit ASCII and match the regular
614expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
615 </tr>
616 <tr>
617 <td>BRAND</td>
618 <td>A value reflecting the brand name associated with the device as known to the
619end users. MUST be in human-readable format and SHOULD represent the
620manufacturer of the device or the company brand under which the device is
621marketed. The value of this field MUST be encodable as 7-bit ASCII and match
622the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
623 </tr>
624 <tr>
625 <td>SUPPORTED_ABIS</td>
626 <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>
627 </tr>
628 <tr>
629 <td>SUPPORTED_32_BIT_ABIS</td>
630 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
631 </tr>
632 <tr>
633 <td>SUPPORTED_64_BIT_ABIS</td>
634 <td>The name of the second instruction set (CPU type + ABI convention) of native
635code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
636 </tr>
637 <tr>
638 <td>CPU_ABI</td>
639 <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>
640 </tr>
641 <tr>
642 <td>CPU_ABI2</td>
643 <td>The name of the second instruction set (CPU type + ABI convention) of native
644code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
645 </tr>
646 <tr>
647 <td>DEVICE</td>
648 <td>A value chosen by the device implementer containing the development name or
649code name identifying the configuration of the hardware features and industrial
650design of the device. The value of this field MUST be encodable as 7-bit ASCII
651and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
652 </tr>
653 <tr>
654 <td>FINGERPRINT</td>
655 <td>A string that uniquely identifies this build. It SHOULD be reasonably
656human-readable. It MUST follow this template:</p>
657
658<p class="small">$(BRAND)/$(PRODUCT)/$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
659
660<p>For example: acme/myproduct/mydevice:ANDROID_VERSION/LMYXX/3359:userdebug/test-keys</p>
661
662<p>The fingerprint MUST NOT include whitespace characters. If other fields
663included in the template above have whitespace characters, they MUST be
664replaced in the build fingerprint with another character, such as the
665underscore ("_") character. The value of this field MUST be encodable as 7-bit
666ASCII.</td>
667 </tr>
668 <tr>
669 <td>HARDWARE</td>
670 <td>The name of the hardware (from the kernel command line or /proc). It SHOULD be
671reasonably human-readable. The value of this field MUST be encodable as 7-bit
672ASCII and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;. </td>
673 </tr>
674 <tr>
675 <td>HOST</td>
676 <td>A string that uniquely identifies the host the build was built on, in
677human-readable format. There are no requirements on the specific format of this
678field, except that it MUST NOT be null or the empty string ("").</td>
679 </tr>
680 <tr>
681 <td>ID</td>
682 <td>An identifier chosen by the device implementer to refer to a specific release,
683in human-readable format. This field can be the same as
684android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
685meaningful for end users to distinguish between software builds. The value of
686this field MUST be encodable as 7-bit ASCII and match the regular expression &ldquo;^[a-zA-Z0-9._-]+$&rdquo;.</td>
687 </tr>
688 <tr>
689 <td>MANUFACTURER</td>
690 <td>The trade name of the Original Equipment Manufacturer (OEM) of the product.
691There are no requirements on the specific format of this field, except that it
692MUST NOT be null or the empty string ("").</td>
693 </tr>
694 <tr>
695 <td>MODEL</td>
696 <td>A value chosen by the device implementer containing the name of the device as
697known to the end user. This SHOULD be the same name under which the device is
698marketed and sold to end users. There are no requirements on the specific
699format of this field, except that it MUST NOT be null or the empty string ("").</td>
700 </tr>
701 <tr>
702 <td>PRODUCT</td>
703 <td>A value chosen by the device implementer containing the development name or
704code name of the specific product (SKU) that MUST be unique within the same
705brand. MUST be human-readable, but is not necessarily intended for view by end
706users. The value of this field MUST be encodable as 7-bit ASCII and match the
707regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
708 </tr>
709 <tr>
710 <td>SERIAL</td>
711 <td>A hardware serial number, which MUST be available. The value of this field MUST
712be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
713 </tr>
714 <tr>
715 <td>TAGS</td>
716 <td>A comma-separated list of tags chosen by the device implementer that further
717distinguishes the build. This field MUST have one of the values corresponding
718to the three typical Android platform signing configurations: release-keys,
719dev-keys, test-keys. </td>
720 </tr>
721 <tr>
722 <td>TIME</td>
723 <td>A value representing the timestamp of when the build occurred.</td>
724 </tr>
725 <tr>
726 <td>TYPE</td>
727 <td>A value chosen by the device implementer specifying the runtime configuration
728of the build. This field MUST have one of the values corresponding to the three
729typical Android runtime configurations: user, userdebug, or eng.</td>
730 </tr>
731 <tr>
732 <td>USER</td>
733 <td>A name or user ID of the user (or automated user) that generated the build.
734There are no requirements on the specific format of this field, except that it
735MUST NOT be null or the empty string ("").</td>
736 </tr>
737</table>
738
739
740<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
741
742
743<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
744described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
745implementer MUST provide an Android Activity or Service that specifies a
746matching intent filter that binds to and implements correct behavior for each
747specified intent pattern.</p>
748
749<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
750
751
752<p>Android intents allow application components to request functionality from
753other Android components. The Android upstream project includes a list of
754applications considered core Android applications, which implements several
755intent patterns to perform common actions. The core Android applications are:</p>
756
757<ul>
758 <li>Desk Clock</li>
759 <li>Browser</li>
760 <li>Calendar</li>
761 <li>Contacts</li>
762 <li>Gallery</li>
763 <li>GlobalSearch</li>
764 <li>Launcher</li>
765 <li>Music</li>
766 <li>Settings</li>
767</ul>
768
769<p>Device implementations SHOULD include the core Android applications as
770appropriate but MUST include a component implementing the same intent patterns
771defined by all the &ldquo;public&rdquo; Activity or Service components of these core
772Android applications. Note that Activity or Service components are considered
773&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
774
775<h4 id="3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</h4>
776
777
778<p>As Android is an extensible platform, device implementations MUST allow each
779intent 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
780implementation allows this by default; device implementers MUST NOT attach
781special privileges to system applications' use of these intent patterns, or
782prevent third-party applications from binding to and assuming control of these
783patterns. This prohibition specifically includes but is not limited to
784disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
785multiple applications that all handle the same intent pattern.</p>
786
787<p>However, device implementations MAY provide default activities for specific URI
788patterns (eg. http://play.google.com) if the default activity provides a more
789specific filter for the data URI. For example, an intent filter specifying the
790data 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
791modify the default activity for intents.</p>
792
793<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
794
795
796<p>Device implementations MUST NOT include any Android component that honors any
797new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
798string in the android.* or com.android.* namespace. Device implementers MUST
799NOT include any Android components that honor any new intent or broadcast
800intent patterns using an ACTION, CATEGORY, or other key string in a package
801space belonging to another organization. Device implementers MUST NOT alter or
802extend 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
803and obviously associated with their own organization. This prohibition is
804analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
805
806<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
807
808
809<p>Third-party applications rely on the platform to broadcast certain intents to
810notify them of changes in the hardware or software environment.
811Android-compatible devices MUST broadcast the public broadcast intents in
812response to appropriate system events. Broadcast intents are described in the
813SDK documentation.</p>
814
815<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
816
817
818<p>Android includes settings that provide users an easy way to select their
819default applications, for example for Home screen or SMS. Where it makes sense,
820device implementations MUST provide a similar settings menu and be compatible
821with the intent filter pattern and API methods described in the SDK
822documentation as below.</p>
823
824<p>Device implementations:</p>
825
826<ul>
827 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
828settings menu for Home Screen, if the device implementation reports
829android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
830 <li>MUST provide a settings menu that will call the
831android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
832change the default SMS application, if the device implementation reports
833android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]</li>
834 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
835app settings menu for Tap and Pay, if the device implementation reports
836android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
837</ul>
838
839<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
840
841
842<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
843
844
845<p>Managed Dalvik bytecode can call into native code provided in the application
846.apk file as an ELF .so file compiled for the appropriate device hardware
847architecture. As native code is highly dependent on the underlying processor
848technology, Android defines a number of Application Binary Interfaces (ABIs) in
849the Android NDK. Device implementations MUST be compatible with one or more
850defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
851
852<p>If a device implementation includes support for an Android ABI, it:</p>
853
854<ul>
855 <li>MUST include support for code running in the managed environment to call into
856native code, using the standard Java Native Interface (JNI) semantics</li>
857 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
858the ABI) with each required library in the list below</li>
859 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
860 <li>MUST accurately report the native Application Binary Interface (ABI) supported
861by the device, via the android.os.Build.SUPPORTED_ABIS,
862android.os.Build.SUPPORTED_32_BIT_ABIS, and
863android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
864of ABIs ordered from the most to the least preferred one</li>
865 <li>MUST report, via the above parameters, only those ABIs documented in the latest
866version of the Android NDK, &ldquo;NDK Programmer&rsquo;s Guide | ABI Management&rdquo; in docs/
867directory</li>
868 <li>SHOULD be built using the source code and header files available in the
869upstream Android Open Source Project</li>
870</ul>
871
872<p>The following native code APIs MUST be available to apps that include native
873code:</p>
874
875<ul>
876 <li>libc (C library)</li>
877 <li>libm (math library)</li>
878 <li>Minimal support for C++</li>
879 <li>JNI interface</li>
880 <li>liblog (Android logging)</li>
881 <li>libz (Zlib compression)</li>
882 <li>libdl (dynamic linker)</li>
883 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
884 <li>libGLESv2.so (OpenGL ES 2.0)</li>
885 <li>libGLESv3.so (OpenGL ES 3.x)</li>
886 <li>libEGL.so (native OpenGL surface management)</li>
887 <li>libjnigraphics.so</li>
888 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
889 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
890 <li>libandroid.so (native Android activity support)</li>
891 <li>libmediandk.so (native media APIs support)</li>
892 <li>Support for OpenGL, as described below</li>
893</ul>
894
895<p>Note that future releases of the Android NDK may introduce support for
896additional ABIs. If a device implementation is not compatible with an existing
897predefined ABI, it MUST NOT report support for any ABIs at all.</p>
898
899<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
900(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
901Android 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
902symbols must be present, only the corresponding functions for OpenGL ES
903versions and extensions actually supported by the device must be fully
904implemented.</p>
905
906<p>Native code compatibility is challenging. For this reason, device implementers
907are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
908Android Open Source Project. </p>
909
910<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9113.3.2. 32-bit ARM Native Code Compatibility
912</h3>
913
914<p>The ARMv8 architecture deprecates several CPU operations, including some
915operations used in existing native code. On 64-bit ARM devices, the following
916deprecated operations MUST remain available to 32-bit native ARM code, either
917through native CPU support or through software emulation:</p>
918
919<ul>
920<li>SWP and SWPB instructions</li>
921<li>SETEND instruction</li>
922<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
923</ul>
924
925<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
926from 32-bit ARM native code. For compatibility with applications built using this
927NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
928by 32-bit ARM applications:</p>
929
930<ul>
931<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
932supported by the device</li>
933<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
934highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
935</ul>
936
937<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
938applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
939non-ARM applications.</p>
940
941<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
942
943
944<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
945
946<div class="note">
947<p>Android Watch devices MAY, but all other device implementations MUST provide
948a complete implementation of the android.webkit.Webview API.</p>
949</div>
950
951
952<p>The platform feature android.software.webview MUST be reported on any device
953that provides a complete implementation of the android.webkit.WebView API, and
954MUST NOT be reported on devices without a complete implementation of the API.
955The Android Open Source implementation uses code from the Chromium Project to
956implement 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
957rendering system, device implementers MUST use the specific upstream build of
958Chromium in the WebView implementation. Specifically:</p>
959
960<ul>
961 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
962build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
963includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
964 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]965<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]966AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
967Safari/537.36</p>
968 <ul>
969 <li>The value of the $(VERSION) string MUST be the same as the value for
970android.os.Build.VERSION.RELEASE.</li>
971 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
972 note that this is a webview</li>
973 <li>The value of the $(MODEL) string MUST be the same as the value for
974android.os.Build.MODEL.</li>
975 <li>The value of the $(BUILD) string MUST be the same as the value for
976android.os.Build.ID.</li>
977 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
978upstream Android Open Source Project.</li>
979 <li>Device implementations MAY omit Mobile in the user agent string.</li>
980 </ul></li></ul>
981
982<p>The WebView component SHOULD include support for as many HTML5 features as
983possible and if it supports the feature SHOULD conform to the HTML5
984specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
985
986<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
987
988<div class="note">
989<p>Android Television, Watch, and Android Automotive implementations MAY omit a
990browser application, but MUST support the public intent patterns as described in
991<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
992of device implementations MUST include a standalone Browser application for
993general user web browsing.</p>
994</div>
995
996<p>The standalone Browser MAY be based on a browser technology other than WebKit.
997However, even if an alternate Browser application is used, the
998android.webkit.WebView component provided to third-party applications MUST be
999based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1000
1001<p>Implementations MAY ship a custom user agent string in the standalone Browser
1002application.</p>
1003
1004<p>The standalone Browser application (whether based on the upstream WebKit
1005Browser application or a third-party replacement) SHOULD include support for as
1006much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1007APIs associated with HTML5:</p>
1008
1009<ul>
1010 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1011 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1012 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1013</ul>
1014
1015<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1016[<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
1017IndexedDB over webstorage, IndexedDB is expected to become a required component
1018in a future version of Android.</p>
1019
1020<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1021
1022
1023<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1024consistent with the preferred implementation of the upstream Android Open
1025Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1026
1027<ul>
1028 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1029 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1030type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1031 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1032</ul>
1033
1034<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1035significant portions of the platform for behavioral compatibility, but not all.
