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2<head>
3<title>Android ANDROID_VERSION Compatibility Definition</title>
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Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]5</head>
6
7<body>
8
9<h6>Table of Contents</h6>
10
11<div id="toc">
12
13<div id="toc_left">
14
15<p class="toc_h1"><a href="#1_introduction">1. Introduction</a></p>
16
17<p class="toc_h1"><a href="#2_device_types">2. Device Types</a></p>
18
19<p class="toc_h2"><a href="#2_1_device_configurations">2.1 Device Configurations</a></p>
20
21<p class="toc_h1"><a href="#3_software">3. Software</a></p>
22
23<p class="toc_h2"><a href="#3_1_managed_api_compatibility">3.1. Managed API Compatibility</a></p>
24
25<p class="toc_h2"><a href="#3_2_soft_api_compatibility">3.2. Soft API Compatibility</a></p>
26
27<p class="toc_h3"><a href="#3_2_1_permissions">3.2.1. Permissions</a></p>
28
29<p class="toc_h3"><a href="#3_2_2_build_parameters">3.2.2. Build Parameters</a></p>
30
31<p class="toc_h3"><a href="#3_2_3_intent_compatibility">3.2.3. Intent Compatibility</a></p>
32
33<p class="toc_h4"><a href="#3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</a></p>
34
35<p class="toc_h4"><a href="#3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</a></p>
36
37<p class="toc_h4"><a href="#3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</a></p>
38
39<p class="toc_h4"><a href="#3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</a></p>
40
41<p class="toc_h4"><a href="#3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</a></p>
42
43<p class="toc_h2"><a href="#3_3_native_api_compatibility">3.3. Native API Compatibility</a></p>
44
45<p class="toc_h3"><a href="#3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</a></p>
46
47<p class="toc_h3"><a href="#3_3_2_32-bit_arm_native_code_compatibility">3.3.2. 32-bit ARM Native Code Compatibility</a></p>
48
49<p class="toc_h2"><a href="#3_4_web_compatibility">3.4. Web Compatibility</a></p>
50
51<p class="toc_h3"><a href="#3_4_1_webview_compatibility">3.4.1. WebView Compatibility</a></p>
52
53<p class="toc_h3"><a href="#3_4_2_browser_compatibility">3.4.2. Browser Compatibility</a></p>
54
55<p class="toc_h2"><a href="#3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</a></p>
56
57<p class="toc_h2"><a href="#3_6_api_namespaces">3.6. API Namespaces</a></p>
58
59<p class="toc_h2"><a href="#3_7_runtime_compatibility">3.7. Runtime Compatibility</a></p>
60
61<p class="toc_h2"><a href="#3_8_user_interface_compatibility">3.8. User Interface Compatibility</a></p>
62
63<p class="toc_h3"><a href="#3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</a></p>
64
65<p class="toc_h3"><a href="#3_8_2_widgets">3.8.2. Widgets</a></p>
66
67<p class="toc_h3"><a href="#3_8_3_notifications">3.8.3. Notifications</a></p>
68
69<p class="toc_h3"><a href="#3_8_4_search">3.8.4. Search</a></p>
70
71<p class="toc_h3"><a href="#3_8_5_toasts">3.8.5. Toasts</a></p>
72
73<p class="toc_h3"><a href="#3_8_6_themes">3.8.6. Themes</a></p>
74
75<p class="toc_h3"><a href="#3_8_7_live_wallpapers">3.8.7. Live Wallpapers</a></p>
76
77<p class="toc_h3"><a href="#3_8_8_activity_switching">3.8.8. Activity Switching</a></p>
78
79<p class="toc_h3"><a href="#3_8_9_input_management">3.8.9. Input Management</a></p>
80
81<p class="toc_h3"><a href="#3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</a></p>
82
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>
Unsuk Jung06706432015-08-31 11:26:13 -0700[diff] [blame^]865 <li>MUST report, via the above parameters, only those ABIs documented and
866described in the latest version of the Android NDK ABI Management documentation
867[<a href="https://developer.android.com/ndk/guides/abis.html">Resources, XX</a>],
868and MUST include support for the Advanced SIMD (a.k.a. NEON)
869[<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">Resources,XX</a>]
870extension
871 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]872 <li>SHOULD be built using the source code and header files available in the
873upstream Android Open Source Project</li>
874</ul>
875
876<p>The following native code APIs MUST be available to apps that include native
877code:</p>
878
879<ul>
880 <li>libc (C library)</li>
881 <li>libm (math library)</li>
882 <li>Minimal support for C++</li>
883 <li>JNI interface</li>
884 <li>liblog (Android logging)</li>
885 <li>libz (Zlib compression)</li>
886 <li>libdl (dynamic linker)</li>
887 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
888 <li>libGLESv2.so (OpenGL ES 2.0)</li>
889 <li>libGLESv3.so (OpenGL ES 3.x)</li>
890 <li>libEGL.so (native OpenGL surface management)</li>
891 <li>libjnigraphics.so</li>
892 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
893 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
894 <li>libandroid.so (native Android activity support)</li>
895 <li>libmediandk.so (native media APIs support)</li>
896 <li>Support for OpenGL, as described below</li>
897</ul>
898
899<p>Note that future releases of the Android NDK may introduce support for
900additional ABIs. If a device implementation is not compatible with an existing
901predefined ABI, it MUST NOT report support for any ABIs at all.</p>
902
903<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
904(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
905Android 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
906symbols must be present, only the corresponding functions for OpenGL ES
907versions and extensions actually supported by the device must be fully
908implemented.</p>
909
910<p>Native code compatibility is challenging. For this reason, device implementers
911are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
912Android Open Source Project. </p>
913
914<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9153.3.2. 32-bit ARM Native Code Compatibility
916</h3>
917
918<p>The ARMv8 architecture deprecates several CPU operations, including some
919operations used in existing native code. On 64-bit ARM devices, the following
920deprecated operations MUST remain available to 32-bit native ARM code, either
921through native CPU support or through software emulation:</p>
922
923<ul>
924<li>SWP and SWPB instructions</li>
925<li>SETEND instruction</li>
926<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
927</ul>
928
929<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
930from 32-bit ARM native code. For compatibility with applications built using this
931NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
932by 32-bit ARM applications:</p>
933
934<ul>
935<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
936supported by the device</li>
937<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
938highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
939</ul>
940
941<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
942applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
943non-ARM applications.</p>
944
945<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
946
947
948<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
949
950<div class="note">
951<p>Android Watch devices MAY, but all other device implementations MUST provide
952a complete implementation of the android.webkit.Webview API.</p>
953</div>
954
955
956<p>The platform feature android.software.webview MUST be reported on any device
957that provides a complete implementation of the android.webkit.WebView API, and
958MUST NOT be reported on devices without a complete implementation of the API.
959The Android Open Source implementation uses code from the Chromium Project to
960implement 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
961rendering system, device implementers MUST use the specific upstream build of
962Chromium in the WebView implementation. Specifically:</p>
963
964<ul>
965 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
966build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
967includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
968 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]969<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]970AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
971Safari/537.36</p>
972 <ul>
973 <li>The value of the $(VERSION) string MUST be the same as the value for
974android.os.Build.VERSION.RELEASE.</li>
975 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
976 note that this is a webview</li>
977 <li>The value of the $(MODEL) string MUST be the same as the value for
978android.os.Build.MODEL.</li>
979 <li>The value of the $(BUILD) string MUST be the same as the value for
980android.os.Build.ID.</li>
981 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
982upstream Android Open Source Project.</li>
983 <li>Device implementations MAY omit Mobile in the user agent string.</li>
984 </ul></li></ul>
985
986<p>The WebView component SHOULD include support for as many HTML5 features as
987possible and if it supports the feature SHOULD conform to the HTML5
988specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
989
990<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
991
992<div class="note">
993<p>Android Television, Watch, and Android Automotive implementations MAY omit a
994browser application, but MUST support the public intent patterns as described in
995<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
996of device implementations MUST include a standalone Browser application for
997general user web browsing.</p>
998</div>
999
1000<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1001However, even if an alternate Browser application is used, the
1002android.webkit.WebView component provided to third-party applications MUST be
1003based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1004
1005<p>Implementations MAY ship a custom user agent string in the standalone Browser
1006application.</p>
1007
1008<p>The standalone Browser application (whether based on the upstream WebKit
1009Browser application or a third-party replacement) SHOULD include support for as
1010much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1011APIs associated with HTML5:</p>
1012
1013<ul>
1014 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1015 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1016 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1017</ul>
1018
1019<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1020[<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
1021IndexedDB over webstorage, IndexedDB is expected to become a required component
1022in a future version of Android.</p>
1023
1024<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1025
1026
1027<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1028consistent with the preferred implementation of the upstream Android Open
1029Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1030
1031<ul>
1032 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1033 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1034type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1035 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1036</ul>
1037
1038<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1039significant portions of the platform for behavioral compatibility, but not all.