1036It is the responsibility of the implementer to ensure behavioral compatibility
1037with the Android Open Source Project. For this reason, device implementers
1038SHOULD use the source code available via the Android Open Source Project where
1039possible, rather than re-implement significant parts of the system.</p>
1040
1041<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1042
1043
1044<p>Android follows the package and class namespace conventions defined by the Java
1045programming language. To ensure compatibility with third-party applications,
1046device implementers MUST NOT make any prohibited modifications (see below) to
1047these package namespaces:</p>
1048
1049<ul>
1050 <li>java.*</li>
1051 <li>javax.*</li>
1052 <li>sun.*</li>
1053 <li>android.*</li>
1054 <li>com.android.*</li>
1055</ul>
1056
1057<p><strong>Prohibited modifications include</strong>:</p>
1058
1059<ul>
1060 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1061platform by changing any method or class signatures, or by removing classes or
1062class fields.</li>
1063 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1064such modifications MUST NOT impact the stated behavior and Java-language
1065signature of any publicly exposed APIs.</li>
1066 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1067or interfaces, or fields or methods to existing classes or interfaces) to the
1068APIs above.</li>
1069</ul>
1070
1071<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,
1072device implementers MUST NOT expose new APIs or alter existing APIs in the
1073namespaces noted above. Device implementers MAY make internal-only
1074modifications, but those modifications MUST NOT be advertised or otherwise
1075exposed to developers.</p>
1076
1077<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1078namespace owned by or referring to another organization. For instance, device
1079implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1080Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1081namespaces. Additionally, if a device implementation includes custom APIs
1082outside the standard Android namespace, those APIs MUST be packaged in an
1083Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1084lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1085APIs.</p>
1086
1087<p>If a device implementer proposes to improve one of the package namespaces above
1088(such as by adding useful new functionality to an existing API, or adding a new
1089API), 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
1090information on that site.</p>
1091
1092<p>Note that the restrictions above correspond to standard conventions for naming
1093APIs in the Java programming language; this section simply aims to reinforce
1094those conventions and make them binding through inclusion in this Compatibility
1095Definition.</p>
1096
1097<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1098
1099
1100<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1101Dalvik 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
1102the Dalvik Executable Format, and the reference implementation&rsquo;s package
1103management system.</p>
1104
1105<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1106accordance with the upstream Android platform, and as specified by the
1107following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1108
1109<p>Note that memory values specified below are considered minimum values and
1110device implementations MAY allocate more memory per application.</p>
1111
1112<table>
1113 <tr>
1114 <th>Screen Layout</th>
1115 <th>Screen Density</th>
1116 <th>Minimum Application Memory</th>
1117 </tr>
1118 <tr>
1119 <td rowspan="10">small/normal</td>
1120 <td>120 dpi (ldpi)</td>
1121 <td rowspan="2">32MB</td>
1122 </tr>
1123 <tr>
1124 <td>160 dpi (mdpi)</td>
1125 </tr>
1126 <tr>
1127 <td>213 dpi (tvdpi)</td>
1128 <td rowspan="3">48MB</td>
1129 </tr>
1130 <tr>
1131 <td>240 dpi (hdpi)</td>
1132 </tr>
1133 <tr>
1134 <td>280 dpi (280dpi)</td>
1135 </tr>
1136 <tr>
1137 <td>320 dpi (xhdpi)</td>
1138 <td>80MB</td>
1139 </tr>
1140 <tr>
1141 <td>400 dpi (400dpi)</td>
1142 <td>96MB</td>
1143 </tr>
1144 <tr>
1145 <td>480 dpi (xxhdpi)</td>
1146 <td>128MB</td>
1147 </tr>
1148 <tr>
1149 <td>560 dpi (560dpi)</td>
1150 <td>192MB</td>
1151 </tr>
1152 <tr>
1153 <td>640 dpi (xxxhdpi)</td>
1154 <td>256MB</td>
1155 </tr>
1156 <tr>
1157 <td rowspan="10">large</td>
1158 <td>120 dpi (ldpi)</td>
1159 <td>32MB</td>
1160 </tr>
1161 <tr>
1162 <td>160 dpi (mdpi)</td>
1163 <td>48MB</td>
1164 </tr>
1165 <tr>
1166 <td>213 dpi (tvdpi)</td>
1167 <td rowspan="2">80MB</td>
1168 </tr>
1169 <tr>
1170 <td>240 dpi (hdpi)</td>
1171 </tr>
1172 <tr>
1173 <td>280 dpi (280dpi)</td>
1174 <td>96MB</td>
1175 </tr>
1176 <tr>
1177 <td>320 dpi (xhdpi)</td>
1178 <td>128MB</td>
1179 </tr>
1180 <tr>
1181 <td>400 dpi (400dpi)</td>
1182 <td>192MB</td>
1183 </tr>
1184 <tr>
1185 <td>480 dpi (xxhdpi)</td>
1186 <td>256MB</td>
1187 </tr>
1188 <tr>
1189 <td>560 dpi (560dpi)</td>
1190 <td>384MB</td>
1191 </tr>
1192 <tr>
1193 <td>640 dpi (xxxhdpi)</td>
1194 <td>512MB</td>
1195 </tr>
1196 <tr>
1197 <td rowspan="10">xlarge</td>
1198 <td>120 dpi (ldpi)</td>
1199 <td>48MB</td>
1200 </tr>
1201 <tr>
1202 <td>160 dpi (mdpi)</td>
1203 <td>80MB</td>
1204 </tr>
1205 <tr>
1206 <td>213 dpi (tvdpi)</td>
1207 <td rowspan="2">96MB</td>
1208 </tr>
1209 <tr>
1210 <td>240 dpi (hdpi)</td>
1211 </tr>
1212 <tr>
1213 <td>280 dpi (280dpi)</td>
1214 <td>144MB</td>
1215 </tr>
1216 <tr>
1217 <td>320 dpi (xhdpi)</td>
1218 <td>192MB</td>
1219 </tr>
1220 <tr>
1221 <td>400 dpi (400dpi)</td>
1222 <td>288MB</td>
1223 </tr>
1224 <tr>
1225 <td>480 dpi (xxhdpi)</td>
1226 <td>384MB</td>
1227 </tr>
1228 <tr>
1229 <td>560 dpi (560dpi)</td>
1230 <td>576MB</td>
1231 </tr>
1232 <tr>
1233 <td>640 dpi (xxxhdpi)</td>
1234 <td>768MB</td>
1235 </tr>
1236</table>
1237
1238
1239<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1240
1241
1242<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1243
1244
1245<p>Android includes a launcher application (home screen) and support for
1246third-party applications to replace the device launcher (home screen). Device
1247implementations that allow third-party applications to replace the device home
1248screen MUST declare the platform feature android.software.home_screen.</p>
1249
1250<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1251
1252<div class="note">
1253<p>Widgets are optional for all Android device implementations, but SHOULD be
1254supported on Android Handheld devices.</p>
1255</div>
1256
1257
1258<p>Android defines a component type and corresponding API and lifecycle that
1259allows 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
1260implementations. Device implementations that support embedding widgets on the
1261home screen MUST meet the following requirements and declare support for
1262platform feature android.software.app_widgets.</p>
1263
1264<ul>
1265 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1266interface affordances to add, configure, view, and remove AppWidgets directly
1267within the Launcher.</li>
1268 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1269the standard grid size. See the App Widget Design Guidelines in the Android SDK
1270documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1271 <li>Device implementations that include support for lock screen MAY support
1272application widgets on the lock screen.</li>
1273</ul>
1274
1275<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1276
1277
1278<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>
1279
1280<p>Some APIs allow applications to perform notifications or attract attention
1281using hardware&#8212;specifically sound, vibration, and light. Device implementations
1282MUST support notifications that use hardware features, as described in the SDK
1283documentation, and to the extent possible with the device implementation
1284hardware. For instance, if a device implementation includes a vibrator, it MUST
1285correctly implement the vibration APIs. If a device implementation lacks
1286hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1287is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1288
1289<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1290etc.) provided for in the APIs
1291[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1292or in the Status/System Bar icon style guide
1293[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1294which in the case of an Android Television device includes the possibility to not display the
1295notifications. Device implementers MAY provide an alternative user experience for
1296notifications than that provided by the reference Android Open Source
1297implementation; however, such alternative notification systems MUST support
1298existing notification resources, as above. </p>
1299
1300<p>Android includes support for various notifications, such as:</p>
1301
1302<ul>
1303 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1304 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1305 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1306</ul>
1307
1308<p>Android device implementations, when such notifications are made visible, MUST properly execute
1309Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1310APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1311</p>
1312
1313<p>Android includes Notification Listener Service APIs that allow apps (once
1314explicitly enabled by the user) to receive a copy of all notifications as they
1315are posted or updated. Device implementations MUST correctly and promptly send
1316notifications in their entirety to all such installed and user-enabled listener
1317services, including any and all metadata attached to the Notification object.</p>
1318
1319<h3 id="3_8_4_search">3.8.4. Search</h3>
1320
1321
1322<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
1323expose their application&rsquo;s data into the global system search. Generally
1324speaking, this functionality consists of a single, system-wide user interface
1325that allows users to enter queries, displays suggestions as users type, and
1326displays results. The Android APIs allow developers to reuse this interface to
1327provide search within their own apps, and allow developers to supply results to
1328the common global search user interface.</p>
1329
1330<p>Android device implementations SHOULD include global search, a single, shared,
1331system-wide search user interface capable of real-time suggestions in response
1332to user input. Device implementations SHOULD implement the APIs that allow
1333developers to reuse this user interface to provide search within their own
1334applications. Device implementations that implement the global search interface
1335MUST implement the APIs that allow third-party applications to add suggestions
1336to the search box when it is run in global search mode. If no third-party
1337applications are installed that make use of this functionality, the default
1338behavior SHOULD be to display web search engine results and suggestions.</p>
1339
1340<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1341
1342
1343<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1344end 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
1345some high-visibility manner.</p>
1346
1347<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1348
1349
1350<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1351across an entire Activity or application.</p>
1352
1353<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1354application developers to use if they want to match the Holo theme look and
1355feel 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
1356exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1357
1358<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1359application developers to use if they want to match the design theme&rsquo;s look and
1360feel across the wide variety of different Android device types. Device
1361implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1362of 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>
1363
1364<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1365styles for application developers to use if they want to match the look and
1366feel of the device theme as defined by the device implementer. Device
1367implementations MAY modify the Device Default theme attributes exposed to
1368applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1369
1370<p>Android supports a new variant theme with translucent system bars, which allows
1371application developers to fill the area behind the status and navigation bar
1372with their app content. To enable a consistent developer experience in this
1373configuration, it is important the status bar icon style is maintained across
1374different device implementations. Therefore, Android device implementations
1375MUST use white for system status icons (such as signal strength and battery
1376level) and notifications issued by the system, unless the icon is indicating a
1377problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1378
1379<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1380
1381
1382<p>Android defines a component type and corresponding API and lifecycle that
1383allows 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
1384input capabilities that display as a wallpaper, behind other applications.</p>
1385
1386<p>Hardware is considered capable of reliably running live wallpapers if it can
1387run all live wallpapers, with no limitations on functionality, at a reasonable
1388frame rate with no adverse effects on other applications. If limitations in the
1389hardware cause wallpapers and/or applications to crash, malfunction, consume
1390excessive CPU or battery power, or run at unacceptably low frame rates, the
1391hardware is considered incapable of running live wallpaper. As an example, some
1392live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1393Live wallpaper will not run reliably on hardware that does not support multiple
1394OpenGL contexts because the live wallpaper use of an OpenGL context may
1395conflict with other applications that also use an OpenGL context.</p>
1396
1397<p>Device implementations capable of running live wallpapers reliably as described
1398above SHOULD implement live wallpapers, and when implemented MUST report the
1399platform feature flag android.software.live_wallpaper.</p>
1400
1401<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1402
1403<div class="note">
1404<p>As the Recent function navigation key is OPTIONAL, the requirements to
1405implement the overview screen is OPTIONAL for Android Television devices and
1406Android Watch devices.</p>
1407</div>
1408
1409
1410<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
1411accessed activities and tasks using a thumbnail image of the application&rsquo;s
1412graphical state at the moment the user last left the application. Device
1413implementations 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>
1414
1415<ul>
1416 <li>MUST display affiliated recents as a group that moves together.</li>
1417 <li>MUST support at least up to 20 displayed activities.</li>
1418 <li>MUST at least display the title of 4 activities at a time.</li>
1419 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1420 <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>
1421 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1422interacts with screens.</li>
1423</ul>
1424
1425<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1426interface (or a similar thumbnail-based interface) for the overview screen.</p>
1427
1428<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1429
1430
1431<p>Android includes support for Input Management and support for third-party input
1432method 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
1433the device MUST declare the platform feature android.software.input_methods and
1434support IME APIs as defined in the Android SDK documentation.</p>
1435
1436<p>Device implementations that declare the android.software.input_methods feature
1437MUST provide a user-accessible mechanism to add and configure third-party input
1438methods. Device implementations MUST display the settings interface in response
1439to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1440
1441<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1442
1443
1444<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1445Media Notification Template that allows media applications to integrate with
1446playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1447Device implementations that support a lock screen, unless an Android Automotive or Watch
1448implementation, MUST display the Lockscreen Notifications including the Media Notification
1449Template.</p>
1450
1451<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1452
1453
1454<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
1455a power source is idle or docked in a desk dock. Android Watch devices MAY
1456implement Dreams, but other types of device implementations SHOULD include
1457support for Dreams and provide a settings option for users to configure Dreams
1458in response to the android.settings.DREAM_SETTINGS intent.</p>
1459
1460<h3 id="3_8_12_location">3.8.12. Location</h3>
1461
1462
1463<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1464location coordinates, location modes MUST be displayed in the Location menu
1465within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1466
1467<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1468
1469
1470<p>Android includes support for color emoji characters. When Android device
1471implementations include an IME, devices SHOULD provide an input method to the
1472user 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>
1473
1474<p>Android includes support for Roboto 2 font with different
1475weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1476sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1477the languages available on the device and full Unicode 7.0 coverage of Latin,
1478Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1479all glyphs in the currency symbols block of Unicode 7.0.</p>
1480
1481<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1482
1483
1484<p>Android includes features that allow security-aware applications to perform
1485device administration functions at the system level, such as enforcing password
1486policies or performing remote wipe, through the Android Device Administration
1487API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1488Device implementations MUST provide an implementation of the DevicePolicyManager class
1489[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1490Device implementations that include support for PIN (numeric) or PASSWORD
1491(alphanumeric) based lock screens MUST support the full range of device
1492administration policies defined in the Android SDK documentation
1493[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1494and report the platform feature android.software.device_admin.</p>
1495
1496<p>Device implementations MAY have a preinstalled application performing device
1497administration functions but this application MUST NOT be set out-of-the box as
1498the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1499
1500<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1501
1502
1503<p>Android provides an accessibility layer that helps users with disabilities to
1504navigate their devices more easily. In addition, Android provides platform APIs
1505that enable accessibility service implementations to receive callbacks for user
1506and system events and generate alternate feedback mechanisms, such as
1507text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1508
1509<p>Device implementations include the following requirements:</p>
1510
1511<ul>
1512<li>Android Automotive implementations SHOULD provide an implementation of the
1513Android accessibility framework consistent with the default Android
1514implementation.</li>
1515<li>Device implementations (Android Automotive excluded) MUST provide an
1516implementation of the Android accessibility framework consistent with the
1517default Android implementation.</li>
1518<li>Device implementations (Android Automotive excluded) MUST support
1519third-party accessibility service implementations through the
1520android.accessibilityservice APIs
1521[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1522<li>Device implementations (Android Automotive excluded) MUST generate
1523AccessibilityEvents and deliver these events to all registered
1524AccessibilityService implementations in a manner consistent with the default
1525Android implementation</li>
1526<li> Device implementations (Android Automotive and Android Watch devices with
1527no audio output excluded), MUST provide a user-accessible mechanism to enable
1528and disable accessibility services, and MUST display this interface in response
1529to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1530</ul>
1531
1532<p>Additionally, device implementations SHOULD provide an implementation of an
1533accessibility service on the device, and SHOULD provide a mechanism for users
1534to enable the accessibility service during device setup. An open source
1535implementation of an accessibility service is available from the Eyes Free
1536project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1537
1538<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1539
1540
1541<p>Android includes APIs that allow applications to make use of text-to-speech
1542(TTS) services and allows service providers to provide implementations of TTS
1543services [<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
1544MUST meet these requirements related to the Android TTS framework. </p>
1545
1546<p>Android Automotive implementations:</p>
1547<ul>
1548<li>MUST support the Android TTS framework APIs.</li>
1549<li>MAY support installation of third-party TTS engines. If supported, partners
1550MUST provide a user-accessible interface that allows the user to select a TTS
1551engine for use at system level.</li>
1552</ul>
1553
1554<p>All other device implementations:</p>
1555
1556<ul>
1557 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1558supporting the languages available on the device. Note that the upstream
1559Android open source software includes a full-featured TTS engine
1560implementation.
1561 <li> MUST support installation of third-party TTS engines
1562 <li> MUST provide a user-accessible interface that allows users to select a TTS
1563engine for use at the system level
1564</ul>
1565
1566<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1567
1568
1569<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1570content to Android Television devices. TIF provides a standard API to create
1571input modules that control Android Television devices. Android Television
1572device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1573
1574<p>Device implementations that support TIF MUST declare the platform feature
1575android.software.live_tv.</p>
1576
1577<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1578
1579
1580<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1581by 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>
1582
1583<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
1584files from installing and running correctly on other compatible devices.</p>
1585
1586<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1587
1588
1589<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1590
1591
1592<p>Device implementations MUST support the core media formats specified in the
1593Android 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
1594implementations MUST support the media formats, encoders, decoders, file types,
1595and container formats defined in the tables below and reported via MediaCodecList
1596[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1597Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1598[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1599113</a>].