1040It is the responsibility of the implementer to ensure behavioral compatibility
1041with the Android Open Source Project. For this reason, device implementers
1042SHOULD use the source code available via the Android Open Source Project where
1043possible, rather than re-implement significant parts of the system.</p>
1044
1045<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1046
1047
1048<p>Android follows the package and class namespace conventions defined by the Java
1049programming language. To ensure compatibility with third-party applications,
1050device implementers MUST NOT make any prohibited modifications (see below) to
1051these package namespaces:</p>
1052
1053<ul>
1054 <li>java.*</li>
1055 <li>javax.*</li>
1056 <li>sun.*</li>
1057 <li>android.*</li>
1058 <li>com.android.*</li>
1059</ul>
1060
1061<p><strong>Prohibited modifications include</strong>:</p>
1062
1063<ul>
1064 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1065platform by changing any method or class signatures, or by removing classes or
1066class fields.</li>
1067 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1068such modifications MUST NOT impact the stated behavior and Java-language
1069signature of any publicly exposed APIs.</li>
1070 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1071or interfaces, or fields or methods to existing classes or interfaces) to the
1072APIs above.</li>
1073</ul>
1074
1075<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,
1076device implementers MUST NOT expose new APIs or alter existing APIs in the
1077namespaces noted above. Device implementers MAY make internal-only
1078modifications, but those modifications MUST NOT be advertised or otherwise
1079exposed to developers.</p>
1080
1081<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1082namespace owned by or referring to another organization. For instance, device
1083implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1084Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1085namespaces. Additionally, if a device implementation includes custom APIs
1086outside the standard Android namespace, those APIs MUST be packaged in an
1087Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1088lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1089APIs.</p>
1090
1091<p>If a device implementer proposes to improve one of the package namespaces above
1092(such as by adding useful new functionality to an existing API, or adding a new
1093API), 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
1094information on that site.</p>
1095
1096<p>Note that the restrictions above correspond to standard conventions for naming
1097APIs in the Java programming language; this section simply aims to reinforce
1098those conventions and make them binding through inclusion in this Compatibility
1099Definition.</p>
1100
1101<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1102
1103
1104<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1105Dalvik 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
1106the Dalvik Executable Format, and the reference implementation&rsquo;s package
1107management system.</p>
1108
1109<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1110accordance with the upstream Android platform, and as specified by the
1111following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1112
1113<p>Note that memory values specified below are considered minimum values and
1114device implementations MAY allocate more memory per application.</p>
1115
1116<table>
1117 <tr>
1118 <th>Screen Layout</th>
1119 <th>Screen Density</th>
1120 <th>Minimum Application Memory</th>
1121 </tr>
1122 <tr>
1123 <td rowspan="10">small/normal</td>
1124 <td>120 dpi (ldpi)</td>
1125 <td rowspan="2">32MB</td>
1126 </tr>
1127 <tr>
1128 <td>160 dpi (mdpi)</td>
1129 </tr>
1130 <tr>
1131 <td>213 dpi (tvdpi)</td>
1132 <td rowspan="3">48MB</td>
1133 </tr>
1134 <tr>
1135 <td>240 dpi (hdpi)</td>
1136 </tr>
1137 <tr>
1138 <td>280 dpi (280dpi)</td>
1139 </tr>
1140 <tr>
1141 <td>320 dpi (xhdpi)</td>
1142 <td>80MB</td>
1143 </tr>
1144 <tr>
1145 <td>400 dpi (400dpi)</td>
1146 <td>96MB</td>
1147 </tr>
1148 <tr>
1149 <td>480 dpi (xxhdpi)</td>
1150 <td>128MB</td>
1151 </tr>
1152 <tr>
1153 <td>560 dpi (560dpi)</td>
1154 <td>192MB</td>
1155 </tr>
1156 <tr>
1157 <td>640 dpi (xxxhdpi)</td>
1158 <td>256MB</td>
1159 </tr>
1160 <tr>
1161 <td rowspan="10">large</td>
1162 <td>120 dpi (ldpi)</td>
1163 <td>32MB</td>
1164 </tr>
1165 <tr>
1166 <td>160 dpi (mdpi)</td>
1167 <td>48MB</td>
1168 </tr>
1169 <tr>
1170 <td>213 dpi (tvdpi)</td>
1171 <td rowspan="2">80MB</td>
1172 </tr>
1173 <tr>
1174 <td>240 dpi (hdpi)</td>
1175 </tr>
1176 <tr>
1177 <td>280 dpi (280dpi)</td>
1178 <td>96MB</td>
1179 </tr>
1180 <tr>
1181 <td>320 dpi (xhdpi)</td>
1182 <td>128MB</td>
1183 </tr>
1184 <tr>
1185 <td>400 dpi (400dpi)</td>
1186 <td>192MB</td>
1187 </tr>
1188 <tr>
1189 <td>480 dpi (xxhdpi)</td>
1190 <td>256MB</td>
1191 </tr>
1192 <tr>
1193 <td>560 dpi (560dpi)</td>
1194 <td>384MB</td>
1195 </tr>
1196 <tr>
1197 <td>640 dpi (xxxhdpi)</td>
1198 <td>512MB</td>
1199 </tr>
1200 <tr>
1201 <td rowspan="10">xlarge</td>
1202 <td>120 dpi (ldpi)</td>
1203 <td>48MB</td>
1204 </tr>
1205 <tr>
1206 <td>160 dpi (mdpi)</td>
1207 <td>80MB</td>
1208 </tr>
1209 <tr>
1210 <td>213 dpi (tvdpi)</td>
1211 <td rowspan="2">96MB</td>
1212 </tr>
1213 <tr>
1214 <td>240 dpi (hdpi)</td>
1215 </tr>
1216 <tr>
1217 <td>280 dpi (280dpi)</td>
1218 <td>144MB</td>
1219 </tr>
1220 <tr>
1221 <td>320 dpi (xhdpi)</td>
1222 <td>192MB</td>
1223 </tr>
1224 <tr>
1225 <td>400 dpi (400dpi)</td>
1226 <td>288MB</td>
1227 </tr>
1228 <tr>
1229 <td>480 dpi (xxhdpi)</td>
1230 <td>384MB</td>
1231 </tr>
1232 <tr>
1233 <td>560 dpi (560dpi)</td>
1234 <td>576MB</td>
1235 </tr>
1236 <tr>
1237 <td>640 dpi (xxxhdpi)</td>
1238 <td>768MB</td>
1239 </tr>
1240</table>
1241
1242
1243<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1244
1245
1246<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1247
1248
1249<p>Android includes a launcher application (home screen) and support for
1250third-party applications to replace the device launcher (home screen). Device
1251implementations that allow third-party applications to replace the device home
1252screen MUST declare the platform feature android.software.home_screen.</p>
1253
1254<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1255
1256<div class="note">
1257<p>Widgets are optional for all Android device implementations, but SHOULD be
1258supported on Android Handheld devices.</p>
1259</div>
1260
1261
1262<p>Android defines a component type and corresponding API and lifecycle that
1263allows 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
1264implementations. Device implementations that support embedding widgets on the
1265home screen MUST meet the following requirements and declare support for
1266platform feature android.software.app_widgets.</p>
1267
1268<ul>
1269 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1270interface affordances to add, configure, view, and remove AppWidgets directly
1271within the Launcher.</li>
1272 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1273the standard grid size. See the App Widget Design Guidelines in the Android SDK
1274documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1275 <li>Device implementations that include support for lock screen MAY support
1276application widgets on the lock screen.</li>
1277</ul>
1278
1279<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1280
1281
1282<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>
1283
1284<p>Some APIs allow applications to perform notifications or attract attention
1285using hardware&#8212;specifically sound, vibration, and light. Device implementations
1286MUST support notifications that use hardware features, as described in the SDK
1287documentation, and to the extent possible with the device implementation
1288hardware. For instance, if a device implementation includes a vibrator, it MUST
1289correctly implement the vibration APIs. If a device implementation lacks
1290hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1291is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1292
1293<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1294etc.) provided for in the APIs
1295[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1296or in the Status/System Bar icon style guide
1297[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1298which in the case of an Android Television device includes the possibility to not display the
1299notifications. Device implementers MAY provide an alternative user experience for
1300notifications than that provided by the reference Android Open Source
1301implementation; however, such alternative notification systems MUST support
1302existing notification resources, as above. </p>
1303
1304<p>Android includes support for various notifications, such as:</p>
1305
1306<ul>
1307 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1308 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1309 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1310</ul>
1311
1312<p>Android device implementations, when such notifications are made visible, MUST properly execute
1313Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1314APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1315</p>
1316
1317<p>Android includes Notification Listener Service APIs that allow apps (once
1318explicitly enabled by the user) to receive a copy of all notifications as they
1319are posted or updated. Device implementations MUST correctly and promptly send
1320notifications in their entirety to all such installed and user-enabled listener
1321services, including any and all metadata attached to the Notification object.</p>
1322
1323<h3 id="3_8_4_search">3.8.4. Search</h3>
1324
1325
1326<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
1327expose their application&rsquo;s data into the global system search. Generally
1328speaking, this functionality consists of a single, system-wide user interface
1329that allows users to enter queries, displays suggestions as users type, and
1330displays results. The Android APIs allow developers to reuse this interface to
1331provide search within their own apps, and allow developers to supply results to
1332the common global search user interface.</p>
1333
1334<p>Android device implementations SHOULD include global search, a single, shared,
1335system-wide search user interface capable of real-time suggestions in response
1336to user input. Device implementations SHOULD implement the APIs that allow
1337developers to reuse this user interface to provide search within their own
1338applications. Device implementations that implement the global search interface
1339MUST implement the APIs that allow third-party applications to add suggestions
1340to the search box when it is run in global search mode. If no third-party
1341applications are installed that make use of this functionality, the default
1342behavior SHOULD be to display web search engine results and suggestions.</p>
1343
1344<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1345
1346
1347<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1348end 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
1349some high-visibility manner.</p>
1350
1351<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1352
1353
1354<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1355across an entire Activity or application.</p>
1356
1357<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1358application developers to use if they want to match the Holo theme look and
1359feel 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
1360exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1361
1362<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1363application developers to use if they want to match the design theme&rsquo;s look and
1364feel across the wide variety of different Android device types. Device
1365implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1366of 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>
1367
1368<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1369styles for application developers to use if they want to match the look and
1370feel of the device theme as defined by the device implementer. Device
1371implementations MAY modify the Device Default theme attributes exposed to
1372applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1373
1374<p>Android supports a new variant theme with translucent system bars, which allows
1375application developers to fill the area behind the status and navigation bar
1376with their app content. To enable a consistent developer experience in this
1377configuration, it is important the status bar icon style is maintained across
1378different device implementations. Therefore, Android device implementations
1379MUST use white for system status icons (such as signal strength and battery
1380level) and notifications issued by the system, unless the icon is indicating a
1381problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1382
1383<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1384
1385
1386<p>Android defines a component type and corresponding API and lifecycle that
1387allows 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
1388input capabilities that display as a wallpaper, behind other applications.</p>
1389
1390<p>Hardware is considered capable of reliably running live wallpapers if it can
1391run all live wallpapers, with no limitations on functionality, at a reasonable
1392frame rate with no adverse effects on other applications. If limitations in the
1393hardware cause wallpapers and/or applications to crash, malfunction, consume
1394excessive CPU or battery power, or run at unacceptably low frame rates, the
1395hardware is considered incapable of running live wallpaper. As an example, some
1396live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1397Live wallpaper will not run reliably on hardware that does not support multiple
1398OpenGL contexts because the live wallpaper use of an OpenGL context may
1399conflict with other applications that also use an OpenGL context.</p>
1400
1401<p>Device implementations capable of running live wallpapers reliably as described
1402above SHOULD implement live wallpapers, and when implemented MUST report the
1403platform feature flag android.software.live_wallpaper.</p>
1404
1405<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1406
1407<div class="note">
1408<p>As the Recent function navigation key is OPTIONAL, the requirements to
1409implement the overview screen is OPTIONAL for Android Television devices and
1410Android Watch devices.</p>
1411</div>
1412
1413
1414<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
1415accessed activities and tasks using a thumbnail image of the application&rsquo;s
1416graphical state at the moment the user last left the application. Device
1417implementations 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>
1418
1419<ul>
1420 <li>MUST display affiliated recents as a group that moves together.</li>
1421 <li>MUST support at least up to 20 displayed activities.</li>
1422 <li>MUST at least display the title of 4 activities at a time.</li>
1423 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1424 <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>
1425 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1426interacts with screens.</li>
1427</ul>
1428
1429<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1430interface (or a similar thumbnail-based interface) for the overview screen.</p>
1431
1432<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1433
1434
1435<p>Android includes support for Input Management and support for third-party input
1436method 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
1437the device MUST declare the platform feature android.software.input_methods and
1438support IME APIs as defined in the Android SDK documentation.</p>
1439
1440<p>Device implementations that declare the android.software.input_methods feature
1441MUST provide a user-accessible mechanism to add and configure third-party input
1442methods. Device implementations MUST display the settings interface in response
1443to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1444
1445<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1446
1447
1448<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1449Media Notification Template that allows media applications to integrate with
1450playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1451Device implementations that support a lock screen, unless an Android Automotive or Watch
1452implementation, MUST display the Lockscreen Notifications including the Media Notification
1453Template.</p>
1454
1455<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1456
1457
1458<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
1459a power source is idle or docked in a desk dock. Android Watch devices MAY
1460implement Dreams, but other types of device implementations SHOULD include
1461support for Dreams and provide a settings option for users to configure Dreams
1462in response to the android.settings.DREAM_SETTINGS intent.</p>
1463
1464<h3 id="3_8_12_location">3.8.12. Location</h3>
1465
1466
1467<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1468location coordinates, location modes MUST be displayed in the Location menu
1469within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1470
1471<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1472
1473
1474<p>Android includes support for color emoji characters. When Android device
1475implementations include an IME, devices SHOULD provide an input method to the
1476user 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>
1477
1478<p>Android includes support for Roboto 2 font with different
1479weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1480sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1481the languages available on the device and full Unicode 7.0 coverage of Latin,
1482Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1483all glyphs in the currency symbols block of Unicode 7.0.</p>
1484
1485<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1486
1487
1488<p>Android includes features that allow security-aware applications to perform
1489device administration functions at the system level, such as enforcing password
1490policies or performing remote wipe, through the Android Device Administration
1491API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1492Device implementations MUST provide an implementation of the DevicePolicyManager class
1493[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1494Device implementations that include support for PIN (numeric) or PASSWORD
1495(alphanumeric) based lock screens MUST support the full range of device
1496administration policies defined in the Android SDK documentation
1497[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1498and report the platform feature android.software.device_admin.</p>
1499
1500<p>Device implementations MAY have a preinstalled application performing device
1501administration functions but this application MUST NOT be set out-of-the box as
1502the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1503
1504<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1505
1506
1507<p>Android provides an accessibility layer that helps users with disabilities to
1508navigate their devices more easily. In addition, Android provides platform APIs
1509that enable accessibility service implementations to receive callbacks for user
1510and system events and generate alternate feedback mechanisms, such as
1511text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1512
1513<p>Device implementations include the following requirements:</p>
1514
1515<ul>
1516<li>Android Automotive implementations SHOULD provide an implementation of the
1517Android accessibility framework consistent with the default Android
1518implementation.</li>
1519<li>Device implementations (Android Automotive excluded) MUST provide an
1520implementation of the Android accessibility framework consistent with the
1521default Android implementation.</li>
1522<li>Device implementations (Android Automotive excluded) MUST support
1523third-party accessibility service implementations through the
1524android.accessibilityservice APIs
1525[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1526<li>Device implementations (Android Automotive excluded) MUST generate
1527AccessibilityEvents and deliver these events to all registered
1528AccessibilityService implementations in a manner consistent with the default
1529Android implementation</li>
1530<li> Device implementations (Android Automotive and Android Watch devices with
1531no audio output excluded), MUST provide a user-accessible mechanism to enable
1532and disable accessibility services, and MUST display this interface in response
1533to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1534</ul>
1535
1536<p>Additionally, device implementations SHOULD provide an implementation of an
1537accessibility service on the device, and SHOULD provide a mechanism for users
1538to enable the accessibility service during device setup. An open source
1539implementation of an accessibility service is available from the Eyes Free
1540project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1541
1542<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1543
1544
1545<p>Android includes APIs that allow applications to make use of text-to-speech
1546(TTS) services and allows service providers to provide implementations of TTS
1547services [<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
1548MUST meet these requirements related to the Android TTS framework. </p>
1549
1550<p>Android Automotive implementations:</p>
1551<ul>
1552<li>MUST support the Android TTS framework APIs.</li>
1553<li>MAY support installation of third-party TTS engines. If supported, partners
1554MUST provide a user-accessible interface that allows the user to select a TTS
1555engine for use at system level.</li>
1556</ul>
1557
1558<p>All other device implementations:</p>
1559
1560<ul>
1561 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1562supporting the languages available on the device. Note that the upstream
1563Android open source software includes a full-featured TTS engine
1564implementation.
1565 <li> MUST support installation of third-party TTS engines
1566 <li> MUST provide a user-accessible interface that allows users to select a TTS
1567engine for use at the system level
1568</ul>
1569
1570<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1571
1572
1573<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1574content to Android Television devices. TIF provides a standard API to create
1575input modules that control Android Television devices. Android Television
1576device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1577
1578<p>Device implementations that support TIF MUST declare the platform feature
1579android.software.live_tv.</p>
1580
1581<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1582
1583
1584<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1585by 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>
1586
1587<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
1588files from installing and running correctly on other compatible devices.</p>
1589
1590<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1591
1592
1593<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1594
1595
1596<p>Device implementations MUST support the core media formats specified in the
1597Android 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
1598implementations MUST support the media formats, encoders, decoders, file types,
1599and container formats defined in the tables below and reported via MediaCodecList
1600[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1601Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1602[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1603113</a>].
1604
1605All of these codecs are
1606provided as software implementations in the preferred Android implementation
1607from the Android Open Source Project.</p>
1608
1609<p>Please note that neither Google nor the Open Handset Alliance make any
1610representation that these codecs are free from third-party patents. Those
1611intending to use this source code in hardware or software products are advised
1612that implementations of this code, including in open source software or
1613shareware, may require patent licenses from the relevant patent holders.</p>
1614
1615<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1616
1617<table>
1618 <tr>
1619 <th>Format/Codec</th>
1620 <th>Encoder</th>
1621 <th>Decoder</th>
1622 <th>Details</th>
1623 <th>Supported File Types/Container Formats</th>
1624 </tr>
1625 <tr>
1626 <td>MPEG-4 AAC Profile</p>
1627
1628<p>(AAC LC)</td>
1629 <td>REQUIRED<sup>1</sup></td>
1630 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1631 <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]163248 kHz.</td>
1633 <td>
1634 <ul>
1635 <li class="table_list">3GPP (.3gp)</li>
1636 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1637 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1638supported)</li>
1639 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1640 </tr>
1641 <tr>
1642 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1643 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1644 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1645 <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]1646to 48 kHz.</td>
1647 <td></td>
1648 </tr>
1649 <tr>
1650 <td>MPEG-4 HE AACv2</p>
1651
1652<p>Profile (enhanced AAC+)</td>
1653 <td> </td>
1654 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1655 <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]1656to 48 kHz.</td>
1657 <td></td>
1658 </tr>
1659 <tr>
1660 <td>AAC ELD (enhanced low delay AAC)</td>
1661 <td>REQUIRED<sup>1</sup> </p>
1662
1663<p>(Android 4.1+)</td>
1664 <td>REQUIRED</p>
1665
1666<p>(Android 4.1+)</td>
1667 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1668 <td></td>
1669 </tr>
1670 <tr>
1671 <td>AMR-NB</td>
1672 <td>REQUIRED<sup>3</sup></td>
1673 <td>REQUIRED<sup>3</sup></td>
1674 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1675 <td>3GPP (.3gp)</td>
1676 </tr>
1677 <tr>
1678 <td>AMR-WB</td>
1679 <td>REQUIRED<sup>3</sup></td>
1680 <td>REQUIRED<sup>3</sup></td>
1681 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1682 <td></td>
1683 </tr>
1684 <tr>
1685 <td>FLAC</td>
1686 <td></td>
1687 <td>REQUIRED <br>(Android 3.1+)</td>
1688 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1689recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1690does not include a low-pass filter). 16-bit recommended; no dither applied for
169124-bit.</td>
1692 <td>FLAC (.flac) only</td>
1693 </tr>
1694 <tr>
1695 <td>MP3</td>
1696 <td></td>
1697 <td>REQUIRED</td>
1698 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1699 <td>MP3 (.mp3)</td>
1700 </tr>
1701 <tr>
1702 <td>MIDI</td>
1703 <td></td>
1704 <td>REQUIRED</td>
1705 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1706ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1707 <td><ul>