1600
1601All of these codecs are
1602provided as software implementations in the preferred Android implementation
1603from the Android Open Source Project.</p>
1604
1605<p>Please note that neither Google nor the Open Handset Alliance make any
1606representation that these codecs are free from third-party patents. Those
1607intending to use this source code in hardware or software products are advised
1608that implementations of this code, including in open source software or
1609shareware, may require patent licenses from the relevant patent holders.</p>
1610
1611<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1612
1613<table>
1614 <tr>
1615 <th>Format/Codec</th>
1616 <th>Encoder</th>
1617 <th>Decoder</th>
1618 <th>Details</th>
1619 <th>Supported File Types/Container Formats</th>
1620 </tr>
1621 <tr>
1622 <td>MPEG-4 AAC Profile</p>
1623
1624<p>(AAC LC)</td>
1625 <td>REQUIRED<sup>1</sup></td>
1626 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1627 <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]162848 kHz.</td>
1629 <td>
1630 <ul>
1631 <li class="table_list">3GPP (.3gp)</li>
1632 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1633 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1634supported)</li>
1635 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1636 </tr>
1637 <tr>
1638 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1639 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1640 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1641 <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]1642to 48 kHz.</td>
1643 <td></td>
1644 </tr>
1645 <tr>
1646 <td>MPEG-4 HE AACv2</p>
1647
1648<p>Profile (enhanced AAC+)</td>
1649 <td> </td>
1650 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1651 <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]1652to 48 kHz.</td>
1653 <td></td>
1654 </tr>
1655 <tr>
1656 <td>AAC ELD (enhanced low delay AAC)</td>
1657 <td>REQUIRED<sup>1</sup> </p>
1658
1659<p>(Android 4.1+)</td>
1660 <td>REQUIRED</p>
1661
1662<p>(Android 4.1+)</td>
1663 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1664 <td></td>
1665 </tr>
1666 <tr>
1667 <td>AMR-NB</td>
1668 <td>REQUIRED<sup>3</sup></td>
1669 <td>REQUIRED<sup>3</sup></td>
1670 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1671 <td>3GPP (.3gp)</td>
1672 </tr>
1673 <tr>
1674 <td>AMR-WB</td>
1675 <td>REQUIRED<sup>3</sup></td>
1676 <td>REQUIRED<sup>3</sup></td>
1677 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1678 <td></td>
1679 </tr>
1680 <tr>
1681 <td>FLAC</td>
1682 <td></td>
1683 <td>REQUIRED <br>(Android 3.1+)</td>
1684 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1685recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1686does not include a low-pass filter). 16-bit recommended; no dither applied for
168724-bit.</td>
1688 <td>FLAC (.flac) only</td>
1689 </tr>
1690 <tr>
1691 <td>MP3</td>
1692 <td></td>
1693 <td>REQUIRED</td>
1694 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1695 <td>MP3 (.mp3)</td>
1696 </tr>
1697 <tr>
1698 <td>MIDI</td>
1699 <td></td>
1700 <td>REQUIRED</td>
1701 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1702ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1703 <td><ul>
1704 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1705 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1706 <li class="table_list">OTA (.ota)</li>
1707 <li class="table_list">iMelody (.imy)</li></ul></td>
1708 </tr>
1709 <tr>
1710 <td>Vorbis</td>
1711 <td></td>
1712 <td>REQUIRED</td>
1713 <td></td>
1714 <td><ul>
1715 <li class="table_list">Ogg (.ogg)</li>
1716 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1717 </tr>
1718 <tr>
1719 <td>PCM/WAVE</td>
1720 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1721 <td>REQUIRED</td>
1722 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1723sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1724frequencies.</td>
1725 <td>WAVE (.wav)</td>
1726 </tr>
1727 <tr>
1728 <td>Opus</td>
1729 <td></td>
1730 <td>REQUIRED<br> (Android 5.0+)</td>
1731 <td></td>
1732 <td>Matroska (.mkv)</td>
1733 </tr>
1734</table>
1735
1736
1737<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1738but optional for Android Watch device implementations.</p>
1739
1740<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17412 channels is optional.</p>
1742
1743<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1744
1745<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1746including Android Watch device implementations.</p>
1747
1748<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1749
1750<table>
1751 <tr>
1752 <th>Format/Codec</th>
1753 <th>Encoder</th>
1754 <th>Decoder</th>
1755 <th>Details</th>
1756 <th>Supported File Types/Container Formats</th>
1757 </tr>
1758 <tr>
1759 <td>JPEG</td>
1760 <td>REQUIRED</td>
1761 <td>REQUIRED</td>
1762 <td>Base+progressive</td>
1763 <td>JPEG (.jpg)</td>
1764 </tr>
1765 <tr>
1766 <td>GIF</td>
1767 <td></td>
1768 <td>REQUIRED</td>
1769 <td></td>
1770 <td>GIF (.gif)</td>
1771 </tr>
1772 <tr>
1773 <td>PNG</td>
1774 <td>REQUIRED</td>
1775 <td>REQUIRED</td>
1776 <td></td>
1777 <td>PNG (.png)</td>
1778 </tr>
1779 <tr>
1780 <td>BMP</td>
1781 <td></td>
1782 <td>REQUIRED</td>
1783 <td></td>
1784 <td>BMP (.bmp)</td>
1785 </tr>
1786 <tr>
1787 <td>WebP</td>
1788 <td>REQUIRED</td>
1789 <td>REQUIRED</td>
1790 <td></td>
1791 <td>WebP (.webp)</td>
1792 </tr>
1793</table>
1794
1795
1796<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1797
1798<p>Video codecs are optional for Android Watch device implementations.</p>
1799
1800<table>
1801 <tr>
1802 <th>Format/Codec</th>
1803 <th>Encoder</th>
1804 <th>Decoder</th>
1805 <th>Details</th>
1806 <th>Supported File Types/<br>Container Formats</th>
1807 </tr>
1808 <tr>
1809 <td>H.263</td>
1810 <td>REQUIRED<sup>1</sup></td>
1811 <td>REQUIRED<sup>2</sup></td>
1812 <td></td>
1813 <td><ul>
1814 <li class="table_list">3GPP (.3gp)</li>
1815 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1816 </tr>
1817 <tr>
1818 <td>H.264 AVC</td>
1819 <td>REQUIRED<sup>2</sup></td>
1820 <td>REQUIRED<sup>2</sup></td>
1821 <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>
1822 <td><ul>
1823 <li class="table_list">3GPP (.3gp)</li>
1824 <li class="table_list">MPEG-4 (.mp4)</li>
1825 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1826 </tr>
1827 <tr>
1828 <td>H.265 HEVC</td>
1829 <td></td>
1830 <td>REQUIRED<sup>5</sup></td>
1831 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1832 <td>MPEG-4 (.mp4)</td>
1833 </tr>
1834 <tr>
1835 <td>MPEG-4 SP</td>
1836 <td></td>
1837 <td>REQUIRED<sup>2</sup></td>
1838 <td></td>
1839 <td>3GPP (.3gp)</td>
1840 </tr>
1841 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1842 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1843 <td>REQUIRED<sup>2</sup></p>
1844
1845<p>(Android 4.3+)</td>
1846 <td>REQUIRED<sup>2</sup></p>
1847
1848<p>(Android 2.3.3+)</td>
1849 <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>
1850 <td><ul>
1851 <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]1852 <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]1853 </tr>
1854 <tr>
1855 <td>VP9</td>
1856 <td></td>
1857 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1858 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1859 <td><ul>
1860 <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]1861 <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]1862 </tr>
1863</table>
1864
1865
1866<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1867android.hardware.camera or android.hardware.camera.front.</p>
1868
1869<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1870
1871<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1872device implementations SHOULD use a hardware VP8 codec that meets the
1873requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1874
1875<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1876
1877<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1878
1879<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1880
1881<div class="note">
1882<p>Video codecs are optional for Android Watch device implementations.</p>
1883</div>
1884
1885
1886<p>Android device implementations with H.264 codec support, MUST support Baseline
1887Profile Level 3 and the following SD (Standard Definition) video encoding
1888profiles and SHOULD support Main Profile Level 4 and the following HD (High
1889Definition) video encoding profiles. Android Television devices are STRONGLY
1890RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1891<table>
1892 <tr>
1893 <th></th>
1894 <th>SD (Low quality)</th>
1895 <th>SD (High quality)</th>
1896 <th>HD 720p1</th>
1897 <th>HD 1080p1</th>
1898 </tr>
1899 <tr>
1900 <th>Video resolution</th>
1901 <td>320 x 240 px</td>
1902 <td>720 x 480 px</td>
1903 <td>1280 x 720 px</td>
1904 <td>1920 x 1080 px</td>
1905 </tr>
1906 <tr>
1907 <th>Video frame rate</th>
1908 <td>20 fps</td>
1909 <td>30 fps</td>
1910 <td>30 fps</td>
1911 <td>30 fps</td>
1912 </tr>
1913 <tr>
1914 <th>Video bitrate</th>
1915 <td>384 Kbps</td>
1916 <td>2 Mbps</td>
1917 <td>4 Mbps</td>
1918 <td>10 Mbps</td>
1919 </tr>
1920</table>
1921
1922
1923<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1924devices.</p>
1925
1926<p>Android device implementations with VP8 codec support MUST support the SD video
1927encoding profiles and SHOULD support the following HD (High Definition) video
1928encoding profiles.</p>
1929<table>
1930 <tr>
1931 <th></th>
1932 <th>SD (Low quality)</th>
1933 <th>SD (High quality)</th>
1934 <th>HD 720p1</th>
1935 <th>HD 1080p1</th>
1936 </tr>
1937 <tr>
1938 <th>Video resolution</th>
1939 <td>320 x 180 px</td>
1940 <td>640 x 360 px</td>
1941 <td>1280 x 720 px</td>
1942 <td>1920 x 1080 px</td>
1943 </tr>
1944 <tr>
1945 <th>Video frame rate</th>
1946 <td>30 fps</td>
1947 <td>30 fps</td>
1948 <td>30 fps</td>
1949 <td>30 fps</td>
1950 </tr>
1951 <tr>
1952 <th>Video bitrate</th>
1953 <td>800 Kbps </td>
1954 <td>2 Mbps</td>
1955 <td>4 Mbps</td>
1956 <td>10 Mbps</td>
1957 </tr>
1958</table>
1959
1960<p class="table_footnote">1 When supported by hardware.</p>
1961
1962<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1963
1964<div class="note">
1965<p>Video codecs are optional for Android Watch device implementations.</p>
1966</div>
1967
1968
1969<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1970the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1971standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1972
1973<p>Android device implementations with H.264 decoders, MUST support Baseline
1974Profile Level 3 and the following SD video decoding profiles and SHOULD support
1975the HD decoding profiles. Android Television devices MUST support High Profile
1976Level 4.2 and the HD 1080p decoding profile.</p>
1977<table>
1978 <tr>
1979 <th></th>
1980 <th>SD (Low quality)</th>
1981 <th>SD (High quality)</th>
1982 <th>HD 720p1</th>
1983 <th>HD 1080p1</th>
1984 </tr>
1985 <tr>
1986 <th>Video resolution</th>
1987 <td>320 x 240 px</td>
1988 <td>720 x 480 px</td>
1989 <td>1280 x 720 px</td>
1990 <td>1920 x 1080 px</td>
1991 </tr>
1992 <tr>
1993 <th>Video frame rate</th>
1994 <td>30 fps</td>
1995 <td>30 fps</td>
1996 <td>30 fps / 60 fps2</td>
1997 <td>30 fps / 60 fps2</td>
1998 </tr>
1999 <tr>
2000 <th>Video bitrate</th>
2001 <td>800 Kbps </td>
2002 <td>2 Mbps</td>
2003 <td>8 Mbps</td>
2004 <td>20 Mbps</td>
2005 </tr>
2006</table>
2007
2008
2009<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2010types only when supported by hardware.</p>
2011
2012<p class="table_footnote">2 Required for Android Television device implementations.</p>
2013
2014<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
2015decoding profiles. Android Television devices MUST support the HD 1080p
2016decoding profile. </p>
2017<table>
2018 <tr>
2019 <th></th>
2020 <th>SD (Low quality)</th>
2021 <th>SD (High quality)</th>
2022 <th>HD 720p1</th>
2023 <th>HD 1080p1</th>
2024 </tr>
2025 <tr>
2026 <th>Video resolution</th>
2027 <td>320 x 180 px</td>
2028 <td>640 x 360 px</td>
2029 <td>1280 x 720 px</td>
2030 <td>1920 x 1080 px</td>
2031 </tr>
2032 <tr>
2033 <th>Video frame rate</th>
2034 <td>30 fps</td>
2035 <td>30 fps</td>
2036 <td>30 fps / 60 fps2</td>
2037 <td>30 / 60 fps2</td>
2038 </tr>
2039 <tr>
2040 <th>Video bitrate</th>
2041 <td>800 Kbps </td>
2042 <td>2 Mbps</td>
2043 <td>8 Mbps</td>
2044 <td>20 Mbps</td>
2045 </tr>
2046</table>
2047
2048
2049<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2050devices only when supported by hardware.</p>
2051
2052<p class="table_footnote">2 Required for Android Television device implementations.</p>
2053
2054<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
2055HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2056support the HD 1080p decoding profile and SHOULD support the UHD decoding
2057profile. When the UHD video decoding profile is supported, it MUST support 8
2058bit color depth.</p>
2059<table>
2060 <tr>
2061 <th></th>
2062 <th>SD (Low quality)</th>
2063 <th>SD (High quality)</th>
2064 <th>HD 720p 1</th>
2065 <th>HD 1080p 2</th>
2066 <th>UHD 2</th>
2067 </tr>
2068 <tr>
2069 <th>Video resolution</th>
2070 <td>320 x 180 px</td>
2071 <td>640 x 360 px</td>
2072 <td>1280 x 720 px</td>
2073 <td>1920 x 1080 px</td>
2074 <td>3840 x 2160 px</td>
2075 </tr>
2076 <tr>
2077 <th>Video frame rate</th>
2078 <td>30 fps</td>
2079 <td>30 fps</td>
2080 <td>30 fps</td>
2081 <td>30 fps</td>
2082 <td>30 fps</td>
2083 </tr>
2084 <tr>
2085 <th>Video bitrate</th>
2086 <td>600 Kbps </td>
2087 <td>1.6 Mbps</td>
2088 <td>4 Mbps</td>
2089 <td>10 Mbps</td>
2090 <td>20 Mbps</td>
2091 </tr>
2092</table>
2093
2094
2095<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2096devices only when supported by hardware.</p>
2097
2098<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2099supported by hardware.</p>
2100
2101<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
2102decoding profiles and SHOULD support the HD decoding profiles. Android
2103Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21041080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2105the UHD decoding profile.</p>
2106<table>
2107 <tr>
2108 <th></th>
2109 <th>SD (Low quality)</th>
2110 <th>SD (High quality)</th>
2111 <th>HD 720p </strong>1 </td>
2112 <th>HD 1080p </strong>1 </td>
2113 <th>UHD </strong>2</td>
2114 </tr>
2115 <tr>
2116 <th>Video resolution</th>
2117 <td>352 x 288 px</td>
2118 <td>640 x 360 px</td>
2119 <td>1280 x 720 px</td>
2120 <td>1920 x 1080 px</td>
2121 <td>3840 x 2160 px</td>
2122 </tr>
2123 <tr>
2124 <th>Video frame rate</th>
2125 <td>30 fps</td>
2126 <td>30 fps</td>
2127 <td>30 fps</td>
2128 <td>30 fps</td>
2129 <td>30 fps</td>
2130 </tr>
2131 <tr>
2132 <th>Video bitrate</th>
2133 <td>600 Kbps </td>
2134 <td>1.6 Mbps</td>
2135 <td>4 Mbps</td>
2136 <td>10 Mbps</td>
2137 <td>20 Mbps</td>
2138 </tr>
2139</table>
2140
2141
2142<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2143devices only when supported by hardware.</p>
2144
2145<p class="table_footnote">2 Required for Android Television device implementations when supported by
2146hardware.</p>
2147
2148<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2149
2150
2151<p>While some of the requirements outlined in this section are stated as SHOULD
2152since Android 4.3, the Compatibility Definition for a future version is planned
2153to 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
2154compatibility when upgraded to the future version.</p>
2155
2156<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2157
2158
2159<p>Device implementations that declare android.hardware.microphone MUST allow
2160capture of raw audio content with the following characteristics:</p>
2161
2162<ul>
2163 <li><strong>Format</strong>: Linear PCM, 16-bit
2164 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2165 <li><strong>Channels</strong>: Mono
2166</ul>
2167
2168<p>Device implementations that declare android.hardware.microphone SHOULD allow
2169capture of raw audio content with the following characteristics:</p>
2170
2171<ul>
2172 <li><strong>Format</strong>: Linear PCM, 16-bit
2173 <li><strong>Sampling rates</strong>: 22050, 48000
2174 <li><strong>Channels</strong>: Stereo
2175</ul>
2176
2177<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2178
2179
2180<p>In addition to the above recording specifications, when an application has
2181started recording an audio stream using the
2182android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2183
2184<ul>
2185 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2186characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2187 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2188source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2189 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2190dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2191 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2192level at the microphone.
2193 <li>Noise reduction processing, if present, MUST be disabled.
2194 <li>Automatic gain control, if present, MUST be disabled
2195</ul>
2196
2197<p>If the platform supports noise suppression technologies tuned for speech
2198recognition, the effect MUST be controllable from the
2199android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2200noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2201of the noise suppression technology.</p>
2202
2203<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2204
2205
2206<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2207audio source. Devices that declare android.hardware.audio.output MUST properly
2208implement the REMOTE_SUBMIX audio source so that when an application uses the
2209android.media.AudioRecord API to record from this audio source, it can capture
2210a mix of all audio streams except for the following:</p>
2211
2212<ul>
2213 <li>STREAM_RING
2214 <li>STREAM_ALARM
2215 <li>STREAM_NOTIFICATION
2216</ul>
2217
2218<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2219
2220
2221<p>Device implementations that declare android.hardware.audio.output MUST conform
2222to the requirements in this section.</p>
2223
2224<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2225
2226
2227<p>The device MUST allow playback of raw audio content with the following
2228characteristics:</p>
2229
2230<ul>
2231 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2232 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2233 <li><strong>Channels</strong>: Mono, Stereo</li>
2234</ul>
2235
2236<p>The device SHOULD allow playback of raw audio content with the following
2237characteristics:</p>
2238
2239<ul>
2240 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2241</ul>
2242
2243<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2244
2245
2246<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
2247android.hardware.audio.output:</p>
2248
2249<ul>
2250 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2251implementations controllable through the AudioEffect subclasses Equalizer,
2252LoudnessEnhancer.</li>
2253 <li>MUST support the visualizer API implementation, controllable through the
2254Visualizer class.</li>
2255 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2256EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2257controllable through the AudioEffect sub-classes BassBoost,
2258EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2259</ul>
2260
2261<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2262
2263
2264<p>Android Television device implementations MUST include support for system
2265Master Volume and digital audio output volume attenuation on supported outputs,
2266except for compressed audio passthrough output (where no audio decoding is done
2267on the device).</p>
2268
2269<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2270
2271
2272<p>Audio latency is the time delay as an audio signal passes through a system.
2273Many classes of applications rely on short latencies, to achieve real-time
2274sound effects.</p>
2275
2276<p>For the purposes of this section, use the following definitions:</p>
2277
2278<ul>
2279 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2280when the corresponding sound can be heard by an external listener or observed
2281by a transducer.</li>
2282 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2283idle and powered down prior to the request.</li>
2284 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2285 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2286when an application reads the corresponding frame of PCM-coded data.</li>
2287 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2288audio input system has been idle and powered down prior to the request.</li>
2289 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2290 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2291 <li><strong>cold input jitter</strong>. The variance among separate measurements of cold input latency values.</li>
2292 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus 5
2293milliseconds.</li>
2294 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2295NDK_root/docs/opensles/index.html.</li>
2296</ul>
2297
2298<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2299or exceed these audio output requirements:</p>
2300
2301<ul>
2302 <li>cold output latency of 100 milliseconds or less</li>
2303 <li>continuous output latency of 45 milliseconds or less</li>
2304 <li>minimize the cold output jitter</li>
2305</ul>
2306
2307<p>If a device implementation meets the requirements of this section after any
2308initial calibration when using the OpenSL ES PCM buffer queue API, for
2309continuous output latency and cold output latency over at least one supported
2310audio output device, it MAY report support for low-latency audio, by reporting
2311the feature android.hardware.audio.low_latency via the
2312android.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
2313MUST NOT report support for low-latency audio.</p>
2314
2315<p>Device implementations that include android.hardware.microphone SHOULD meet
2316these input audio requirements:</p>
2317
2318<ul>
2319 <li>cold input latency of 100 milliseconds or less</li>
2320 <li>continuous input latency of 30 milliseconds or less</li>
2321 <li>continuous round-trip latency of 50 milliseconds or less</li>
2322 <li>minimize the cold input jitter</li>
2323</ul>
2324
2325<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2326
2327
2328<p>Devices MUST support the media network protocols for audio and video playback
2329as 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>
2330
2331<ul>
2332 <li>RTSP (RTP, SDP)</li>
2333 <li>HTTP(S) progressive streaming</li>
2334 <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>
2335</ul>
2336
2337<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2338
2339
2340<p>Device implementations that support secure video output and are capable of
2341supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2342implementations that declare support for Display.FLAG_SECURE, if they support a
2343wireless display protocol, MUST secure the link with a cryptographically strong
2344mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2345if they support a wired external display, the device implementations MUST
2346support HDCP 1.2 or higher. Android Television device implementations MUST
2347support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2348lower resolutions. The upstream Android open source implementation includes
2349support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2350requirement.</p>
2351
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2352<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2353
2354<p>
2355If a device implementation supports the inter-app MIDI software transport
2356(virtual MIDI devices), and it supports MIDI over
2357<em>all</em> of the following MIDI-capable hardware transports
2358for which it provides generic non-MIDI connectivity, it MAY report
2359support for feature android.software.midi via the
2360android.content.pm.PackageManager class
2361[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2362</p>
2363
2364<p>The MIDI-capable hardware transports are:</p>
2365<ul>
2366 <li>USB host mode (section 7.7 USB)</li>
2367 <li>USB peripheral mode (section 7.7 USB)</li>
2368</ul>
2369
2370<p>
2371Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2372MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2373it MUST NOT report support for feature android.software.midi.
2374</p>
2375
2376<p>
2377MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2378is in trial use status. A device implementation that reports
2379feature android.software.midi, and which provides generic non-MIDI connectivity
2380over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2381</p>
2382
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2383<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2384
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2385<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2386
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2387<p>Device implementations MUST support the Android Developer Tools provided in the
2388Android SDK. Android compatible devices MUST be compatible with:</p>
2389
2390<ul>
2391 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2392</ul>
2393
2394<p>Device implementations MUST support all adb functions as documented in the
2395Android 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
2396user-accessible mechanism to turn on the Android Debug Bridge. If a device
2397implementation omits USB peripheral mode, it MUST implement the Android Debug
2398Bridge via local-area network (such as Ethernet or 802.11). </p>
2399
2400<p>Android includes support for secure adb. Secure adb enables adb on known
2401authenticated hosts. Device implementations MUST support secure adb.</p>
2402
2403<ul>
2404 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2405</ul>
2406
2407<p>Device implementations MUST support all ddms features as documented in the
2408Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2409but MUST be supported whenever the user has activated the Android Debug Bridge,
2410as above.</p>
2411
2412<ul>
2413 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2414</ul>
2415
2416<p>Device implementations MUST include the Monkey framework, and make it available
2417for applications to use.</p>
2418
2419<ul>
2420 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2421</ul>
2422
2423<p>Device implementations MUST support systrace tool as documented in the Android
2424SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2425mechanism to turn on Systrace.</p>
2426
2427<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2428using the standard Android SDK tools, without additional support; however
2429Microsoft Windows systems typically require a driver for new Android devices.
2430(For instance, new vendor IDs and sometimes new device IDs require custom USB
2431drivers for Windows systems.) If a device implementation is unrecognized by the
2432adb tool as provided in the standard Android SDK, device implementers MUST
2433provide Windows drivers allowing developers to connect to the device using the
2434adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2435Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2436
2437<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2438
2439
2440<p>Android includes support for developers to configure application
2441development-related settings. Device implementations MUST honor the
2442android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2443development-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
2444default and enables users to launch Developer Options after pressing seven (7)
2445times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2446Developer Options. Specifically, device implementations MUST hide Developer
2447Options by default and MUST provide a mechanism to enable Developer Options
2448that is consistent with the upstream Android implementation.</p>
2449
2450<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2451
2452
2453<p>If a device includes a particular hardware component that has a corresponding
2454API for third-party developers, the device implementation MUST implement that
2455API as described in the Android SDK documentation. If an API in the SDK
2456interacts with a hardware component that is stated to be optional and the
2457device implementation does not possess that component:</p>
2458
2459<ul>
2460 <li>Complete class definitions (as documented by the SDK) for the component APIs
2461MUST still be presented.
2462 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2463 <li>API methods MUST return null values where permitted by the SDK documentation.
2464 <li>API methods MUST return no-op implementations of classes where null values are
2465not permitted by the SDK documentation.
2466 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2467</ul>
2468
2469<p>A typical example of a scenario where these requirements apply is the telephony
2470API: even on non-phone devices, these APIs must be implemented as reasonable
2471no-ops.</p>
2472
2473<p>Device implementations MUST consistently report accurate hardware configuration
2474information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2475methods on the android.content.pm.PackageManager class for the same build
2476fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2477
2478<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2479
2480
2481<p>Android includes facilities that automatically adjust application assets and UI
2482layouts appropriately for the device, to ensure that third-party applications
2483run 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
2484this section.</p>
2485
2486<p>The units referenced by the requirements in this section are defined as
2487follows:</p>
2488
2489<ul>
2490 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2491of the display.</li>
2492 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
24931&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2494within the range.</li>
2495 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2496 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2497 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2498 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2499dps * (density/160).</li>
2500</ul>
2501
2502<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2503
2504
2505<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2506
2507<div class="note">
2508<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>
2509</div>
2510
2511<p>The Android UI framework supports a variety of different screen sizes, and
2512allows applications to query the device screen size (aka &ldquo;screen layout") via
2513android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2514Device implementations MUST report the correct screen size as defined in the
2515Android 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
2516implementations MUST report the correct screen size according to the following
2517logical density-independent pixel (dp) screen dimensions.</p>
2518
2519<ul>
2520 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2521is an Android Watch device.</li>
2522 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2523dp x 320 dp.</li>
2524 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2525dp x 480 dp.</li>
2526 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2527dp x 720 dp.</li>
2528</ul>
2529
2530<p>In addition, </p>
2531
2532<ul>
2533 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2534range from 1.1 to 2.5 inches.</li>
2535 <li>Other types of Android device implementations, with a physically integrated
2536screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2537</ul>
2538
2539<p>Devices MUST NOT change their reported screen size at any time.</p>
2540
2541<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2542&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2543implementations MUST correctly honor applications' stated support for small,
2544normal, large, and xlarge screens, as described in the Android SDK
2545documentation.</p>
2546
2547<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2548
2549<div class="note">
2550<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2551</div>
2552
2553
2554<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
255516:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2556such a device implementation will use a UI_MODE_TYPE_WATCH as the
2557android.content.res.Configuration.uiMode.</p>
2558
2559<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2560
2561
2562<p>The Android UI framework defines a set of standard logical densities to help
2563application developers target application resources. Device implementations
2564MUST report only one of the following logical Android framework densities
2565through the android.util.DisplayMetrics APIs, and MUST execute applications at
2566this standard density and MUST NOT change the value at at any time for the
2567default display.</p>
2568
2569<ul>
2570 <li>120 dpi (ldpi)</li>
2571 <li>160 dpi (mdpi)</li>
2572 <li>213 dpi (tvdpi)</li>
2573 <li>240 dpi (hdpi)</li>
2574 <li>280 dpi (280dpi)</li>
2575 <li>320 dpi (xhdpi)</li>
2576 <li>400 dpi (400dpi)</li>
2577 <li>480 dpi (xxhdpi)</li>
2578 <li>560 dpi (560dpi)</li>
2579 <li>640 dpi (xxxhdpi)</li>
2580</ul>
2581
2582<p>Device implementations SHOULD define the standard Android framework density
2583that is numerically closest to the physical density of the screen, unless that
2584logical density pushes the reported screen size below the minimum supported. If
2585the standard Android framework density that is numerically closest to the
2586physical density results in a screen size that is smaller than the smallest
2587supported compatible screen size (320 dp width), device implementations SHOULD
2588report the next lowest standard Android framework density.</p>
2589
2590<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2591
2592
2593<p>Device implementations MUST report correct values for all display metrics
2594defined 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
2595external screen is used as the default display.</p>
2596
2597<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2598
2599
2600<p>Devices MUST report which screen orientations they support
2601(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2602MUST report at least one supported orientation. For example, a device with a
2603fixed orientation landscape screen, such as a television or laptop, SHOULD only
2604report android.hardware.screen.landscape.</p>
2605
2606<p>Devices that report both screen orientations MUST support dynamic orientation
2607by applications to either portrait or landscape screen orientation. That is,
2608the device must respect the application&rsquo;s request for a specific screen
2609orientation. Device implementations MAY select either portrait or landscape
2610orientation as the default.</p>
2611
2612<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2613whenever queried via the android.content.res.Configuration.orientation,
2614android.view.Display.getOrientation(), or other APIs.</p>
2615
2616<p>Devices MUST NOT change the reported screen size or density when changing
2617orientation.</p>
2618
2619<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2620
2621
2622<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2623detailed in the Android SDK documentations. Device implementations SHOULD
2624support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2625implementations MUST also support Android RenderScript, as detailed in the
2626Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2627
2628<p>Device implementations MUST also correctly identify themselves as supporting
2629OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2630
2631<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2632 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2633for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2634 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2635libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2636ES 2.0.</li>
2637 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2638support the corresponding managed APIs and include support for native C/C++
2639APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2640libGLESv2.so MUST export the corresponding function symbols in addition to the
2641OpenGL ES 2.0 function symbols.</li>
2642</ul>
2643
2644<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2645interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2646and the ASTC texture compression format. Android device implementations MAY
2647support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2648support through the android.hardware.opengles.aep feature flag.</p>
2649
2650<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2651However, device implementations MUST report via the OpenGL ES managed and
2652native APIs all extension strings that they do support, and conversely MUST NOT
2653report extension strings that they do not support.</p>
2654
2655<p>Note that Android includes support for applications to optionally specify that
2656they require specific OpenGL texture compression formats. These formats are
2657typically vendor-specific. Device implementations are not required by Android
2658to implement any specific texture compression format. However, they SHOULD
2659accurately report any texture compression formats that they do support, via the
2660getString() method in the OpenGL API.</p>
2661
2662<p>Android includes a mechanism for applications to declare that they want to
2663enable hardware acceleration for 2D graphics at the Application, Activity,
2664Window, or View level through the use of a manifest tag
2665android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2666
2667<p>Device implementations MUST enable hardware acceleration by default, and MUST
2668disable hardware acceleration if the developer so requests by setting
2669android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2670through the Android View APIs.</p>
2671
2672<p>In addition, device implementations MUST exhibit behavior consistent with the
2673Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2674
2675<p>Android includes a TextureView object that lets developers directly integrate
2676hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2677Device implementations MUST support the TextureView API, and MUST exhibit
2678consistent behavior with the upstream Android implementation.</p>
2679
2680<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2681that indicates whether the EGLConfig supports rendering to an ANativeWindow
2682that records images to a video. Device implementations MUST support
2683EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2684
2685<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2686
2687
2688<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2689'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2690applications not developed for old versions of Android that pre-date
2691screen-size independence.</p>
2692
2693<ul>
2694<li>Android Automotive does not support legacy compatibility mode.</li>
2695<li>All other device implementations MUST include support for legacy application
2696compatibility mode as implemented by the upstream Android open source code. That
2697is, device implementations MUST NOT alter the triggers or thresholds at which
2698compatibility mode is activated, and MUST NOT alter the behavior of the
2699compatibility mode itself.</li>
2700</ul>
2701
2702<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2703
2704
2705<p>The Android platform includes APIs that allow applications to render rich
2706graphics to the display. Devices MUST support all of these APIs as defined by
2707the Android SDK unless specifically allowed in this document. </p>
2708
2709<ul>
2710 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2711SHOULD support displays capable of 24-bit color graphics.</li>
2712 <li>Devices MUST support displays capable of rendering animations.</li>
2713 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2714and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
271515% tolerance.</li>
2716</ul>
2717
2718<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2719
2720
2721<p>Android includes support for secondary display to enable media sharing
2722capabilities and developer APIs for accessing external displays. If a device
2723supports an external display either via a wired, wireless, or an embedded
2724additional display connection then the device implementation MUST implement the
2725display 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>
2726
2727<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2728
2729<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2730for non-touch navigation.</p>
2731
2732<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2733
2734<div class="note">
2735<p>Android Watch and Android Automotive implementations MAY implement a soft
2736keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2737</div>
2738
2739
2740<p>Device implementations:</p>
2741
2742<ul>
2743 <li>MUST include support for the Input Management Framework (which allows
2744third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2745detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2746 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2747hard keyboard is present) except for Android Watch devices where the screen
2748size makes it less reasonable to have a soft keyboard.</li>
2749 <li>MAY include additional soft keyboard implementations.</li>
2750 <li>MAY include a hardware keyboard.</li>
2751 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2752specified 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>
2753</ul>
2754
2755<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2756
2757<div class="note">
2758<p>Android Television devices MUST support D-pad.</p>
2759</div>
2760
2761<p>Device implementations:</p>
2762
2763<ul>
2764 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2765device implementation is not an Android Television device.</li>
2766 <li>MUST report the correct value for android.content.res.Configuration.navigation
2767[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2768 <li>MUST provide a reasonable alternative user interface mechanism for the
2769selection and editing of text, compatible with Input Management Engines. The
2770upstream Android open source implementation includes a selection mechanism
2771suitable for use with devices that lack non-touch navigation inputs.</li>
2772</ul>
2773
2774<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2775
2776<div class="note">
2777<p>The availability and visibility requirement of the Home, Recents, and Back
2778functions differ between device types as described in this section.</p>
2779</div>
2780
2781<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2782KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2783navigation paradigm and therefore:</p>
2784
2785<ul>
2786 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2787Back functions.</li>
2788 <li>Android Television device implementations MUST provide the Home and Back
2789functions.</li>
2790 <li>Android Watch device implementations MUST have the Home function available to
2791the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2792 <li>Android Automotive implementations MUST provide the Home function and MAY
2793provide Back and Recent functions.</li>
2794 <li>All other types of device implementations MUST provide the Home and Back
2795functions.</li>
2796</ul>
2797
2798<p>These functions MAY be implemented via dedicated physical buttons (such as
2799mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2800software keys on a distinct portion of the screen, gestures, touch panel, etc.