1708 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1709 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1710 <li class="table_list">OTA (.ota)</li>
1711 <li class="table_list">iMelody (.imy)</li></ul></td>
1712 </tr>
1713 <tr>
1714 <td>Vorbis</td>
1715 <td></td>
1716 <td>REQUIRED</td>
1717 <td></td>
1718 <td><ul>
1719 <li class="table_list">Ogg (.ogg)</li>
1720 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1721 </tr>
1722 <tr>
1723 <td>PCM/WAVE</td>
1724 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1725 <td>REQUIRED</td>
1726 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1727sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1728frequencies.</td>
1729 <td>WAVE (.wav)</td>
1730 </tr>
1731 <tr>
1732 <td>Opus</td>
1733 <td></td>
1734 <td>REQUIRED<br> (Android 5.0+)</td>
1735 <td></td>
1736 <td>Matroska (.mkv)</td>
1737 </tr>
1738</table>
1739
1740
1741<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1742but optional for Android Watch device implementations.</p>
1743
1744<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17452 channels is optional.</p>
1746
1747<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1748
1749<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1750including Android Watch device implementations.</p>
1751
1752<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1753
1754<table>
1755 <tr>
1756 <th>Format/Codec</th>
1757 <th>Encoder</th>
1758 <th>Decoder</th>
1759 <th>Details</th>
1760 <th>Supported File Types/Container Formats</th>
1761 </tr>
1762 <tr>
1763 <td>JPEG</td>
1764 <td>REQUIRED</td>
1765 <td>REQUIRED</td>
1766 <td>Base+progressive</td>
1767 <td>JPEG (.jpg)</td>
1768 </tr>
1769 <tr>
1770 <td>GIF</td>
1771 <td></td>
1772 <td>REQUIRED</td>
1773 <td></td>
1774 <td>GIF (.gif)</td>
1775 </tr>
1776 <tr>
1777 <td>PNG</td>
1778 <td>REQUIRED</td>
1779 <td>REQUIRED</td>
1780 <td></td>
1781 <td>PNG (.png)</td>
1782 </tr>
1783 <tr>
1784 <td>BMP</td>
1785 <td></td>
1786 <td>REQUIRED</td>
1787 <td></td>
1788 <td>BMP (.bmp)</td>
1789 </tr>
1790 <tr>
1791 <td>WebP</td>
1792 <td>REQUIRED</td>
1793 <td>REQUIRED</td>
1794 <td></td>
1795 <td>WebP (.webp)</td>
1796 </tr>
1797</table>
1798
1799
1800<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1801
1802<p>Video codecs are optional for Android Watch device implementations.</p>
1803
1804<table>
1805 <tr>
1806 <th>Format/Codec</th>
1807 <th>Encoder</th>
1808 <th>Decoder</th>
1809 <th>Details</th>
1810 <th>Supported File Types/<br>Container Formats</th>
1811 </tr>
1812 <tr>
1813 <td>H.263</td>
1814 <td>REQUIRED<sup>1</sup></td>
1815 <td>REQUIRED<sup>2</sup></td>
1816 <td></td>
1817 <td><ul>
1818 <li class="table_list">3GPP (.3gp)</li>
1819 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1820 </tr>
1821 <tr>
1822 <td>H.264 AVC</td>
1823 <td>REQUIRED<sup>2</sup></td>
1824 <td>REQUIRED<sup>2</sup></td>
1825 <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>
1826 <td><ul>
1827 <li class="table_list">3GPP (.3gp)</li>
1828 <li class="table_list">MPEG-4 (.mp4)</li>
1829 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1830 </tr>
1831 <tr>
1832 <td>H.265 HEVC</td>
1833 <td></td>
1834 <td>REQUIRED<sup>5</sup></td>
1835 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1836 <td>MPEG-4 (.mp4)</td>
1837 </tr>
1838 <tr>
1839 <td>MPEG-4 SP</td>
1840 <td></td>
1841 <td>REQUIRED<sup>2</sup></td>
1842 <td></td>
1843 <td>3GPP (.3gp)</td>
1844 </tr>
1845 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1846 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1847 <td>REQUIRED<sup>2</sup></p>
1848
1849<p>(Android 4.3+)</td>
1850 <td>REQUIRED<sup>2</sup></p>
1851
1852<p>(Android 2.3.3+)</td>
1853 <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>
1854 <td><ul>
1855 <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]1856 <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]1857 </tr>
1858 <tr>
1859 <td>VP9</td>
1860 <td></td>
1861 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1862 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1863 <td><ul>
1864 <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]1865 <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]1866 </tr>
1867</table>
1868
1869
1870<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1871android.hardware.camera or android.hardware.camera.front.</p>
1872
1873<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1874
1875<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1876device implementations SHOULD use a hardware VP8 codec that meets the
1877requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1878
1879<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1880
1881<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1882
1883<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1884
1885<div class="note">
1886<p>Video codecs are optional for Android Watch device implementations.</p>
1887</div>
1888
1889
1890<p>Android device implementations with H.264 codec support, MUST support Baseline
1891Profile Level 3 and the following SD (Standard Definition) video encoding
1892profiles and SHOULD support Main Profile Level 4 and the following HD (High
1893Definition) video encoding profiles. Android Television devices are STRONGLY
1894RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1895<table>
1896 <tr>
1897 <th></th>
1898 <th>SD (Low quality)</th>
1899 <th>SD (High quality)</th>
1900 <th>HD 720p1</th>
1901 <th>HD 1080p1</th>
1902 </tr>
1903 <tr>
1904 <th>Video resolution</th>
1905 <td>320 x 240 px</td>
1906 <td>720 x 480 px</td>
1907 <td>1280 x 720 px</td>
1908 <td>1920 x 1080 px</td>
1909 </tr>
1910 <tr>
1911 <th>Video frame rate</th>
1912 <td>20 fps</td>
1913 <td>30 fps</td>
1914 <td>30 fps</td>
1915 <td>30 fps</td>
1916 </tr>
1917 <tr>
1918 <th>Video bitrate</th>
1919 <td>384 Kbps</td>
1920 <td>2 Mbps</td>
1921 <td>4 Mbps</td>
1922 <td>10 Mbps</td>
1923 </tr>
1924</table>
1925
1926
1927<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1928devices.</p>
1929
1930<p>Android device implementations with VP8 codec support MUST support the SD video
1931encoding profiles and SHOULD support the following HD (High Definition) video
1932encoding profiles.</p>
1933<table>
1934 <tr>
1935 <th></th>
1936 <th>SD (Low quality)</th>
1937 <th>SD (High quality)</th>
1938 <th>HD 720p1</th>
1939 <th>HD 1080p1</th>
1940 </tr>
1941 <tr>
1942 <th>Video resolution</th>
1943 <td>320 x 180 px</td>
1944 <td>640 x 360 px</td>
1945 <td>1280 x 720 px</td>
1946 <td>1920 x 1080 px</td>
1947 </tr>
1948 <tr>
1949 <th>Video frame rate</th>
1950 <td>30 fps</td>
1951 <td>30 fps</td>
1952 <td>30 fps</td>
1953 <td>30 fps</td>
1954 </tr>
1955 <tr>
1956 <th>Video bitrate</th>
1957 <td>800 Kbps </td>
1958 <td>2 Mbps</td>
1959 <td>4 Mbps</td>
1960 <td>10 Mbps</td>
1961 </tr>
1962</table>
1963
1964<p class="table_footnote">1 When supported by hardware.</p>
1965
1966<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1967
1968<div class="note">
1969<p>Video codecs are optional for Android Watch device implementations.</p>
1970</div>
1971
1972
1973<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1974the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1975standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1976
1977<p>Android device implementations with H.264 decoders, MUST support Baseline
1978Profile Level 3 and the following SD video decoding profiles and SHOULD support
1979the HD decoding profiles. Android Television devices MUST support High Profile
1980Level 4.2 and the HD 1080p decoding profile.</p>
1981<table>
1982 <tr>
1983 <th></th>
1984 <th>SD (Low quality)</th>
1985 <th>SD (High quality)</th>
1986 <th>HD 720p1</th>
1987 <th>HD 1080p1</th>
1988 </tr>
1989 <tr>
1990 <th>Video resolution</th>
1991 <td>320 x 240 px</td>
1992 <td>720 x 480 px</td>
1993 <td>1280 x 720 px</td>
1994 <td>1920 x 1080 px</td>
1995 </tr>
1996 <tr>
1997 <th>Video frame rate</th>
1998 <td>30 fps</td>
1999 <td>30 fps</td>
2000 <td>30 fps / 60 fps2</td>
2001 <td>30 fps / 60 fps2</td>
2002 </tr>
2003 <tr>
2004 <th>Video bitrate</th>
2005 <td>800 Kbps </td>
2006 <td>2 Mbps</td>
2007 <td>8 Mbps</td>
2008 <td>20 Mbps</td>
2009 </tr>
2010</table>
2011
2012
2013<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2014types only when supported by hardware.</p>
2015
2016<p class="table_footnote">2 Required for Android Television device implementations.</p>
2017
2018<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
2019decoding profiles. Android Television devices MUST support the HD 1080p
2020decoding profile. </p>
2021<table>
2022 <tr>
2023 <th></th>
2024 <th>SD (Low quality)</th>
2025 <th>SD (High quality)</th>
2026 <th>HD 720p1</th>
2027 <th>HD 1080p1</th>
2028 </tr>
2029 <tr>
2030 <th>Video resolution</th>
2031 <td>320 x 180 px</td>
2032 <td>640 x 360 px</td>
2033 <td>1280 x 720 px</td>
2034 <td>1920 x 1080 px</td>
2035 </tr>
2036 <tr>
2037 <th>Video frame rate</th>
2038 <td>30 fps</td>
2039 <td>30 fps</td>
2040 <td>30 fps / 60 fps2</td>
2041 <td>30 / 60 fps2</td>
2042 </tr>
2043 <tr>
2044 <th>Video bitrate</th>
2045 <td>800 Kbps </td>
2046 <td>2 Mbps</td>
2047 <td>8 Mbps</td>
2048 <td>20 Mbps</td>
2049 </tr>
2050</table>
2051
2052
2053<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2054devices only when supported by hardware.</p>
2055
2056<p class="table_footnote">2 Required for Android Television device implementations.</p>
2057
2058<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
2059HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2060support the HD 1080p decoding profile and SHOULD support the UHD decoding
2061profile. When the UHD video decoding profile is supported, it MUST support 8
2062bit color depth.</p>
2063<table>
2064 <tr>
2065 <th></th>
2066 <th>SD (Low quality)</th>
2067 <th>SD (High quality)</th>
2068 <th>HD 720p 1</th>
2069 <th>HD 1080p 2</th>
2070 <th>UHD 2</th>
2071 </tr>
2072 <tr>
2073 <th>Video resolution</th>
2074 <td>320 x 180 px</td>
2075 <td>640 x 360 px</td>
2076 <td>1280 x 720 px</td>
2077 <td>1920 x 1080 px</td>
2078 <td>3840 x 2160 px</td>
2079 </tr>
2080 <tr>
2081 <th>Video frame rate</th>
2082 <td>30 fps</td>
2083 <td>30 fps</td>
2084 <td>30 fps</td>
2085 <td>30 fps</td>
2086 <td>30 fps</td>
2087 </tr>
2088 <tr>
2089 <th>Video bitrate</th>
2090 <td>600 Kbps </td>
2091 <td>1.6 Mbps</td>
2092 <td>4 Mbps</td>
2093 <td>10 Mbps</td>
2094 <td>20 Mbps</td>
2095 </tr>
2096</table>
2097
2098
2099<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2100devices only when supported by hardware.</p>
2101
2102<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2103supported by hardware.</p>
2104
2105<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
2106decoding profiles and SHOULD support the HD decoding profiles. Android
2107Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21081080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2109the UHD decoding profile.</p>
2110<table>
2111 <tr>
2112 <th></th>
2113 <th>SD (Low quality)</th>
2114 <th>SD (High quality)</th>
2115 <th>HD 720p </strong>1 </td>
2116 <th>HD 1080p </strong>1 </td>
2117 <th>UHD </strong>2</td>
2118 </tr>
2119 <tr>
2120 <th>Video resolution</th>
2121 <td>352 x 288 px</td>
2122 <td>640 x 360 px</td>
2123 <td>1280 x 720 px</td>
2124 <td>1920 x 1080 px</td>
2125 <td>3840 x 2160 px</td>
2126 </tr>
2127 <tr>
2128 <th>Video frame rate</th>
2129 <td>30 fps</td>
2130 <td>30 fps</td>
2131 <td>30 fps</td>
2132 <td>30 fps</td>
2133 <td>30 fps</td>
2134 </tr>
2135 <tr>
2136 <th>Video bitrate</th>
2137 <td>600 Kbps </td>
2138 <td>1.6 Mbps</td>
2139 <td>4 Mbps</td>
2140 <td>10 Mbps</td>
2141 <td>20 Mbps</td>
2142 </tr>
2143</table>
2144
2145
2146<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2147devices only when supported by hardware.</p>
2148
2149<p class="table_footnote">2 Required for Android Television device implementations when supported by
2150hardware.</p>
2151
2152<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2153
2154
2155<p>While some of the requirements outlined in this section are stated as SHOULD
2156since Android 4.3, the Compatibility Definition for a future version is planned
2157to 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
2158compatibility when upgraded to the future version.</p>
2159
2160<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2161
2162
2163<p>Device implementations that declare android.hardware.microphone MUST allow
2164capture of raw audio content with the following characteristics:</p>
2165
2166<ul>
2167 <li><strong>Format</strong>: Linear PCM, 16-bit
2168 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2169 <li><strong>Channels</strong>: Mono
2170</ul>
2171
2172<p>Device implementations that declare android.hardware.microphone SHOULD allow
2173capture of raw audio content with the following characteristics:</p>
2174
2175<ul>
2176 <li><strong>Format</strong>: Linear PCM, 16-bit
2177 <li><strong>Sampling rates</strong>: 22050, 48000
2178 <li><strong>Channels</strong>: Stereo
2179</ul>
2180
2181<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2182
2183
2184<p>In addition to the above recording specifications, when an application has
2185started recording an audio stream using the
2186android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2187
2188<ul>
2189 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2190characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2191 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2192source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2193 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2194dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2195 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2196level at the microphone.
2197 <li>Noise reduction processing, if present, MUST be disabled.
2198 <li>Automatic gain control, if present, MUST be disabled
2199</ul>
2200
2201<p>If the platform supports noise suppression technologies tuned for speech
2202recognition, the effect MUST be controllable from the
2203android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2204noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2205of the noise suppression technology.</p>
2206
2207<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2208
2209
2210<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2211audio source. Devices that declare android.hardware.audio.output MUST properly
2212implement the REMOTE_SUBMIX audio source so that when an application uses the
2213android.media.AudioRecord API to record from this audio source, it can capture
2214a mix of all audio streams except for the following:</p>
2215
2216<ul>
2217 <li>STREAM_RING
2218 <li>STREAM_ALARM
2219 <li>STREAM_NOTIFICATION
2220</ul>
2221
2222<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2223
2224
2225<p>Device implementations that declare android.hardware.audio.output MUST conform
2226to the requirements in this section.</p>
2227
2228<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2229
2230
2231<p>The device MUST allow playback of raw audio content with the following
2232characteristics:</p>
2233
2234<ul>
2235 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2236 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2237 <li><strong>Channels</strong>: Mono, Stereo</li>
2238</ul>
2239
2240<p>The device SHOULD allow playback of raw audio content with the following
2241characteristics:</p>
2242
2243<ul>
2244 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2245</ul>
2246
2247<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2248
2249
2250<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
2251android.hardware.audio.output:</p>
2252
2253<ul>
2254 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2255implementations controllable through the AudioEffect subclasses Equalizer,
2256LoudnessEnhancer.</li>
2257 <li>MUST support the visualizer API implementation, controllable through the
2258Visualizer class.</li>
2259 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2260EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2261controllable through the AudioEffect sub-classes BassBoost,
2262EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2263</ul>
2264
2265<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2266
2267
2268<p>Android Television device implementations MUST include support for system
2269Master Volume and digital audio output volume attenuation on supported outputs,
2270except for compressed audio passthrough output (where no audio decoding is done
2271on the device).</p>
2272
2273<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2274
2275
2276<p>Audio latency is the time delay as an audio signal passes through a system.
2277Many classes of applications rely on short latencies, to achieve real-time
2278sound effects.</p>
2279
2280<p>For the purposes of this section, use the following definitions:</p>
2281
2282<ul>
2283 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2284when the corresponding sound can be heard by an external listener or observed
2285by a transducer.</li>
2286 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2287idle and powered down prior to the request.</li>
2288 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2289 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2290when an application reads the corresponding frame of PCM-coded data.</li>
2291 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2292audio input system has been idle and powered down prior to the request.</li>
2293 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2294 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2295 <li><strong>cold input jitter</strong>. The variance among separate measurements of cold input latency values.</li>
2296 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus 5
2297milliseconds.</li>
2298 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2299NDK_root/docs/opensles/index.html.</li>
2300</ul>
2301
2302<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2303or exceed these audio output requirements:</p>
2304
2305<ul>
2306 <li>cold output latency of 100 milliseconds or less</li>
2307 <li>continuous output latency of 45 milliseconds or less</li>
2308 <li>minimize the cold output jitter</li>
2309</ul>
2310
2311<p>If a device implementation meets the requirements of this section after any
2312initial calibration when using the OpenSL ES PCM buffer queue API, for
2313continuous output latency and cold output latency over at least one supported
2314audio output device, it MAY report support for low-latency audio, by reporting
2315the feature android.hardware.audio.low_latency via the
2316android.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
2317MUST NOT report support for low-latency audio.</p>
2318
2319<p>Device implementations that include android.hardware.microphone SHOULD meet
2320these input audio requirements:</p>
2321
2322<ul>
2323 <li>cold input latency of 100 milliseconds or less</li>
2324 <li>continuous input latency of 30 milliseconds or less</li>
2325 <li>continuous round-trip latency of 50 milliseconds or less</li>
2326 <li>minimize the cold input jitter</li>
2327</ul>
2328
2329<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2330
2331
2332<p>Devices MUST support the media network protocols for audio and video playback
2333as 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>
2334
2335<ul>
2336 <li>RTSP (RTP, SDP)</li>
2337 <li>HTTP(S) progressive streaming</li>
2338 <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>
2339</ul>
2340
2341<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2342
2343
2344<p>Device implementations that support secure video output and are capable of
2345supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2346implementations that declare support for Display.FLAG_SECURE, if they support a
2347wireless display protocol, MUST secure the link with a cryptographically strong
2348mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2349if they support a wired external display, the device implementations MUST
2350support HDCP 1.2 or higher. Android Television device implementations MUST
2351support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2352lower resolutions. The upstream Android open source implementation includes
2353support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2354requirement.</p>
2355
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2356<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2357
2358<p>
2359If a device implementation supports the inter-app MIDI software transport
2360(virtual MIDI devices), and it supports MIDI over
2361<em>all</em> of the following MIDI-capable hardware transports
2362for which it provides generic non-MIDI connectivity, it MAY report
2363support for feature android.software.midi via the
2364android.content.pm.PackageManager class
2365[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2366</p>
2367
2368<p>The MIDI-capable hardware transports are:</p>
2369<ul>
2370 <li>USB host mode (section 7.7 USB)</li>
2371 <li>USB peripheral mode (section 7.7 USB)</li>
2372</ul>
2373
2374<p>
2375Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2376MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2377it MUST NOT report support for feature android.software.midi.
2378</p>
2379
2380<p>
2381MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2382is in trial use status. A device implementation that reports
2383feature android.software.midi, and which provides generic non-MIDI connectivity
2384over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2385</p>
2386
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2387<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2388
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2389<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2390
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2391<p>Device implementations MUST support the Android Developer Tools provided in the
2392Android SDK. Android compatible devices MUST be compatible with:</p>
2393
2394<ul>
2395 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2396</ul>
2397
2398<p>Device implementations MUST support all adb functions as documented in the
2399Android 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
2400user-accessible mechanism to turn on the Android Debug Bridge. If a device
2401implementation omits USB peripheral mode, it MUST implement the Android Debug
2402Bridge via local-area network (such as Ethernet or 802.11). </p>
2403
2404<p>Android includes support for secure adb. Secure adb enables adb on known
2405authenticated hosts. Device implementations MUST support secure adb.</p>
2406
2407<ul>
2408 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2409</ul>
2410
2411<p>Device implementations MUST support all ddms features as documented in the
2412Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2413but MUST be supported whenever the user has activated the Android Debug Bridge,
2414as above.</p>
2415
2416<ul>
2417 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2418</ul>
2419
2420<p>Device implementations MUST include the Monkey framework, and make it available
2421for applications to use.</p>
2422
2423<ul>
2424 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2425</ul>
2426
2427<p>Device implementations MUST support systrace tool as documented in the Android
2428SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2429mechanism to turn on Systrace.</p>
2430
2431<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2432using the standard Android SDK tools, without additional support; however
2433Microsoft Windows systems typically require a driver for new Android devices.
2434(For instance, new vendor IDs and sometimes new device IDs require custom USB
2435drivers for Windows systems.) If a device implementation is unrecognized by the
2436adb tool as provided in the standard Android SDK, device implementers MUST
2437provide Windows drivers allowing developers to connect to the device using the
2438adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2439Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2440
2441<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2442
2443
2444<p>Android includes support for developers to configure application
2445development-related settings. Device implementations MUST honor the
2446android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2447development-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
2448default and enables users to launch Developer Options after pressing seven (7)
2449times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2450Developer Options. Specifically, device implementations MUST hide Developer
2451Options by default and MUST provide a mechanism to enable Developer Options
2452that is consistent with the upstream Android implementation.</p>
2453
2454<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2455
2456
2457<p>If a device includes a particular hardware component that has a corresponding
2458API for third-party developers, the device implementation MUST implement that
2459API as described in the Android SDK documentation. If an API in the SDK
2460interacts with a hardware component that is stated to be optional and the
2461device implementation does not possess that component:</p>
2462
2463<ul>
2464 <li>Complete class definitions (as documented by the SDK) for the component APIs
2465MUST still be presented.
2466 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2467 <li>API methods MUST return null values where permitted by the SDK documentation.
2468 <li>API methods MUST return no-op implementations of classes where null values are
2469not permitted by the SDK documentation.