2801Android supports both implementations. All of these functions MUST be
2802accessible with a single action (e.g. tap, double-click or gesture) when
2803visible.</p>
2804
2805<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2806together with other navigation functions in full-screen mode. This does not
2807apply to devices upgrading from earlier Android versions that have physical
2808buttons for navigation and no recents key.</p>
2809
2810<p> The Home and Back functions, if provided, MUST each have a visible button or
2811icon unless hidden together with other navigation functions in full-screen mode
2812or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2813
2814<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2815Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2816implement a dedicated physical button for the Menu function. Older device
2817implementations SHOULD NOT implement a dedicated physical button for the Menu
2818function, but if the physical Menu button is implemented and the device is
2819running applications with targetSdkVersion > 10, the device implementation:</p>
2820
2821<ul>
2822 <li>MUST display the action overflow button on the action bar when it is visible
2823and the resulting action overflow menu popup is not empty. For a device
2824implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2825is RECOMMENDED.</li>
2826 <li>MUST NOT modify the position of the action overflow popup displayed by
2827selecting the overflow button in the action bar.</li>
2828 <li>MAY render the action overflow popup at a modified position on the screen when
2829it is displayed by selecting the physical menu button.</li>
2830</ul>
2831
2832<p>For backwards compatibility, device implementations MUST make the Menu function
2833available to applications when targetSdkVersion is less than 10, either by a physical
2834button, a software key, or gestures. This Menu function should be presented
2835unless hidden together with other navigation functions.</p>
2836
2837<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
2838the Assist action available to the user at all times when running applications.
2839The Assist action SHOULD be implemented as a long-press on the Home button or a
2840swipe-up gesture on the software Home key. This function MAY be implemented via
2841another physical button, software key, or gesture, but MUST be accessible with
2842a single action (e.g. tap, double-click, or gesture) when other navigation keys
2843are visible.</p>
2844
2845<p>Device implementations MAY use a distinct portion of the screen to display the
2846navigation keys, but if so, MUST meet these requirements:</p>
2847
2848<ul>
2849 <li>Device implementation navigation keys MUST use a distinct portion of the
2850screen, not available to applications, and MUST NOT obscure or otherwise
2851interfere with the portion of the screen available to applications.</li>
2852 <li>Device implementations MUST make available a portion of the display to
2853applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2854 <li>Device implementations MUST display the navigation keys when applications do
2855not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2856 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2857profile&rdquo; (eg. dimmed) mode when applications specify
2858SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2859 <li>Device implementations MUST hide the navigation keys when applications specify
2860SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2861</ul>
2862
2863<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2864
2865<div class="note">
2866<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2867</div>
2868
2869
2870<p>Device implementations SHOULD have a pointer input system of some kind (either
2871mouse-like or touch). However, if a device implementation does not support a
2872pointer input system, it MUST NOT report the android.hardware.touchscreen or
2873android.hardware.faketouch feature constant. Device implementations that do
2874include a pointer input system:</p>
2875
2876<ul>
2877 <li>SHOULD support fully independently tracked pointers, if the device input system
2878supports multiple pointers.</li>
2879 <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>
2880</ul>
2881
2882<p>Android includes support for a variety of touchscreens, touch pads, and fake
2883touch input devices. Touchscreen based device implementations are associated
2884with 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
2885screen. Since the user is directly touching the screen, the system does not
2886require any additional affordances to indicate the objects being manipulated.
2887In contrast, a fake touch interface provides a user input system that
2888approximates a subset of touchscreen capabilities. For example, a mouse or
2889remote control that drives an on-screen cursor approximates touch, but requires
2890the user to first point or focus then click. Numerous input devices like the
2891mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2892trackpad can support fake touch interactions. Android includes the feature
2893constant android.hardware.faketouch, which corresponds to a high-fidelity
2894non-touch (pointer-based) input device such as a mouse or trackpad that can
2895adequately emulate touch-based input (including basic gesture support), and
2896indicates that the device supports an emulated subset of touchscreen
2897functionality. Device implementations that declare the fake touch feature MUST
2898meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2899
2900<p>Device implementations MUST report the correct feature corresponding to the
2901type of input used. Device implementations that include a touchscreen
2902(single-touch or better) MUST report the platform feature constant
2903android.hardware.touchscreen. Device implementations that report the platform
2904feature constant android.hardware.touchscreen MUST also report the platform
2905feature constant android.hardware.faketouch. Device implementations that do not
2906include a touchscreen (and rely on a pointer device only) MUST NOT report any
2907touchscreen feature, and MUST report only android.hardware.faketouch if they
2908meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2909
2910<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2911
2912
2913<p>Device implementations that declare support for android.hardware.faketouch:</p>
2914
2915<ul>
2916 <li>MUST report the absolute X and Y screen positions of the pointer location and
2917display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2918 <li>MUST report touch event with the action code that specifies the state change
2919that 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>
2920 <li>MUST support pointer down and up on an object on the screen, which allows users
2921to emulate tap on an object on the screen.</li>
2922 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2923place on an object on the screen within a time threshold, which allows users to
2924emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2925 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2926any other arbitrary point on the screen, followed by a pointer up, which allows
2927users to emulate a touch drag.</li>
2928 <li>MUST support pointer down then allow users to quickly move the object to a
2929different position on the screen and then pointer up on the screen, which
2930allows users to fling an object on the screen.</li>
2931</ul>
2932
2933<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2934MUST meet the requirements for faketouch above, and MUST also support distinct
2935tracking of two or more independent pointer inputs.</p>
2936
2937<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
2938
2939
2940<p>Android Television device implementations MUST support button mappings for game
2941controllers as listed below. The upstream Android implementation includes
2942implementation for game controllers that satisfies this requirement. </p>
2943
2944<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
2945
2946
2947<p>Android Television device implementations MUST support the following key
2948mappings:</p>
2949<table>
2950 <tr>
2951 <th>Button</th>
2952 <th>HID Usage</strong><sup>2</sup></td>
2953 <th>Android Button</th>
2954 </tr>
2955 <tr>
2956 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
2957 <td>0x09 0x0001</td>
2958 <td>KEYCODE_BUTTON_A (96)</td>
2959 </tr>
2960 <tr>
2961 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
2962 <td>0x09 0x0002</td>
2963 <td>KEYCODE_BUTTON_B (97)</td>
2964 </tr>
2965 <tr>
2966 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
2967 <td>0x09 0x0004</td>
2968 <td>KEYCODE_BUTTON_X (99)</td>
2969 </tr>
2970 <tr>
2971 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
2972 <td>0x09 0x0005</td>
2973 <td>KEYCODE_BUTTON_Y (100)</td>
2974 </tr>
2975 <tr>
2976 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
2977
2978<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]2979 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2980 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
2981 </tr>
2982 <tr>
2983 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
2984
2985<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]2986 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2987 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
2988 </tr>
2989 <tr>
2990 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
2991 <td>0x09 0x0007</td>
2992 <td>KEYCODE_BUTTON_L1 (102)</td>
2993 </tr>
2994 <tr>
2995 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
2996 <td>0x09 0x0008</td>
2997 <td>KEYCODE_BUTTON_R1 (103)</td>
2998 </tr>
2999 <tr>
3000 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3001 <td>0x09 0x000E</td>
3002 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3003 </tr>
3004 <tr>
3005 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3006 <td>0x09 0x000F</td>
3007 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3008 </tr>
3009 <tr>
3010 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3011 <td>0x0c 0x0223</td>
3012 <td>KEYCODE_HOME (3)</td>
3013 </tr>
3014 <tr>
3015 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3016 <td>0x0c 0x0224</td>
3017 <td>KEYCODE_BACK (4)</td>
3018 </tr>
3019</table>
3020
3021
3022<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3023
3024<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3025
3026<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3027Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3028Report Size of 4. The logical value is defined to be the clockwise rotation
3029away from the vertical axis; for example, a logical value of 0 represents no
3030rotation and the up button being pressed, while a logical value of 1 represents
3031a rotation of 45 degrees and both the up and left keys being pressed.</p>
3032
3033<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3034
3035<table>
3036 <tr>
3037 <th>Analog Controls</strong><sup>1</sup></td>
3038 <th>HID Usage</th>
3039 <th>Android Button</th>
3040 </tr>
3041 <tr>
3042 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3043 <td>0x02 0x00C5</td>
3044 <td>AXIS_LTRIGGER </td>
3045 </tr>
3046 <tr>
3047 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3048 <td>0x02 0x00C4</td>
3049 <td>AXIS_RTRIGGER </td>
3050 </tr>
3051 <tr>
3052 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3053 <td>0x01 0x0030</p>
3054
3055<p>0x01 0x0031</td>
3056 <td>AXIS_X</p>
3057
3058<p>AXIS_Y</td>
3059 </tr>
3060 <tr>
3061 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3062 <td>0x01 0x0032</p>
3063
3064<p>0x01 0x0035</td>
3065 <td>AXIS_Z</p>
3066
3067<p>AXIS_RZ</td>
3068 </tr>
3069</table>
3070
3071
3072<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3073
3074<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3075
3076
3077<p>Android Television device implementations SHOULD provide a remote control to
3078allow users to access the TV interface. The remote control MAY be a physical
3079remote or can be a software-based remote that is accessible from a mobile phone
3080or tablet. The remote control MUST meet the requirements defined below.</p>
3081
3082<ul>
3083 <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>
3084 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3085support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3086</ul>
3087
3088<h2 id="7_3_sensors">7.3. Sensors</h2>
3089
3090
3091<p>Android includes APIs for accessing a variety of sensor types. Devices
3092implementations generally MAY omit these sensors, as provided for in the
3093following subsections. If a device includes a particular sensor type that has a
3094corresponding API for third-party developers, the device implementation MUST
3095implement that API as described in the Android SDK documentation and the
3096Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3097
3098<ul>
3099 <li>MUST accurately report the presence or absence of sensors per the
3100android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3101 <li>MUST return an accurate list of supported sensors via the
3102SensorManager.getSensorList() and similar methods.</li>
3103 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3104true or false as appropriate when applications attempt to register listeners,
3105not calling sensor listeners when the corresponding sensors are not present;
3106etc.).</li>
3107 <li>MUST report all sensor measurements using the relevant International System of
3108Units (metric) values for each sensor type as defined in the Android SDK
3109documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3110 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3111documentation, representing the time the event happened and synchronized with
3112the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3113are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3114platform releases where this might become a REQUIRED component. The
3115synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3116</ul>
3117
3118<p>The list above is not comprehensive; the documented behavior of the Android SDK
3119and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3120
3121<p>Some sensor types are composite, meaning they can be derived from data provided
3122by one or more other sensors. (Examples include the orientation sensor, and the
3123linear acceleration sensor.) Device implementations SHOULD implement these
3124sensor types, when they include the prerequisite physical sensors as described
3125in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3126If a device implementation includes a composite sensor it MUST implement the
3127sensor as described in the Android Open Source documentation on composite
3128sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3129
3130<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3131continuously [<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
3132sensor, device implementations MUST continuously provide periodic data samples
3133that SHOULD have a jitter below 3%, where jitter is defined as the standard
3134deviation of the difference of the reported timestamp values between
3135consecutive events.</p>
3136
3137<p>Note that the device implementations MUST ensure that the sensor event stream
3138MUST NOT prevent the device CPU from entering a suspend state or waking up from
3139a suspend state.</p>
3140
3141<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3142exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3143
3144<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3145
3146
3147<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3148devices and Android Watch devices are strongly encouraged to include this
3149sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3150
3151<ul>
3152 <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>
3153 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3154 Android Watch devices as such devices have a stricter power constraint and
3155 100 Hz for all other device types.</li>
3156 <li>SHOULD report events up to at least 200 Hz.</li>
3157 <li>MUST comply with the Android sensor coordinate system as detailed in the
3158Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3159 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3160more on any axis.</li>
3161 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3162least 16-bits.</li>
3163 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3164cycle and compensated, and preserve the compensation parameters between device
3165reboots.</li>
3166 <li>SHOULD be temperature compensated.</li>
3167 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3168deviation should be calculated on a per axis basis on samples collected over a
3169period of at least 3 seconds at the fastest sampling rate.</li>
3170 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3171TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3172Android 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
3173sensors are implemented, the sum of their power consumption MUST always be less
3174than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3175dynamic or static condition.</li>
3176 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3177TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3178TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3179are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3180 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3181and a magnetometer sensor is also included.</li>
3182</ul>
3183
3184<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3185
3186
3187<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3188device does include a 3-axis magnetometer, it:</p>
3189
3190<ul>
3191 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3192TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3193strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3194 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3195report events up to at least 50 Hz.</li>
3196 <li>MUST comply with the Android sensor coordinate system as detailed in the
3197Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3198 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3199saturating.</li>
3200 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3201below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3202and static (magnet-induced) magnetic fields.</li>
3203 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3204equal or denser than 0.2 &micro;.</li>
3205 <li>SHOULD be temperature compensated.</li>
3206 <li>MUST support online calibration and compensation of the hard iron bias, and
3207preserve the compensation parameters between device reboots.</li>
3208 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3209while in use or during the production of the device.</li>
3210 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3211collected over a period of at least 3 seconds at the fastest sampling rate, no
3212greater than 0.5 &micro;T.</li>
3213 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3214sensor and a gyroscope sensor is also included.</li>
3215 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3216sensor is also implemented. However if implemented, it MUST consume less than
321710 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3218mode at 10 Hz.</li>
3219</ul>
3220
3221<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3222
3223
3224<p>Device implementations SHOULD include a GPS receiver. If a device
3225implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3226
3227<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3228
3229
3230<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3231Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3232also included. If a device implementation includes a gyroscope, it:</p>
3233
3234<ul>
3235 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3236TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3237strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3238 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3239 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3240 Android Watch devices as such devices have a stricter power constraint and
3241 100 Hz for all other device types.</li>
3242 <li>SHOULD report events up to at least 200 Hz.</li>
3243 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
324416-bits or more.</li>
3245 <li>MUST be temperature compensated.</li>
3246 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3247parameters between device reboots.</li>
3248 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3249or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3250be constrained by this value. In other words, if you measure the variance of
3251the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3252 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3253sensor and a magnetometer sensor is also included.</li>
3254 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3255TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3256TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3257are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3258</ul>
3259
3260<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3261
3262
3263<p>Device implementations SHOULD include a barometer (ambient air pressure
3264sensor). If a device implementation includes a barometer, it:</p>
3265
3266<ul>
3267 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3268 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3269 <li>MUST have adequate precision to enable estimating altitude.</li>
3270 <li>MUST be temperature compensated.</li>
3271</ul>
3272
3273<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3274
3275
3276<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3277If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3278measure the ambient (room) temperature in degrees Celsius.</p>
3279
3280<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3281present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3282temperature of the device CPU, and it MUST NOT measure any other temperature.