2470 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2471</ul>
2472
2473<p>A typical example of a scenario where these requirements apply is the telephony
2474API: even on non-phone devices, these APIs must be implemented as reasonable
2475no-ops.</p>
2476
2477<p>Device implementations MUST consistently report accurate hardware configuration
2478information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2479methods on the android.content.pm.PackageManager class for the same build
2480fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2481
2482<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2483
2484
2485<p>Android includes facilities that automatically adjust application assets and UI
2486layouts appropriately for the device, to ensure that third-party applications
2487run 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
2488this section.</p>
2489
2490<p>The units referenced by the requirements in this section are defined as
2491follows:</p>
2492
2493<ul>
2494 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2495of the display.</li>
2496 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
24971&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2498within the range.</li>
2499 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2500 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2501 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2502 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2503dps * (density/160).</li>
2504</ul>
2505
2506<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2507
2508
2509<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2510
2511<div class="note">
2512<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>
2513</div>
2514
2515<p>The Android UI framework supports a variety of different screen sizes, and
2516allows applications to query the device screen size (aka &ldquo;screen layout") via
2517android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2518Device implementations MUST report the correct screen size as defined in the
2519Android 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
2520implementations MUST report the correct screen size according to the following
2521logical density-independent pixel (dp) screen dimensions.</p>
2522
2523<ul>
2524 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2525is an Android Watch device.</li>
2526 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2527dp x 320 dp.</li>
2528 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2529dp x 480 dp.</li>
2530 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2531dp x 720 dp.</li>
2532</ul>
2533
2534<p>In addition, </p>
2535
2536<ul>
2537 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2538range from 1.1 to 2.5 inches.</li>
2539 <li>Other types of Android device implementations, with a physically integrated
2540screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2541</ul>
2542
2543<p>Devices MUST NOT change their reported screen size at any time.</p>
2544
2545<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2546&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2547implementations MUST correctly honor applications' stated support for small,
2548normal, large, and xlarge screens, as described in the Android SDK
2549documentation.</p>
2550
2551<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2552
2553<div class="note">
2554<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2555</div>
2556
2557
2558<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
255916:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2560such a device implementation will use a UI_MODE_TYPE_WATCH as the
2561android.content.res.Configuration.uiMode.</p>
2562
2563<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2564
2565
2566<p>The Android UI framework defines a set of standard logical densities to help
2567application developers target application resources. Device implementations
2568MUST report only one of the following logical Android framework densities
2569through the android.util.DisplayMetrics APIs, and MUST execute applications at
2570this standard density and MUST NOT change the value at at any time for the
2571default display.</p>
2572
2573<ul>
2574 <li>120 dpi (ldpi)</li>
2575 <li>160 dpi (mdpi)</li>
2576 <li>213 dpi (tvdpi)</li>
2577 <li>240 dpi (hdpi)</li>
2578 <li>280 dpi (280dpi)</li>
2579 <li>320 dpi (xhdpi)</li>
2580 <li>400 dpi (400dpi)</li>
2581 <li>480 dpi (xxhdpi)</li>
2582 <li>560 dpi (560dpi)</li>
2583 <li>640 dpi (xxxhdpi)</li>
2584</ul>
2585
2586<p>Device implementations SHOULD define the standard Android framework density
2587that is numerically closest to the physical density of the screen, unless that
2588logical density pushes the reported screen size below the minimum supported. If
2589the standard Android framework density that is numerically closest to the
2590physical density results in a screen size that is smaller than the smallest
2591supported compatible screen size (320 dp width), device implementations SHOULD
2592report the next lowest standard Android framework density.</p>
2593
2594<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2595
2596
2597<p>Device implementations MUST report correct values for all display metrics
2598defined 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
2599external screen is used as the default display.</p>
2600
2601<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2602
2603
2604<p>Devices MUST report which screen orientations they support
2605(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2606MUST report at least one supported orientation. For example, a device with a
2607fixed orientation landscape screen, such as a television or laptop, SHOULD only
2608report android.hardware.screen.landscape.</p>
2609
2610<p>Devices that report both screen orientations MUST support dynamic orientation
2611by applications to either portrait or landscape screen orientation. That is,
2612the device must respect the application&rsquo;s request for a specific screen
2613orientation. Device implementations MAY select either portrait or landscape
2614orientation as the default.</p>
2615
2616<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2617whenever queried via the android.content.res.Configuration.orientation,
2618android.view.Display.getOrientation(), or other APIs.</p>
2619
2620<p>Devices MUST NOT change the reported screen size or density when changing
2621orientation.</p>
2622
2623<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2624
2625
2626<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2627detailed in the Android SDK documentations. Device implementations SHOULD
2628support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2629implementations MUST also support Android RenderScript, as detailed in the
2630Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2631
2632<p>Device implementations MUST also correctly identify themselves as supporting
2633OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2634
2635<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2636 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2637for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2638 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2639libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2640ES 2.0.</li>
2641 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2642support the corresponding managed APIs and include support for native C/C++
2643APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2644libGLESv2.so MUST export the corresponding function symbols in addition to the
2645OpenGL ES 2.0 function symbols.</li>
2646</ul>
2647
2648<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2649interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2650and the ASTC texture compression format. Android device implementations MAY
2651support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2652support through the android.hardware.opengles.aep feature flag.</p>
2653
2654<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2655However, device implementations MUST report via the OpenGL ES managed and
2656native APIs all extension strings that they do support, and conversely MUST NOT
2657report extension strings that they do not support.</p>
2658
2659<p>Note that Android includes support for applications to optionally specify that
2660they require specific OpenGL texture compression formats. These formats are
2661typically vendor-specific. Device implementations are not required by Android
2662to implement any specific texture compression format. However, they SHOULD
2663accurately report any texture compression formats that they do support, via the
2664getString() method in the OpenGL API.</p>
2665
2666<p>Android includes a mechanism for applications to declare that they want to
2667enable hardware acceleration for 2D graphics at the Application, Activity,
2668Window, or View level through the use of a manifest tag
2669android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2670
2671<p>Device implementations MUST enable hardware acceleration by default, and MUST
2672disable hardware acceleration if the developer so requests by setting
2673android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2674through the Android View APIs.</p>
2675
2676<p>In addition, device implementations MUST exhibit behavior consistent with the
2677Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2678
2679<p>Android includes a TextureView object that lets developers directly integrate
2680hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2681Device implementations MUST support the TextureView API, and MUST exhibit
2682consistent behavior with the upstream Android implementation.</p>
2683
2684<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2685that indicates whether the EGLConfig supports rendering to an ANativeWindow
2686that records images to a video. Device implementations MUST support
2687EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2688
2689<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2690
2691
2692<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2693'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2694applications not developed for old versions of Android that pre-date
2695screen-size independence.</p>
2696
2697<ul>
2698<li>Android Automotive does not support legacy compatibility mode.</li>
2699<li>All other device implementations MUST include support for legacy application
2700compatibility mode as implemented by the upstream Android open source code. That
2701is, device implementations MUST NOT alter the triggers or thresholds at which
2702compatibility mode is activated, and MUST NOT alter the behavior of the
2703compatibility mode itself.</li>
2704</ul>
2705
2706<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2707
2708
2709<p>The Android platform includes APIs that allow applications to render rich
2710graphics to the display. Devices MUST support all of these APIs as defined by
2711the Android SDK unless specifically allowed in this document. </p>
2712
2713<ul>
2714 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2715SHOULD support displays capable of 24-bit color graphics.</li>
2716 <li>Devices MUST support displays capable of rendering animations.</li>
2717 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2718and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
271915% tolerance.</li>
2720</ul>
2721
2722<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2723
2724
2725<p>Android includes support for secondary display to enable media sharing
2726capabilities and developer APIs for accessing external displays. If a device
2727supports an external display either via a wired, wireless, or an embedded
2728additional display connection then the device implementation MUST implement the
2729display 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>
2730
2731<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2732
2733<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2734for non-touch navigation.</p>
2735
2736<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2737
2738<div class="note">
2739<p>Android Watch and Android Automotive implementations MAY implement a soft
2740keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2741</div>
2742
2743
2744<p>Device implementations:</p>
2745
2746<ul>
2747 <li>MUST include support for the Input Management Framework (which allows
2748third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2749detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2750 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2751hard keyboard is present) except for Android Watch devices where the screen
2752size makes it less reasonable to have a soft keyboard.</li>
2753 <li>MAY include additional soft keyboard implementations.</li>
2754 <li>MAY include a hardware keyboard.</li>
2755 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2756specified 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>
2757</ul>
2758
2759<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2760
2761<div class="note">
2762<p>Android Television devices MUST support D-pad.</p>
2763</div>
2764
2765<p>Device implementations:</p>
2766
2767<ul>
2768 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2769device implementation is not an Android Television device.</li>
2770 <li>MUST report the correct value for android.content.res.Configuration.navigation
2771[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2772 <li>MUST provide a reasonable alternative user interface mechanism for the
2773selection and editing of text, compatible with Input Management Engines. The
2774upstream Android open source implementation includes a selection mechanism
2775suitable for use with devices that lack non-touch navigation inputs.</li>
2776</ul>
2777
2778<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2779
2780<div class="note">
2781<p>The availability and visibility requirement of the Home, Recents, and Back
2782functions differ between device types as described in this section.</p>
2783</div>
2784
2785<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2786KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2787navigation paradigm and therefore:</p>
2788
2789<ul>
2790 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2791Back functions.</li>
2792 <li>Android Television device implementations MUST provide the Home and Back
2793functions.</li>
2794 <li>Android Watch device implementations MUST have the Home function available to
2795the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2796 <li>Android Automotive implementations MUST provide the Home function and MAY
2797provide Back and Recent functions.</li>
2798 <li>All other types of device implementations MUST provide the Home and Back
2799functions.</li>
2800</ul>
2801
2802<p>These functions MAY be implemented via dedicated physical buttons (such as
2803mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2804software keys on a distinct portion of the screen, gestures, touch panel, etc.
2805Android supports both implementations. All of these functions MUST be
2806accessible with a single action (e.g. tap, double-click or gesture) when
2807visible.</p>
2808
2809<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2810together with other navigation functions in full-screen mode. This does not
2811apply to devices upgrading from earlier Android versions that have physical
2812buttons for navigation and no recents key.</p>
2813
2814<p> The Home and Back functions, if provided, MUST each have a visible button or
2815icon unless hidden together with other navigation functions in full-screen mode
2816or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2817
2818<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2819Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2820implement a dedicated physical button for the Menu function. Older device
2821implementations SHOULD NOT implement a dedicated physical button for the Menu
2822function, but if the physical Menu button is implemented and the device is
2823running applications with targetSdkVersion > 10, the device implementation:</p>
2824
2825<ul>
2826 <li>MUST display the action overflow button on the action bar when it is visible
2827and the resulting action overflow menu popup is not empty. For a device
2828implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2829is RECOMMENDED.</li>
2830 <li>MUST NOT modify the position of the action overflow popup displayed by
2831selecting the overflow button in the action bar.</li>
2832 <li>MAY render the action overflow popup at a modified position on the screen when
2833it is displayed by selecting the physical menu button.</li>
2834</ul>
2835
2836<p>For backwards compatibility, device implementations MUST make the Menu function
2837available to applications when targetSdkVersion is less than 10, either by a physical
2838button, a software key, or gestures. This Menu function should be presented
2839unless hidden together with other navigation functions.</p>
2840
2841<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
2842the Assist action available to the user at all times when running applications.
2843The Assist action SHOULD be implemented as a long-press on the Home button or a
2844swipe-up gesture on the software Home key. This function MAY be implemented via
2845another physical button, software key, or gesture, but MUST be accessible with
2846a single action (e.g. tap, double-click, or gesture) when other navigation keys
2847are visible.</p>
2848
2849<p>Device implementations MAY use a distinct portion of the screen to display the
2850navigation keys, but if so, MUST meet these requirements:</p>
2851
2852<ul>
2853 <li>Device implementation navigation keys MUST use a distinct portion of the
2854screen, not available to applications, and MUST NOT obscure or otherwise
2855interfere with the portion of the screen available to applications.</li>
2856 <li>Device implementations MUST make available a portion of the display to
2857applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2858 <li>Device implementations MUST display the navigation keys when applications do
2859not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2860 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2861profile&rdquo; (eg. dimmed) mode when applications specify
2862SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2863 <li>Device implementations MUST hide the navigation keys when applications specify
2864SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2865</ul>
2866
2867<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2868
2869<div class="note">
2870<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2871</div>
2872
2873
2874<p>Device implementations SHOULD have a pointer input system of some kind (either
2875mouse-like or touch). However, if a device implementation does not support a
2876pointer input system, it MUST NOT report the android.hardware.touchscreen or
2877android.hardware.faketouch feature constant. Device implementations that do
2878include a pointer input system:</p>
2879
2880<ul>
2881 <li>SHOULD support fully independently tracked pointers, if the device input system
2882supports multiple pointers.</li>
2883 <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>
2884</ul>
2885
2886<p>Android includes support for a variety of touchscreens, touch pads, and fake
2887touch input devices. Touchscreen based device implementations are associated
2888with 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
2889screen. Since the user is directly touching the screen, the system does not
2890require any additional affordances to indicate the objects being manipulated.