3283Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3284
3285<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3286
3287
3288<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3289
3290<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3291
3292
3293<p>Device implementations MAY include a proximity sensor. Devices that can make a
3294voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3295SHOULD include a proximity sensor. If a device implementation does include a
3296proximity sensor, it:</p>
3297
3298<ul>
3299 <li>MUST measure the proximity of an object in the same direction as the screen.
3300That is, the proximity sensor MUST be oriented to detect objects close to the
3301screen, as the primary intent of this sensor type is to detect a phone in use
3302by the user. If a device implementation includes a proximity sensor with any
3303other orientation, it MUST NOT be accessible through this API.</li>
3304 <li>MUST have 1-bit of accuracy or more.</li>
3305</ul>
3306
3307<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3308
3309
3310<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3311
3312
3313<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3314to hardware related to placing voice calls and sending SMS messages via a GSM
3315or CDMA network. While these voice calls may or may not be packet-switched,
3316they are for the purposes of Android considered independent of any data
3317connectivity that may be implemented using the same network. In other words,
3318the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3319calls and SMS. For instance, device implementations that cannot place calls or
3320send/receive SMS messages MUST NOT report the android.hardware.telephony
3321feature or any subfeatures, regardless of whether they use a cellular network
3322for data connectivity.</p>
3323
3324<p>Android MAY be used on devices that do not include telephony hardware. That is,
3325Android is compatible with devices that are not phones. However, if a device
3326implementation does include GSM or CDMA telephony, it MUST implement full
3327support for the API for that technology. Device implementations that do not
3328include telephony hardware MUST implement the full APIs as no-ops.</p>
3329
3330<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3331
3332<div class="note">
3333<p>Android Television device implementations MUST include Wi-Fi support.</p>
3334</div>
3335
3336
3337<p>Android Television device implementations MUST include support for one or more
3338forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3339implementation SHOULD include support for one or more forms of 802.11. If a
3340device implementation does include support for 802.11 and exposes the
3341functionality to a third-party application, it MUST implement the corresponding
3342Android API and:</p>
3343
3344<ul>
3345 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3346 <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>
3347 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3348(224.0.0.251) at any time of operation including when the screen is not in an
3349active state.</li>
3350</ul>
3351
3352<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3353
3354
3355<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3356peer-to-peer). If a device implementation does include support for Wi-Fi
3357Direct, it MUST implement the corresponding Android API as described in the SDK
3358documentation [<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>
3359
3360<ul>
3361 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3362 <li>MUST support regular Wi-Fi operation.</li>
3363 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3364</ul>
3365
3366<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3367
3368<div class="note">
3369<p>Android Television device implementations MUST include support for Wi-Fi
3370Tunneled Direct Link Setup (TDLS).</p>
3371</div>
3372
3373
3374<p>Android Television device implementations MUST include support for Wi-Fi
3375Tunneled Direct Link Setup (TDLS) and other types of Android device
3376implementations SHOULD include support for Wi-Fi TDLS as described in the
3377Android 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
3378by the WiFiManager API, the device:</p>
3379
3380<ul>
3381 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3382 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3383than going through the Wi-Fi access point.</li>
3384</ul>
3385
3386<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3387
3388<div class="note">
3389<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3390Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3391</div>
3392
3393
3394<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
3395Energy MUST declare the relevant platform features (android.hardware.bluetooth
3396and android.hardware.bluetooth_le respectively) and implement the platform
3397APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3398as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3399device implementations MUST support Bluetooth and Bluetooth LE. </p>
3400
3401<p>Device implementations including support for Bluetooth Low Energy:</p>
3402
3403<ul>
3404 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3405 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3406described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3407 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3408implementing 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
3409android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3410 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3411if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3412android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3413 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3414MUST report &lsquo;false&rsquo; whenever queried via the
3415android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3416</ul>
3417
3418<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3419
3420
3421<p>Device implementations SHOULD include a transceiver and related hardware for
3422Near-Field Communications (NFC). If a device implementation does include NFC
3423hardware and plans to make it available to third-party apps, then it:</p>
3424
3425<ul>
3426 <li>MUST report the android.hardware.nfc feature from the
3427android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3428 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3429standards:
3430 <ul>
3431 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3432Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3433following NFC standards:
3434 <ul>
3435 <li>NfcA (ISO14443-3A)</li>
3436 <li>NfcB (ISO14443-3B)</li>
3437 <li>NfcF (JIS 6319-4)</li>
3438 <li>IsoDep (ISO 14443-4)</li>
3439 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3440 </ul>
3441 <li>SHOULD be capable of reading and writing NDEF messages via the following NFC
3442standards. Note that while the NFC standards below are stated as SHOULD, the
3443Compatibility Definition for a future version is planned to change these to
3444MUST. These standards are optional in this version but will be required in
3445future 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>
3446 <ul>
3447 <li>NfcV (ISO 15693)</li>
3448 </ul></li>
3449 <li>MUST be capable of transmitting and receiving data via the following
3450peer-to-peer standards and protocols:
3451 <ul>
3452 <li>ISO 18092</li>
3453 <li>LLCP 1.0 (defined by the NFC Forum)</li>
3454 <li>SDP 1.0 (defined by the NFC Forum)</li>
3455 <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>
3456 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3457 </ul></li>
3458 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3459 <ul>
3460 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3461default SNEP server MUST be dispatched to applications using the
3462android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3463MUST NOT disable dispatch of incoming NDEF message.</li>
3464 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3465settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3466 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3467processed the same way as the SNEP default server.</li>
3468 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3469default SNEP server when Android Beam is enabled. If no default SNEP server is
3470found then the client MUST attempt to send to an NPP server.</li>
3471 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3472android.nfc.NfcAdapter.setNdefPushMessage, and
3473android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3474android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3475 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3476sending outbound P2P NDEF messages.</li>
3477 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3478using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3479 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3480Bluetooth Object Push Profile. Device implementations MUST support connection
3481handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3482implementing 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
3483LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3484handover request/select records over NFC, and it MUST use the Bluetooth Object
3485Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3486remain compatible with Android 4.1 devices), the implementation SHOULD still
3487accept SNEP GET requests for exchanging the handover request/select records
3488over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3489for performing connection handover.</li>
3490 </ul></li>
3491 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3492 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3493active and the lock-screen unlocked.</li>
3494</ul>
3495</ul>
3496
3497<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3498Forum specifications cited above.)</p>
3499
3500<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3501device implementation does include an NFC controller chipset capable of HCE and
3502Application ID (AID) routing, then it:</p>
3503
3504<ul>
3505 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3506 <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>
3507</ul>
3508
3509<p>Additionally, device implementations MAY include reader/writer support for the
3510following MIFARE technologies.</p>
3511
3512<ul>
3513 <li>MIFARE Classic</li>
3514 <li>MIFARE Ultralight</li>
3515 <li>NDEF on MIFARE Classic</li>
3516</ul>
3517
3518<p>Note that Android includes APIs for these MIFARE types. If a device
3519implementation supports MIFARE in the reader/writer role, it:</p>
3520
3521<ul>
3522 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3523 <li>MUST report the feature com.nxp.mifare from the
3524android.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
3525as a constant on the PackageManager class.</li>
3526 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3527feature unless it also implements general NFC support as described in this
3528section.</li>
3529</ul>
3530
3531<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3532the android.hardware.nfc feature from the
3533android.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>
3534
3535<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3536protocol-independent data representation format, device implementations MUST
3537implement these APIs even if they do not include support for NFC or declare the
3538android.hardware.nfc feature.</p>
3539
3540<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3541
3542
3543<p>Device implementations MUST include support for one or more forms of data
3544networking. Specifically, device implementations MUST include support for at
3545least one data standard capable of 200Kbit/sec or greater. Examples of
3546technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3547Ethernet, Bluetooth PAN, etc.</p>
3548
3549<p>Device implementations where a physical networking standard (such as Ethernet)
3550is the primary data connection SHOULD also include support for at least one
3551common wireless data standard, such as 802.11 (Wi-Fi).</p>
3552
3553<p>Devices MAY implement more than one form of data connectivity.</p>
3554
3555<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3556
3557
3558<p>Device implementations MUST have the master auto-sync setting on by default so
3559that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3560
3561<h2 id="7_5_cameras">7.5. Cameras</h2>
3562
3563
3564<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3565front-facing camera. A rear-facing camera is a camera located on the side of
3566the device opposite the display; that is, it images scenes on the far side of
3567the device, like a traditional camera. A front-facing camera is a camera
3568located on the same side of the device as the display; that is, a camera
3569typically used to image the user, such as for video conferencing and similar
3570applications.</p>
3571
3572<p>If a device implementation includes at least one camera, it SHOULD be possible
3573for an application to simultaneously allocate 3 bitmaps equal to the size of
3574the images produced by the largest-resolution camera sensor on the device.</p>
3575
3576<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3577
3578
3579<p>Device implementations SHOULD include a rear-facing camera. If a device
3580implementation includes at least one rear-facing camera, it:</p>
3581
3582<ul>
3583 <li>MUST report the feature flag android.hardware.camera and
3584android.hardware.camera.any.</li>
3585 <li>MUST have a resolution of at least 2 megapixels.</li>
3586 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3587the camera driver (transparent to application software).</li>
3588 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3589 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3590lit while an android.hardware.Camera.PreviewCallback instance has been
3591registered on a Camera preview surface, unless the application has explicitly
3592enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3593of a Camera.Parameters object. Note that this constraint does not apply to the
3594device&rsquo;s built-in system camera application, but only to third-party
3595applications using Camera.PreviewCallback.</li>
3596</ul>
3597
3598<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3599
3600
3601<p>Device implementations MAY include a front-facing camera. If a device
3602implementation includes at least one front-facing camera, it:</p>
3603
3604<ul>
3605 <li>MUST report the feature flag android.hardware.camera.any and
3606android.hardware.camera.front.</li>
3607 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3608 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3609camera API in Android has specific support for front-facing cameras and device
3610implementations MUST NOT configure the API to to treat a front-facing camera as
3611the default rear-facing camera, even if it is the only camera on the device.</li>
3612 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3613cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3614 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3615CameraPreview, as follows:
3616 <ul>
3617 <li>If the device implementation is capable of being rotated by user (such as
3618automatically via an accelerometer or manually via user input), the camera
3619preview MUST be mirrored horizontally relative to the device&rsquo;s current
3620orientation.</li>
3621 <li>If the current application has explicitly requested that the Camera display be
3622rotated 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
3623orientation specified by the application.</li>
3624 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3625axis.</li>
3626 </ul></li>
3627 <li>MUST mirror the image displayed by the postview in the same manner as the
3628camera preview image stream. If the device implementation does not support
3629postview, this requirement obviously does not apply.</li>
3630 <li>MUST NOT mirror the final captured still image or video streams returned to
3631application callbacks or committed to media storage.</li>
3632</ul>
3633
3634<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3635
3636
3637<p>Device implementations with USB host mode MAY include support for an external
3638camera that connects to the USB port. If a device includes support for an
3639external camera, it:</p>
3640
3641<ul>
3642 <li>MUST declare the platform feature android.hardware.camera.external and
3643android.hardware camera.any.</li>
3644 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3645 <li>MAY support multiple cameras.</li>
3646</ul>
3647
3648<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3649high-quality unencoded streams (i.e. raw or independently compressed picture
3650streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3651unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3652device implementation.</p>
3653
3654<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3655
3656
3657<p>Android includes two API packages to access the camera, the newer
3658android.hardware.camera2 API expose lower-level camera control to the app,
3659including efficient zero-copy burst/streaming flows and per-frame controls of
3660exposure, gain, white balance gains, color conversion, denoising, sharpening,
3661and more.</p>
3662
3663<p>The older API package, android.hardware.Camera, is marked as deprecated in
3664Android 5.0 but as it should still be available for apps to use Android device
3665implementations MUST ensure the continued support of the API as described in
3666this section and in the Android SDK.</p>
3667
3668<p>Device implementations MUST implement the following behaviors for the
3669camera-related APIs, for all available cameras:</p>
3670
3671<ul>
3672 <li>If an application has never called
3673android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3674use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3675application callbacks.</li>
3676 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3677and the system calls the onPreviewFrame() method when the preview format is
3678YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3679be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3680 <li>For android.hardware.Camera, device implementations MUST support the YV12
3681format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3682camera previews for both front- and rear-facing cameras. (The hardware video
3683encoder and camera may use any native pixel format, but the device
3684implementation MUST support conversion to YV12.)</li>
3685 <li>For android.hardware.camera2, device implementations must support the
3686android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3687formats as outputs through the android.media.ImageReader API.</li>
3688</ul>
3689
3690<p>Device implementations MUST still implement the full Camera API included in the
3691Android 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
3692capabilities. For instance, cameras that lack autofocus MUST still call any
3693registered android.hardware.Camera.AutoFocusCallback instances (even though
3694this has no relevance to a non-autofocus camera.) Note that this does apply to
3695front-facing cameras; for instance, even though most front-facing cameras do
3696not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3697
3698<p>Device implementations MUST recognize and honor each parameter name defined as
3699a constant on the android.hardware.Camera.Parameters class, if the underlying
3700hardware supports the feature. If the device hardware does not support a
3701feature, the API must behave as documented. Conversely, device implementations
3702MUST NOT honor or recognize string constants passed to the
3703android.hardware.Camera.setParameters() method other than those documented as
3704constants on the android.hardware.Camera.Parameters. That is, device
3705implementations MUST support all standard Camera parameters if the hardware
3706allows, and MUST NOT support custom Camera parameter types. For instance,
3707device implementations that support image capture using high dynamic range
3708(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>
3709
3710<p>Because not all device implementations can fully support all the features of
3711the android.hardware.camera2 API, device implementations MUST report the proper
3712level of support with the android.info.supportedHardwareLevel property as
3713described 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>
3714
3715<p>Device implementations MUST also declare its Individual camera capabilities of
3716android.hardware.camera2 via the android.request.availableCapabilities property
3717and 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>
3718
3719<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3720whenever a new picture is taken by the camera and the entry of the picture has
3721been added to the media store.</p>
3722
3723<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3724whenever a new video is recorded by the camera and the entry of the picture has
3725been added to the media store.</p>
3726
3727<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3728
3729
3730<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3731long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3732when the device is held in the landscape orientation, cameras MUST capture
3733images in the landscape orientation. This applies regardless of the device&rsquo;s
3734natural orientation; that is, it applies to landscape-primary devices as well
3735as portrait-primary devices.</p>
3736
3737<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3738
3739
3740<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3741
3742<div class="note">
3743<p>Android Television devices MUST have at least 5GB of non-volatile storage
3744available for application private data.</p>
3745</div>
3746
3747
3748<p>The memory available to the kernel and userspace on device implementations MUST
3749be at least equal or larger than the minimum values specified by the following
3750table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3751<table>
3752 <tr>
3753 <th>Density and screen size</th>
3754 <th>32-bit device</th>
3755 <th>64-bit device</th>
3756 </tr>
3757 <tr>
3758 <td>Android Watch devices (due to smaller screens)</td>
3759 <td>416MB</td>
3760 <td>Not applicable</td>
3761 </tr>
3762 <tr>
3763 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3764 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3765 <li class="table_list">mdpi or lower on large screens</li>
3766 <li class="table_list">ldpi or lower on extra large screens</li>
3767 </ul></td>
3768 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3769 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3770 </tr>
3771 <tr>
3772 <td><ul>
3773 <li class="table_list">xhdpi or higher on small/normal screens</li>
3774 <li class="table_list">hdpi or higher on large screens</li>
3775 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3776 <td>512MB</td>
3777 <td>832MB</td>
3778 </tr>
3779 <tr>
3780 <td><ul>
3781 <li class="table_list">400dpi or higher on small/normal screens</li>
3782 <li class="table_list">xhdpi or higher on large screens</li>
3783 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3784 <td>896MB</td>
3785 <td>1280MB</td>
3786 </tr>
3787 <tr>
3788 <td><ul>
3789 <li class="table_list">560dpi or higher on small/normal screens</li>
3790 <li class="table_list">400dpi or higher on large screens</li>
3791 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3792 <td>1344MB</td>
3793 <td>1824MB</td>
3794 </tr>
3795</table>
3796
3797
3798<p>The minimum memory values MUST be in addition to any memory space already
3799dedicated to hardware components such as radio, video, and so on that is not
3800under the kernel&rsquo;s control.</p>
3801
3802<p>Device implementations with less than 512MB of memory available to the kernel
3803and userspace, unless an Android Watch, MUST return the value "true" for
3804ActivityManager.isLowRamDevice().</p>
3805
3806<p>Android Television devices MUST have at least 5GB and other device
3807implementations MUST have at least 1.5GB of non-volatile storage available for
3808application private data. That is, the /data partition MUST be at least 5GB for
3809Android Television devices and at least 1.5GB for other device implementations.
3810Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3811they will be able to upgrade to the future platform releases.</p>
3812
3813<p>The Android APIs include a Download Manager that applications MAY use to
3814download 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
3815downloading individual files of at least 100MB in size to the default &ldquo;cache"
3816location.</p>
3817
3818<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3819
3820
3821<p>Device implementations MUST offer shared storage for applications also often
3822referred as &ldquo;shared external storage&rdquo;. </p>
3823
3824<p>Device implementations MUST be configured with shared storage mounted by
3825default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3826path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3827to the actual mount point.</p>
3828
3829<p>Device implementations MAY have hardware for user-accessible removable storage,
3830such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3831shared storage requirement, the device implementation:</p>
3832
3833<ul>
3834 <li>MUST implement a toast or pop-up user interface warning the user when there is
3835no SD card.</li>
3836 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3837and other material available at time of purchase that the SD card has to be
3838separately purchased.</li>
3839 <li>MUST mount the SD card by default.</li>
3840</ul>
3841
3842<p>Alternatively, device implementations MAY allocate internal (non-removable)
3843storage as shared storage for apps as included in the upstream Android Open
3844Source Project; device implementations SHOULD use this configuration and
3845software implementation. If a device implementation uses internal
3846(non-removable) storage to satisfy the shared storage requirement, that storage
3847MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3848symbolic link to the physical location if it is mounted elsewhere).</p>
3849
3850<p>Device implementations MUST enforce as documented the
3851android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3852Shared storage MUST otherwise be writable by any application that obtains that
3853permission.</p>
3854
3855<p>Device implementations that include multiple shared storage paths (such as both
3856an SD card slot and shared internal storage) MUST NOT allow Android
3857applications to write to the secondary external storage, except for their
3858package-specific directories on the secondary external storage, but SHOULD
3859expose content from both storage paths transparently through Android&rsquo;s media
3860scanner service and android.provider.MediaStore.</p>
3861
3862<p>Regardless of the form of shared storage used, if the device implementation
3863has a USB port with USB peripheral mode support, it MUST provide some mechanism
3864to access the contents of shared storage from a host computer. Device
3865implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3866to satisfy this requirement. If the device implementation supports Media
3867Transfer Protocol, it:</p>
3868
3869<ul>
3870 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3871[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3872 <li>SHOULD report a USB device class of 0x00.</li>
3873 <li>SHOULD report a USB interface name of 'MTP'.</li>
3874</ul>
3875
3876<h2 id="7_7_usb">7.7. USB</h2>
3877
3878
3879<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3880USB host mode.</p>
3881
3882<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3883
3884<ul>
3885 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3886-C USB port.</li>
3887 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3888new 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>
3889 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3890SHOULD either locate the port on the bottom of the device (according to natural
3891orientation) or enable software screen rotation for all apps (including home
3892screen), so that the display draws correctly when the device is oriented with
3893the 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>
3894 <li>It MUST allow a USB host connected with the Android device to access the
3895contents of the shared storage volume using either USB mass storage or Media
3896Transfer Protocol.</li>
3897 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3898documented in the Android SDK documentation, and if it is an Android Handheld
3899device it MUST implement the AOA API. Device implementations implementing the
3900AOA specification:
3901 <ul>
3902 <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>
3903 <li>MUST implement the USB audio class as documented in the Android SDK
3904documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3905 </ul></li>
3906 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3907as 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>
3908 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3909the value of android.os.Build.SERIAL.</li>
3910</ul>
3911
3912<p>If a device implementation includes a USB port supporting host mode, it:</p>
3913
3914<ul>
3915 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3916 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3917cables adapting the port to a standard type-A or type-C USB port.</li>
3918 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3919adapting the port to a standard type-A or type-C USB port.</li>
3920 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3921documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3922 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3923MUST 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>
3924 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3925as 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>
3926</ul>
3927
3928<h2 id="7_8_audio">7.8. Audio</h2>
3929
3930
3931<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3932
3933<div class="note">
3934<p>Android Handheld, Watch, and Automotive implementations MUST include a
3935microphone.</p>
3936</div>
3937
3938
3939<p>Device implementations MAY omit a microphone. However, if a device
3940implementation omits a microphone, it MUST NOT report the
3941android.hardware.microphone feature constant, and MUST implement the audio
3942recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
3943
3944<ul>
3945 <li>MUST report the android.hardware.microphone feature constant
3946 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
3947 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
3948</ul>
3949
3950<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
3951
3952<div class="note">
3953<p>Android Watch devices MAY include an audio output.</p>
3954</div>
3955
3956<p>Device implementations including a speaker or with an audio/multimedia output
3957port for an audio output peripheral as a headset or an external speaker:</p>
3958
3959<ul>
3960 <li>MUST report the android.hardware.audio.output feature constant.</li>
3961 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
3962 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
3963</ul>
3964
3965<p>Conversely, if a device implementation does not include a speaker or audio
3966output port, it MUST NOT report the android.hardware.audio output feature, and
3967MUST implement the Audio Output related APIs as no-ops at least. </p>
3968
3969<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
3970other types of Android device implementations MUST have an audio output and
3971declare android.hardware.audio.output.</p>
3972
3973<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
3974
3975
3976<p>In order to be compatible with the headsets and other audio accessories using
3977the 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
3978one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
3979implementation has a 4 conductor 3.5mm audio jack, it:</p>
3980
3981<ul>
3982 <li>MUST support audio playback to stereo headphones and stereo headsets with a
3983microphone, and SHOULD support audio recording from stereo headsets with a
3984microphone.</li>
3985 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
3986audio plugs with the OMTP pin-out order.</li>
3987 <li>MUST support the detection of microphone on the plugged in audio accessory, if
3988the device implementation supports a microphone, and broadcast the
3989android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
3990 <li>SHOULD support the detection and mapping to the keycodes for the following 3
3991ranges of equivalent impedance between the microphone and ground conductors on
3992the audio plug:
3993 <ul>
3994 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
3995 <li><strong>210&#45;290 Ohm</strong>:<strong> </strong>KEYCODE_VOLUME_UP</li>
3996 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
3997 </ul></li>
3998 <li>SHOULD support the detection and mapping to the keycode for the following range
3999of equivalent impedance between the microphone and ground conductors on the
4000audio plug:
4001 <ul>
4002 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4003 </ul></li>
4004 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4005contacts on plug are touching their relevant segments on the jack.</li>
4006 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4007speaker impedance.</li>
4008 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4009</ul>
4010
4011<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4012
4013
4014<p>Some minimum performance criterias are critical to the user experience and
4015impacts the baseline assumptions developers would have when developing an app.
4016Android Watch devices SHOULD and other type of device implementations MUST meet
4017the following criteria:</p>
4018
4019<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4020
4021
4022<p>Device implementations MUST provide a smooth user interface by ensuring a
4023consistent frame rate and response times for applications and games. Device
4024implementations MUST meet the following requirements: </p>
4025
4026<ul>
4027 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4028often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4029 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4030list of 10K list entries as defined by the Android Compatibility Test Suite
4031(CTS) in less than 36 secs.</li>
4032 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4033application after it has been launched MUST take less than 1 second.</li>
4034</ul>
4035
4036<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4037
4038
4039<p>Device implementations MUST ensure internal storage file access performance consistency for read
4040and write operations. </p>
4041
4042<ul>
4043 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4044for a 256MB file using 10MB write buffer.</li>
4045 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4046256MB file using 4KB write buffer.</li>
4047 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4048a 256MB file using 10MB write buffer.</li>
4049 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4050256MB file using 4KB write buffer.</li>
4051</ul>
4052
4053<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4054
4055
4056<p>Device implementations MUST implement a security model consistent with the
4057Android platform security model as defined in Security and Permissions
4058reference 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
4059installation of self-signed applications without requiring any additional
4060permissions/certificates from any third parties/authorities. Specifically,
4061compatible devices MUST support the security mechanisms described in the follow
4062subsections.</p>
4063
4064<h2 id="9_1_permissions">9.1. Permissions</h2>
4065
4066
4067<p>Device implementations MUST support the Android permissions model as defined in
4068the 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
4069described in the SDK documentation; no permissions may be omitted, altered, or
4070ignored. Implementations MAY add additional permissions, provided the new
4071permission ID strings are not in the android.* namespace.</p>
4072
4073<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4074
4075
4076<p>Device implementations MUST support the Android application sandbox model, in
4077which each application runs as a unique Unixstyle UID and in a separate
4078process. Device implementations MUST support running multiple applications as
4079the same Linux user ID, provided that the applications are properly signed and
4080constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4081
4082<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4083
4084
4085<p>Device implementations MUST support the Android file access permissions model
4086as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4087
4088<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4089
4090
4091<p>Device implementations MAY include runtime environments that execute
4092applications using some other software or technology than the Dalvik Executable
4093Format or native code. However, such alternate execution environments MUST NOT
4094compromise the Android security model or the security of installed Android
4095applications, as described in this section.</p>
4096
4097<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4098standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4099
4100<p>Alternate runtimes MUST NOT be granted access to resources protected by
4101permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4102&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4103
4104<p>Alternate runtimes MUST NOT permit applications to make use of features
4105protected by Android permissions restricted to system applications.</p>
4106
4107<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4108alternate runtimes:</p>
4109
4110<ul>
4111 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4112Linux user IDs, etc.).</li>
4113 <li>MAY provide a single Android sandbox shared by all applications using the
4114alternate runtime.</li>
4115 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4116sandbox of any other app installed on the device, except through the standard
4117Android mechanisms of shared user ID and signing certificate.</li>
4118 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4119corresponding to other Android applications.</li>
4120 <li>MUST NOT be launched with, be granted, or grant to other applications any
4121privileges of the superuser (root), or of any other user ID.</li>
4122</ul>
4123
4124<p>The .apk files of alternate runtimes MAY be included in the system image of a
4125device implementation, but MUST be signed with a key distinct from the key used
4126to sign other applications included with the device implementation.</p>
4127
4128<p>When installing applications, alternate runtimes MUST obtain user consent for
4129the Android permissions used by the application. If an application needs to
4130make use of a device resource for which there is a corresponding Android
4131permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4132user that the application will be able to access that resource. If the runtime
4133environment does not record application capabilities in this manner, the
4134runtime environment MUST list all permissions held by the runtime itself when
4135installing any application using that runtime.</p>
4136
4137<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4138
4139<div class="note">
4140<p>This feature is optional for all device types.</p>
4141</div>
4142
4143
4144<p>Android includes support for multiple users and provides support for full user
4145isolation [<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
4146the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4147
4148<ul>
4149 <li>Device implementations that do not declare the android.hardware.telephony
4150feature flag MUST support restricted profiles, a feature that allows device
4151owners to manage additional users and their capabilities on the device. With
4152restricted profiles, device owners can quickly set up separate environments for
4153additional users to work in, with the ability to manage finer-grained
4154restrictions in the apps that are available in those environments.</li>
4155 <li>Conversely device implementations that declare the android.hardware.telephony
4156feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4157implementation of controls to enable /disable other users from accessing the
4158voice calls and SMS.</li>
4159 <li>Device implementations MUST, for each user, implement a security model
4160consistent with the Android platform security model as defined in Security and
4161Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4162 <li>Device implementations MAY support creating users and managed profiles via the
4163android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4164platform feature flag android.software.managed_users.