2891In contrast, a fake touch interface provides a user input system that
2892approximates a subset of touchscreen capabilities. For example, a mouse or
2893remote control that drives an on-screen cursor approximates touch, but requires
2894the user to first point or focus then click. Numerous input devices like the
2895mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2896trackpad can support fake touch interactions. Android includes the feature
2897constant android.hardware.faketouch, which corresponds to a high-fidelity
2898non-touch (pointer-based) input device such as a mouse or trackpad that can
2899adequately emulate touch-based input (including basic gesture support), and
2900indicates that the device supports an emulated subset of touchscreen
2901functionality. Device implementations that declare the fake touch feature MUST
2902meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2903
2904<p>Device implementations MUST report the correct feature corresponding to the
2905type of input used. Device implementations that include a touchscreen
2906(single-touch or better) MUST report the platform feature constant
2907android.hardware.touchscreen. Device implementations that report the platform
2908feature constant android.hardware.touchscreen MUST also report the platform
2909feature constant android.hardware.faketouch. Device implementations that do not
2910include a touchscreen (and rely on a pointer device only) MUST NOT report any
2911touchscreen feature, and MUST report only android.hardware.faketouch if they
2912meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2913
2914<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2915
2916
2917<p>Device implementations that declare support for android.hardware.faketouch:</p>
2918
2919<ul>
2920 <li>MUST report the absolute X and Y screen positions of the pointer location and
2921display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2922 <li>MUST report touch event with the action code that specifies the state change
2923that 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>
2924 <li>MUST support pointer down and up on an object on the screen, which allows users
2925to emulate tap on an object on the screen.</li>
2926 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2927place on an object on the screen within a time threshold, which allows users to
2928emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2929 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2930any other arbitrary point on the screen, followed by a pointer up, which allows
2931users to emulate a touch drag.</li>
2932 <li>MUST support pointer down then allow users to quickly move the object to a
2933different position on the screen and then pointer up on the screen, which
2934allows users to fling an object on the screen.</li>
2935</ul>
2936
2937<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2938MUST meet the requirements for faketouch above, and MUST also support distinct
2939tracking of two or more independent pointer inputs.</p>
2940
2941<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
2942
2943
2944<p>Android Television device implementations MUST support button mappings for game
2945controllers as listed below. The upstream Android implementation includes
2946implementation for game controllers that satisfies this requirement. </p>
2947
2948<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
2949
2950
2951<p>Android Television device implementations MUST support the following key
2952mappings:</p>
2953<table>
2954 <tr>
2955 <th>Button</th>
2956 <th>HID Usage</strong><sup>2</sup></td>
2957 <th>Android Button</th>
2958 </tr>
2959 <tr>
2960 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
2961 <td>0x09 0x0001</td>
2962 <td>KEYCODE_BUTTON_A (96)</td>
2963 </tr>
2964 <tr>
2965 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
2966 <td>0x09 0x0002</td>
2967 <td>KEYCODE_BUTTON_B (97)</td>
2968 </tr>
2969 <tr>
2970 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
2971 <td>0x09 0x0004</td>
2972 <td>KEYCODE_BUTTON_X (99)</td>
2973 </tr>
2974 <tr>
2975 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
2976 <td>0x09 0x0005</td>
2977 <td>KEYCODE_BUTTON_Y (100)</td>
2978 </tr>
2979 <tr>
2980 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
2981
2982<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]2983 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2984 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
2985 </tr>
2986 <tr>
2987 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
2988
2989<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]2990 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2991 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
2992 </tr>
2993 <tr>
2994 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
2995 <td>0x09 0x0007</td>
2996 <td>KEYCODE_BUTTON_L1 (102)</td>
2997 </tr>
2998 <tr>
2999 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3000 <td>0x09 0x0008</td>
3001 <td>KEYCODE_BUTTON_R1 (103)</td>
3002 </tr>
3003 <tr>
3004 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3005 <td>0x09 0x000E</td>
3006 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3007 </tr>
3008 <tr>
3009 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3010 <td>0x09 0x000F</td>
3011 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3012 </tr>
3013 <tr>
3014 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3015 <td>0x0c 0x0223</td>
3016 <td>KEYCODE_HOME (3)</td>
3017 </tr>
3018 <tr>
3019 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3020 <td>0x0c 0x0224</td>
3021 <td>KEYCODE_BACK (4)</td>
3022 </tr>
3023</table>
3024
3025
3026<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3027
3028<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3029
3030<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3031Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3032Report Size of 4. The logical value is defined to be the clockwise rotation
3033away from the vertical axis; for example, a logical value of 0 represents no
3034rotation and the up button being pressed, while a logical value of 1 represents
3035a rotation of 45 degrees and both the up and left keys being pressed.</p>
3036
3037<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3038
3039<table>
3040 <tr>
3041 <th>Analog Controls</strong><sup>1</sup></td>
3042 <th>HID Usage</th>
3043 <th>Android Button</th>
3044 </tr>
3045 <tr>
3046 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3047 <td>0x02 0x00C5</td>
3048 <td>AXIS_LTRIGGER </td>
3049 </tr>
3050 <tr>
3051 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3052 <td>0x02 0x00C4</td>
3053 <td>AXIS_RTRIGGER </td>
3054 </tr>
3055 <tr>
3056 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3057 <td>0x01 0x0030</p>
3058
3059<p>0x01 0x0031</td>
3060 <td>AXIS_X</p>
3061
3062<p>AXIS_Y</td>
3063 </tr>
3064 <tr>
3065 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3066 <td>0x01 0x0032</p>
3067
3068<p>0x01 0x0035</td>
3069 <td>AXIS_Z</p>
3070
3071<p>AXIS_RZ</td>
3072 </tr>
3073</table>
3074
3075
3076<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3077
3078<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3079
3080
3081<p>Android Television device implementations SHOULD provide a remote control to
3082allow users to access the TV interface. The remote control MAY be a physical
3083remote or can be a software-based remote that is accessible from a mobile phone
3084or tablet. The remote control MUST meet the requirements defined below.</p>
3085
3086<ul>
3087 <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>
3088 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3089support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3090</ul>
3091
3092<h2 id="7_3_sensors">7.3. Sensors</h2>
3093
3094
3095<p>Android includes APIs for accessing a variety of sensor types. Devices
3096implementations generally MAY omit these sensors, as provided for in the
3097following subsections. If a device includes a particular sensor type that has a
3098corresponding API for third-party developers, the device implementation MUST
3099implement that API as described in the Android SDK documentation and the
3100Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3101
3102<ul>
3103 <li>MUST accurately report the presence or absence of sensors per the
3104android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3105 <li>MUST return an accurate list of supported sensors via the
3106SensorManager.getSensorList() and similar methods.</li>
3107 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3108true or false as appropriate when applications attempt to register listeners,
3109not calling sensor listeners when the corresponding sensors are not present;
3110etc.).</li>
3111 <li>MUST report all sensor measurements using the relevant International System of
3112Units (metric) values for each sensor type as defined in the Android SDK
3113documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3114 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3115documentation, representing the time the event happened and synchronized with
3116the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3117are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3118platform releases where this might become a REQUIRED component. The
3119synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3120</ul>
3121
3122<p>The list above is not comprehensive; the documented behavior of the Android SDK
3123and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3124
3125<p>Some sensor types are composite, meaning they can be derived from data provided
3126by one or more other sensors. (Examples include the orientation sensor, and the
3127linear acceleration sensor.) Device implementations SHOULD implement these
3128sensor types, when they include the prerequisite physical sensors as described
3129in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3130If a device implementation includes a composite sensor it MUST implement the
3131sensor as described in the Android Open Source documentation on composite
3132sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3133
3134<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3135continuously [<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
3136sensor, device implementations MUST continuously provide periodic data samples
3137that SHOULD have a jitter below 3%, where jitter is defined as the standard
3138deviation of the difference of the reported timestamp values between
3139consecutive events.</p>
3140
3141<p>Note that the device implementations MUST ensure that the sensor event stream
3142MUST NOT prevent the device CPU from entering a suspend state or waking up from
3143a suspend state.</p>
3144
3145<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3146exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3147
3148<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3149
3150
3151<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3152devices and Android Watch devices are strongly encouraged to include this
3153sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3154
3155<ul>
3156 <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>
3157 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3158 Android Watch devices as such devices have a stricter power constraint and
3159 100 Hz for all other device types.</li>
3160 <li>SHOULD report events up to at least 200 Hz.</li>
3161 <li>MUST comply with the Android sensor coordinate system as detailed in the
3162Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3163 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3164more on any axis.</li>
3165 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3166least 16-bits.</li>
3167 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3168cycle and compensated, and preserve the compensation parameters between device
3169reboots.</li>
3170 <li>SHOULD be temperature compensated.</li>
3171 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3172deviation should be calculated on a per axis basis on samples collected over a
3173period of at least 3 seconds at the fastest sampling rate.</li>
3174 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3175TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3176Android 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
3177sensors are implemented, the sum of their power consumption MUST always be less
3178than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3179dynamic or static condition.</li>
3180 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3181TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3182TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3183are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3184 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3185and a magnetometer sensor is also included.</li>
3186</ul>
3187
3188<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3189
3190
3191<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3192device does include a 3-axis magnetometer, it:</p>
3193
3194<ul>
3195 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3196TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3197strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3198 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3199report events up to at least 50 Hz.</li>
3200 <li>MUST comply with the Android sensor coordinate system as detailed in the
3201Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3202 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3203saturating.</li>
3204 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3205below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3206and static (magnet-induced) magnetic fields.</li>
3207 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3208equal or denser than 0.2 &micro;.</li>
3209 <li>SHOULD be temperature compensated.</li>
3210 <li>MUST support online calibration and compensation of the hard iron bias, and
3211preserve the compensation parameters between device reboots.</li>
3212 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3213while in use or during the production of the device.</li>
3214 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3215collected over a period of at least 3 seconds at the fastest sampling rate, no
3216greater than 0.5 &micro;T.</li>
3217 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3218sensor and a gyroscope sensor is also included.</li>
3219 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3220sensor is also implemented. However if implemented, it MUST consume less than
322110 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3222mode at 10 Hz.</li>
3223</ul>
3224
3225<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3226
3227
3228<p>Device implementations SHOULD include a GPS receiver. If a device
3229implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3230
3231<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3232
3233
3234<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3235Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3236also included. If a device implementation includes a gyroscope, it:</p>
3237
3238<ul>
3239 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3240TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3241strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3242 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3243 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3244 Android Watch devices as such devices have a stricter power constraint and
3245 100 Hz for all other device types.</li>
3246 <li>SHOULD report events up to at least 200 Hz.</li>
3247 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
324816-bits or more.</li>
3249 <li>MUST be temperature compensated.</li>
3250 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3251parameters between device reboots.</li>
3252 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3253or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3254be constrained by this value. In other words, if you measure the variance of
3255the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3256 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3257sensor and a magnetometer sensor is also included.</li>
3258 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3259TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3260TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3261are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3262</ul>
3263
3264<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3265
3266
3267<p>Device implementations SHOULD include a barometer (ambient air pressure
3268sensor). If a device implementation includes a barometer, it:</p>
3269
3270<ul>
3271 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3272 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3273 <li>MUST have adequate precision to enable estimating altitude.</li>
3274 <li>MUST be temperature compensated.</li>
3275</ul>
3276
3277<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3278
3279
3280<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3281If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3282measure the ambient (room) temperature in degrees Celsius.</p>
3283
3284<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3285present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3286temperature of the device CPU, and it MUST NOT measure any other temperature.
3287Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3288
3289<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3290
3291
3292<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3293
3294<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3295
3296
3297<p>Device implementations MAY include a proximity sensor. Devices that can make a
3298voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3299SHOULD include a proximity sensor. If a device implementation does include a
3300proximity sensor, it:</p>
3301
3302<ul>
3303 <li>MUST measure the proximity of an object in the same direction as the screen.