4165 <li>Device implementations that declare the feature flag
4166android.software.managed_users MUST use the upstream AOSP icon badge to
4167represent the managed applications and other badge UI elements like Recents &
4168Notifications.</li>
4169 <li>Each user instance on an Android device MUST have separate and isolated
4170external storage directories. Device implementations MAY store multiple users'
4171data on the same volume or filesystem. However, the device implementation MUST
4172ensure that applications owned by and running on behalf a given user cannot
4173list, read, or write to data owned by any other user. Note that removable
4174media, such as SD card slots, can allow one user to access another&rsquo;s data by
4175means of a host PC. For this reason, device implementations that use removable
4176media for the external storage APIs MUST encrypt the contents of the SD card if
4177multiuser is enabled using a key stored only on non-removable media accessible
4178only to the system. As this will make the media unreadable by a host PC, device
4179implementations will be required to switch to MTP or a similar system to
4180provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4181implementations MAY but SHOULD NOT enable multi-user if they use removable
4182media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4183</ul>
4184
4185<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4186
4187
4188<p>Android includes support for warning users of any outgoing premium SMS message
4189[<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
4190carrier that may incur a charge to the user. Device implementations that
4191declare support for android.hardware.telephony MUST warn users before sending a
4192SMS message to numbers identified by regular expressions defined in
4193/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4194Project provides an implementation that satisfies this requirement.</p>
4195
4196<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4197
4198
4199<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4200(SELinux) mandatory access control (MAC) system and other security features in
4201the Linux kernel. SELinux or any other security features, if implemented below
4202the Android framework:</p>
4203
4204<ul>
4205 <li>MUST maintain compatibility with existing applications.</li>
4206 <li>MUST NOT have a visible user interface when a security violation is detected
4207and successfully blocked, but MAY have a visible user interface when an
4208unblocked security violation occurs resulting in a successful exploit.</li>
4209 <li>SHOULD NOT be user or developer configurable.</li>
4210</ul>
4211
4212<p>If any API for configuration of policy is exposed to an application that can
4213affect another application (such as a Device Administration API), the API MUST
4214NOT allow configurations that break compatibility.</p>
4215
4216<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4217if using a kernel other than Linux and meet the following requirements, which
4218are satisfied by the reference implementation in the upstream Android Open
4219Source Project.</p>
4220
4221<p>Device implementations:</p>
4222
4223<ul>
4224 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4225per-domain basis, and MUST configure all domains in enforcing mode. No
4226permissive mode domains are allowed, including domains specific to a
4227device/vendor.</li>
4228 <li>SHOULD load policy from /sepolicy file on the device.</li>
4229 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4230sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4231the policy MUST compile with all neverallow present, for both AOSP SELinux
4232domains as well as device/vendor specific domains.</li>
4233 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4234system image update.</li>
4235</ul>
4236
4237<p>Device implementations SHOULD retain the default SELinux policy provided in the
4238upstream Android Open Source Project, until they have first audited their
4239additions to the SELinux policy. Device implementations MUST be compatible with
4240the upstream Android Open Source Project.</p>
4241
4242<h2 id="9_8_privacy">9.8. Privacy</h2>
4243
4244<p>If the device implements functionality in the system that captures the contents
4245displayed on the screen and/or records the audio stream played on the device,
4246it MUST continuously notify the user whenever this functionality is enabled and
4247actively capturing/recording.</p>
4248
4249<p>If a device implementation has a mechanism that routes network data traffic
4250through a proxy server or VPN gateway by default (for example, preloading a VPN
4251service with android.permission.CONTROL_VPN granted), the device implementation
4252MUST ask for the user's consent before enabling that mechanism.</p>
4253
4254<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4255
4256<div class="note">
4257<p>Optional for Android device implementations without a lock screen.</p>
4258</div>
4259
4260
4261<p>If the device implementation supports a lock screen with PIN (numeric) or
4262PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4263application private data (/data partition), as well
4264as the SD card partition if it is a permanent, non-removable part of the device
4265[<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
4266be enabled all the time after the user has completed the out-of-box experience.
4267While this requirement is stated as SHOULD for this version of the Android
4268platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4269Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4270for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4271be written to storage at any time without being encrypted. Other than when in
4272active use, the encryption key SHOULD be AES encrypted with the lockscreen
4273passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4274If the user has not specified a lockscreen passcode or has disabled use of the
4275passcode for encryption, the system SHOULD use a default passcode to wrap the
4276encryption key. If the device provides a hardware-backed keystore, the password
4277stretching algorithm MUST be cryptographically bound to that keystore. The
4278encryption key MUST NOT be sent off the device (even when wrapped with the user
4279passcode and/or hardware bound key). The upstream Android Open Source project
4280provides a preferred implementation of this feature based on the linux kernel
4281feature dm-crypt.</p>
4282
4283<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4284
4285<p>
4286Verified boot is a feature that guarantees the integrity of the device software.
4287If a device implementation supports the feature, it MUST:
4288<ul>
4289<li>Declare the platform feature flag android.software.verified_boot</li>
4290<li>Perform verification on every boot sequence</li>
4291<li>Start verification from a hardware key that is the root of trust, and go
4292all the way up to the system partition</li>
4293<li>Implement each stage of verification to check the integrity and authenticity
4294of all the bytes in the next stage before executing the code in the next stage</li>
4295<li>Use verification algorithms as strong as current recommendations
4296from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4297</ul>
4298</p>
4299
4300<p>Device implementations SHOULD support verified boot for device integrity.
4301While this requirement is SHOULD for this version of the Android platform,
4302it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4303in future versions of Android. The upstream Android Open Source Project provides
4304a preferred implementation of this feature based on the linux kernel feature dm-verity.
4305</p>
4306
4307<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4308
4309
4310<p>Device implementations MUST pass all tests described in this section.</p>
4311
4312<p>However, note that no software test package is fully comprehensive. For this
4313reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4314preferred implementation of Android available from the Android Open Source
4315Project. This will minimize the risk of introducing bugs that create
4316incompatibilities requiring rework and potential device updates.</p>
4317
4318<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4319
4320
4321<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
4322software on the device. Additionally, device implementers SHOULD use the
4323reference implementation in the Android Open Source tree as much as possible,
4324and MUST ensure compatibility in cases of ambiguity in CTS and for any
4325reimplementations of parts of the reference source code.</p>
4326
4327<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4328may itself contain bugs. The CTS will be versioned independently of this
4329Compatibility Definition, and multiple revisions of the CTS may be released for
4330Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4331at the time the device software is completed.</p>
4332
4333<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4334
4335
4336<p>Device implementations MUST correctly execute all applicable cases in the CTS
4337Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4338is intended to be run by a human operator to test functionality that cannot be
4339tested by an automated system, such as correct functioning of a camera and
4340sensors.</p>
4341
4342<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4343that is optional. Device implementations MUST pass all tests for hardware that
4344they possess; for instance, if a device possesses an accelerometer, it MUST
4345correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4346for features noted as optional by this Compatibility Definition Document MAY be
4347skipped or omitted.</p>
4348
4349<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4350above. However, since many builds are very similar, device implementers are not
4351expected to explicitly run the CTS Verifier on builds that differ only in
4352trivial ways. Specifically, device implementations that differ from an
4353implementation that has passed the CTS Verifier only by the set of included
4354locales, branding, etc. MAY omit the CTS Verifier test.</p>
4355
4356<h1 id="11_updatable_software">11. Updatable Software</h1>
4357
4358
4359<p>Device implementations MUST include a mechanism to replace the entirety of the
4360system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4361device restart MAY be required.</p>
4362
4363<p>Any method can be used, provided that it can replace the entirety of the
4364software preinstalled on the device. For instance, any of the following
4365approaches will satisfy this requirement:</p>
4366
4367<ul>
4368 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4369 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4370 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4371</ul>
4372
4373<p>However, if the device implementation includes support for an unmetered data
4374connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4375
4376<ul>
4377<li>Android Automotive implementations SHOULD support OTA downloads with offline
4378update via reboot.</li>
4379<li>All other device implementations MUST support OTA downloads with offline
4380update via reboot.</li>
4381</ul>
4382
4383<p>The update mechanism used MUST support updates without wiping user data. That
4384is, the update mechanism MUST preserve application private data and application
4385shared data. Note that the upstream Android software includes an update
4386mechanism that satisfies this requirement.</p>
4387
4388<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4389update mechanism SHOULD support verifying that the system image is binary
4390identical to expected result following an OTA. The block-based OTA
4391implementation in the upstream Android Open Source Project, added since Android
43925.1, satisfies this requirement.</p>
4393
4394<p>If an error is found in a device implementation after it has been released but
4395within its reasonable product lifetime that is determined in consultation with
4396the Android Compatibility Team to affect the compatibility of third-party
4397applications, the device implementer MUST correct the error via a software
4398update available that can be applied per the mechanism just described.</p>
4399
4400<h1 id="12_document_changelog">12. Document Changelog</h1>
4401
4402
4403<p>The following table contains a summary of the changes to the Compatibility
4404Definition in this release. </p>
4405<table>
4406 <tr>
4407 <th>Section</th>
4408 <th>Summary of change</th>
4409 </tr>
4410 <tr>
4411 <td>2. Device Types</td>
4412 <td>Added definition for Android automotive implementation.</td>
4413 </tr>
4414 <tr>
4415 <td>2.1 Device Configurations</td>
4416 <td>Added column for Android automotive implementation.</td>
4417 </tr>
4418 <tr>
4419 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4420 <td>New section added.</td>
4421 </tr>
4422 <tr>
4423 <td>3.4.1. WebView Compatibility</td>
4424 <td>Updated webview user agent string requirement to accomodate upstream
4425 implementation change.</td>
4426 </tr>
4427 <tr>
4428 <td>3.4.2. Browser compatibility</td>
4429 <td>Added Android automotive implementations as another case that MAY omit a
4430 browser application.</td>
4431 </tr>
4432 <tr>
4433 <td>3.7. Runtime Compatibility</td>
4434 <td>Updated required runtime heap size for smaller screens and added requirement
4435 for the new dpi bucket (280dpi).</td>
4436 </tr>
4437 <tr>
4438 <td>3.8.3. Notifications</td>
4439 <td>Clarified notification requirement for Android Watch, Television and
4440 Automotive implementations.</td>
4441 </tr>
4442 <tr>
4443 <td>3.8.10. Lock Screen Media Control<</td>
4444 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4445 </tr>
4446 <tr>
4447 <td>3.8.13. Unicode and font</td>
4448 <td>Relaxed Emoji character input method requirement.</td>
4449 </tr>
4450 <tr>
4451 <td>3.9. Device Administration</td>
4452 <td>Clarified condition when the full range of device administration policies
4453 has to be supported.</td>
4454 </tr>
4455 <tr>
4456 <td>3.10. Accessibility</td>
4457 <td>Added Android automotive requirements.</td>
4458 </tr>
4459 <tr>
4460 <td>3.11. Text-To-Speech</td>
4461 <td>Added Android automotive requirements.</td>
4462 </tr>
4463 <tr>
4464 <td>5.1. Media Codecs</td>
4465 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4466 </tr>
4467 <tr>
4468 <td>5.1.3 Video Codecs</td>
4469 <td>Added Android automotive requirements.</td>
4470 </tr>
4471 <tr>
4472 <td>7.1.1.3. Screen Density</td>
4473 <td>Added a new screen dpi (280dpi).</td>
4474 </tr>
4475 <tr>
4476 <td>7.1.5. Legacy Application Compatibility Mode</td>
4477 <td>Added Android automotive requirements.</td>
4478 </tr>
4479 <tr>
4480 <td>7.2 Input Devices</td>
4481 <td>Added general introduction statement.</td>
4482 </tr>
4483 <tr>
4484 <td>7.2.1. Keyboard</td>
4485 <td>Added Android Automotive requirements.</td>
4486 </tr>
4487 <tr>
4488 <td>7.2.3. Navigation Keys</td>
4489 <td>Added Android Automotive requirements.</td>
4490 </tr>
4491 <tr>
4492 <td>7.3.1. Accelerometer</td>
4493 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4494 </tr>
4495 <tr>
4496 <td>7.3.4. Gyroscope</td>
4497 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4498 </tr>
4499 <tr>
4500 <td>7.4.3 Bluetooth</td>
4501 <td>Added Android Automotive requirements.</td>
4502 </tr>
4503 <tr>
4504 <td>7.4.4. Near-Field Communications</td>
4505 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4506 </tr>
4507 <tr>
4508 <td>7.6.1. Minimum Memory and Storage</td>
4509 <td>Updated minimum memory requirements for lower resulution screen devices
4510 and added hard-limit requirement isLowRamDevice().</td>
4511 </tr>
4512 <tr>
4513 <td>7.6.2. Application Shared Storage</td>
4514 <td>Updated requirements when support for host machine access is mandatory.</td>
4515 </tr>
4516 <tr>
4517 <td>7.8.1. Microphone</td>
4518 <td>Added Android Automotive requirements.</td>
4519 </tr>
4520 <tr>
4521 <td>8.2. File I/O Access Performance</td>
4522 <td>Clarified requirements.</td>
4523 </tr>
4524 <tr>
4525 <td>9.8. Privacy</td>
4526 <td>Added privacy requirement for preloaded VPNs.</td>
4527 </tr>
4528 <tr>
4529 <td>9.9. Full-Disk Encryption</td>
4530 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4531 </tr>
4532 <tr>
4533 <td>9.10. Verified Boot</td>
4534 <td>Clarified definition of verified boot.</td>
4535 </tr>
4536 <tr>
4537 <td>11. Updatable Software</td>
4538 <td>Clarified the OTA download requirement is allowed but not mandatory for
4539 Android Automotive implementations.</td>
4540 </tr>
4541</table>
4542
4543
4544<h1 id="13_contact_us">13. Contact Us</h1>
4545
4546
4547<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
4548does not cover.</p>
4549
4550<h1 id="14_resources">14. Resources</h1>
4551
4552
4553<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4554
4555<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4556
4557<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>
4558
4559<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>
4560
4561<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4562
4563<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>
4564
4565<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>
4566
4567<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>
4568
4569<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>
4570
4571<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>
4572
4573<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>
4574
4575<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>
4576
4577<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4578
4579<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4580
4581<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>
4582
4583<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>
4584
4585<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4586
4587<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4588
4589<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4590
4591<p>20. Dalvik Executable Format and bytecode specification: available in the
4592Android source code, at dalvik/docs</p>
4593
4594<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>
4595
4596<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>
4597
4598<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>
4599
4600<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>
4601
4602<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4603
4604<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>
4605
4606<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>
4607
4608<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>
4609
4610<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>
4611
4612<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>
4613
4614<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>
4615
4616<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>
4617
4618<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>
4619
4620<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>
4621
4622<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>
4623
4624<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>
4625
4626<p>37. Settings.Secure LOCATION_MODE:</p>
4627
4628<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>
4629
4630<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>
4631
4632<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>
4633
4634<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>
4635
4636<p>41. Android Device Owner App:</p>
4637
4638<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>
4639
4640<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>
4641
4642<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>
4643
4644<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4645
4646<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>
4647
4648<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>
4649
4650<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>
4651
4652<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>
4653
4654<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>
4655
4656<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>
4657
4658<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>
4659
4660<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>
4661
4662<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4663
4664<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>
4665
4666<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>
4667
4668<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4669
4670<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4671
4672<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4673
4674<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>
4675
4676<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4677
4678<p>60. Android Application Development-Related Settings:</p>
4679
4680<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>
4681
4682<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>
4683
4684<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>
4685
4686<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4687
4688<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>
4689
4690<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>
4691
4692<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4693
4694<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>
4695
4696<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>
4697
4698<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>
4699
4700<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>
4701
4702<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>
4703
4704<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>
4705
4706<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>
4707
4708<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4709
4710<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>
4711
4712<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>
4713
4714<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>
4715
4716<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>
4717
4718<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>
4719
4720<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>
4721
4722<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>
4723
4724<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>
4725
4726<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>
4727
4728<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>
4729
4730<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>
4731
4732<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>
4733
4734<p>86. Android NFC Sharing Settings:</p>
4735
4736<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>
4737
4738<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>
4739
4740<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>
4741
4742<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>
4743
4744<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>
4745
4746<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>
4747
4748<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>
4749
4750<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>
4751
4752<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>
4753
4754<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>
4755
4756<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4757
4758<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>
4759
4760<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>
4761
4762<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>
4763
4764<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>
4765
4766<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>
4767
4768<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>
4769
4770<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>
4771
4772<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4773
4774<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>
4775
4776<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4777
4778<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>
4779
4780<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4781
4782<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>
4783
4784<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4785
4786<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>
4787
4788<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>
4789
4790<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>
4791
4792<p>Many of these resources are derived directly or indirectly from the Android
4793SDK, and will be functionally identical to the information in that SDK&rsquo;s
4794documentation. In any cases where this Compatibility Definition or the
4795Compatibility Test Suite disagrees with the SDK documentation, the SDK
4796documentation is considered authoritative. Any technical details provided in
4797the references included above are considered by inclusion to be part of this
4798Compatibility Definition.</p>
4799
4800</div>
4801</body>
4802</html>