3304That is, the proximity sensor MUST be oriented to detect objects close to the
3305screen, as the primary intent of this sensor type is to detect a phone in use
3306by the user. If a device implementation includes a proximity sensor with any
3307other orientation, it MUST NOT be accessible through this API.</li>
3308 <li>MUST have 1-bit of accuracy or more.</li>
3309</ul>
3310
3311<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3312
3313
3314<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3315
3316
3317<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3318to hardware related to placing voice calls and sending SMS messages via a GSM
3319or CDMA network. While these voice calls may or may not be packet-switched,
3320they are for the purposes of Android considered independent of any data
3321connectivity that may be implemented using the same network. In other words,
3322the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3323calls and SMS. For instance, device implementations that cannot place calls or
3324send/receive SMS messages MUST NOT report the android.hardware.telephony
3325feature or any subfeatures, regardless of whether they use a cellular network
3326for data connectivity.</p>
3327
3328<p>Android MAY be used on devices that do not include telephony hardware. That is,
3329Android is compatible with devices that are not phones. However, if a device
3330implementation does include GSM or CDMA telephony, it MUST implement full
3331support for the API for that technology. Device implementations that do not
3332include telephony hardware MUST implement the full APIs as no-ops.</p>
3333
3334<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3335
3336<div class="note">
3337<p>Android Television device implementations MUST include Wi-Fi support.</p>
3338</div>
3339
3340
3341<p>Android Television device implementations MUST include support for one or more
3342forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3343implementation SHOULD include support for one or more forms of 802.11. If a
3344device implementation does include support for 802.11 and exposes the
3345functionality to a third-party application, it MUST implement the corresponding
3346Android API and:</p>
3347
3348<ul>
3349 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3350 <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>
3351 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3352(224.0.0.251) at any time of operation including when the screen is not in an
3353active state.</li>
3354</ul>
3355
3356<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3357
3358
3359<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3360peer-to-peer). If a device implementation does include support for Wi-Fi
3361Direct, it MUST implement the corresponding Android API as described in the SDK
3362documentation [<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>
3363
3364<ul>
3365 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3366 <li>MUST support regular Wi-Fi operation.</li>
3367 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3368</ul>
3369
3370<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3371
3372<div class="note">
3373<p>Android Television device implementations MUST include support for Wi-Fi
3374Tunneled Direct Link Setup (TDLS).</p>
3375</div>
3376
3377
3378<p>Android Television device implementations MUST include support for Wi-Fi
3379Tunneled Direct Link Setup (TDLS) and other types of Android device
3380implementations SHOULD include support for Wi-Fi TDLS as described in the
3381Android 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
3382by the WiFiManager API, the device:</p>
3383
3384<ul>
3385 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3386 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3387than going through the Wi-Fi access point.</li>
3388</ul>
3389
3390<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3391
3392<div class="note">
3393<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3394Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3395</div>
3396
3397
3398<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
3399Energy MUST declare the relevant platform features (android.hardware.bluetooth
3400and android.hardware.bluetooth_le respectively) and implement the platform
3401APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3402as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3403device implementations MUST support Bluetooth and Bluetooth LE. </p>
3404
3405<p>Device implementations including support for Bluetooth Low Energy:</p>
3406
3407<ul>
3408 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3409 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3410described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3411 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3412implementing 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
3413android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3414 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3415if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3416android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3417 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3418MUST report &lsquo;false&rsquo; whenever queried via the
3419android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3420</ul>
3421
3422<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3423
3424
3425<p>Device implementations SHOULD include a transceiver and related hardware for
3426Near-Field Communications (NFC). If a device implementation does include NFC
3427hardware and plans to make it available to third-party apps, then it:</p>
3428
3429<ul>
3430 <li>MUST report the android.hardware.nfc feature from the
3431android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3432 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3433standards:
3434 <ul>
3435 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3436Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3437following NFC standards:
3438 <ul>
3439 <li>NfcA (ISO14443-3A)</li>
3440 <li>NfcB (ISO14443-3B)</li>
3441 <li>NfcF (JIS 6319-4)</li>
3442 <li>IsoDep (ISO 14443-4)</li>
3443 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3444 </ul>
3445 <li>SHOULD be capable of reading and writing NDEF messages via the following NFC
3446standards. Note that while the NFC standards below are stated as SHOULD, the
3447Compatibility Definition for a future version is planned to change these to
3448MUST. These standards are optional in this version but will be required in
3449future 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>
3450 <ul>
3451 <li>NfcV (ISO 15693)</li>
3452 </ul></li>
3453 <li>MUST be capable of transmitting and receiving data via the following
3454peer-to-peer standards and protocols:
3455 <ul>
3456 <li>ISO 18092</li>
3457 <li>LLCP 1.0 (defined by the NFC Forum)</li>
3458 <li>SDP 1.0 (defined by the NFC Forum)</li>
3459 <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>
3460 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3461 </ul></li>
3462 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3463 <ul>
3464 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3465default SNEP server MUST be dispatched to applications using the
3466android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3467MUST NOT disable dispatch of incoming NDEF message.</li>
3468 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3469settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3470 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3471processed the same way as the SNEP default server.</li>
3472 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3473default SNEP server when Android Beam is enabled. If no default SNEP server is
3474found then the client MUST attempt to send to an NPP server.</li>
3475 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3476android.nfc.NfcAdapter.setNdefPushMessage, and
3477android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3478android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3479 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3480sending outbound P2P NDEF messages.</li>
3481 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3482using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3483 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3484Bluetooth Object Push Profile. Device implementations MUST support connection
3485handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3486implementing 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
3487LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3488handover request/select records over NFC, and it MUST use the Bluetooth Object
3489Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3490remain compatible with Android 4.1 devices), the implementation SHOULD still
3491accept SNEP GET requests for exchanging the handover request/select records
3492over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3493for performing connection handover.</li>
3494 </ul></li>
3495 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3496 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3497active and the lock-screen unlocked.</li>
3498</ul>
3499</ul>
3500
3501<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3502Forum specifications cited above.)</p>
3503
3504<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3505device implementation does include an NFC controller chipset capable of HCE and
3506Application ID (AID) routing, then it:</p>
3507
3508<ul>
3509 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3510 <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>
3511</ul>
3512
3513<p>Additionally, device implementations MAY include reader/writer support for the
3514following MIFARE technologies.</p>
3515
3516<ul>
3517 <li>MIFARE Classic</li>
3518 <li>MIFARE Ultralight</li>
3519 <li>NDEF on MIFARE Classic</li>
3520</ul>
3521
3522<p>Note that Android includes APIs for these MIFARE types. If a device
3523implementation supports MIFARE in the reader/writer role, it:</p>
3524
3525<ul>
3526 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3527 <li>MUST report the feature com.nxp.mifare from the
3528android.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
3529as a constant on the PackageManager class.</li>
3530 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3531feature unless it also implements general NFC support as described in this
3532section.</li>
3533</ul>
3534
3535<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3536the android.hardware.nfc feature from the
3537android.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>
3538
3539<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3540protocol-independent data representation format, device implementations MUST
3541implement these APIs even if they do not include support for NFC or declare the
3542android.hardware.nfc feature.</p>
3543
3544<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3545
3546
3547<p>Device implementations MUST include support for one or more forms of data
3548networking. Specifically, device implementations MUST include support for at
3549least one data standard capable of 200Kbit/sec or greater. Examples of
3550technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3551Ethernet, Bluetooth PAN, etc.</p>
3552
3553<p>Device implementations where a physical networking standard (such as Ethernet)
3554is the primary data connection SHOULD also include support for at least one
3555common wireless data standard, such as 802.11 (Wi-Fi).</p>
3556
3557<p>Devices MAY implement more than one form of data connectivity.</p>
3558
3559<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3560
3561
3562<p>Device implementations MUST have the master auto-sync setting on by default so
3563that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3564
3565<h2 id="7_5_cameras">7.5. Cameras</h2>
3566
3567
3568<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3569front-facing camera. A rear-facing camera is a camera located on the side of
3570the device opposite the display; that is, it images scenes on the far side of
3571the device, like a traditional camera. A front-facing camera is a camera
3572located on the same side of the device as the display; that is, a camera
3573typically used to image the user, such as for video conferencing and similar
3574applications.</p>
3575
3576<p>If a device implementation includes at least one camera, it SHOULD be possible
3577for an application to simultaneously allocate 3 bitmaps equal to the size of
3578the images produced by the largest-resolution camera sensor on the device.</p>
3579
3580<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3581
3582
3583<p>Device implementations SHOULD include a rear-facing camera. If a device
3584implementation includes at least one rear-facing camera, it:</p>
3585
3586<ul>
3587 <li>MUST report the feature flag android.hardware.camera and
3588android.hardware.camera.any.</li>
3589 <li>MUST have a resolution of at least 2 megapixels.</li>
3590 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3591the camera driver (transparent to application software).</li>
3592 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3593 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3594lit while an android.hardware.Camera.PreviewCallback instance has been
3595registered on a Camera preview surface, unless the application has explicitly
3596enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3597of a Camera.Parameters object. Note that this constraint does not apply to the
3598device&rsquo;s built-in system camera application, but only to third-party
3599applications using Camera.PreviewCallback.</li>
3600</ul>
3601
3602<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3603
3604
3605<p>Device implementations MAY include a front-facing camera. If a device
3606implementation includes at least one front-facing camera, it:</p>
3607
3608<ul>
3609 <li>MUST report the feature flag android.hardware.camera.any and
3610android.hardware.camera.front.</li>
3611 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3612 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3613camera API in Android has specific support for front-facing cameras and device
3614implementations MUST NOT configure the API to to treat a front-facing camera as
3615the default rear-facing camera, even if it is the only camera on the device.</li>
3616 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3617cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3618 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3619CameraPreview, as follows:
3620 <ul>
3621 <li>If the device implementation is capable of being rotated by user (such as
3622automatically via an accelerometer or manually via user input), the camera
3623preview MUST be mirrored horizontally relative to the device&rsquo;s current
3624orientation.</li>
3625 <li>If the current application has explicitly requested that the Camera display be
3626rotated 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
3627orientation specified by the application.</li>
3628 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3629axis.</li>
3630 </ul></li>
3631 <li>MUST mirror the image displayed by the postview in the same manner as the
3632camera preview image stream. If the device implementation does not support
3633postview, this requirement obviously does not apply.</li>
3634 <li>MUST NOT mirror the final captured still image or video streams returned to
3635application callbacks or committed to media storage.</li>
3636</ul>
3637
3638<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3639
3640
3641<p>Device implementations with USB host mode MAY include support for an external
3642camera that connects to the USB port. If a device includes support for an
3643external camera, it:</p>
3644
3645<ul>
3646 <li>MUST declare the platform feature android.hardware.camera.external and
3647android.hardware camera.any.</li>
3648 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3649 <li>MAY support multiple cameras.</li>
3650</ul>
3651
3652<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3653high-quality unencoded streams (i.e. raw or independently compressed picture
3654streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3655unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3656device implementation.</p>
3657
3658<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3659
3660
3661<p>Android includes two API packages to access the camera, the newer
3662android.hardware.camera2 API expose lower-level camera control to the app,
3663including efficient zero-copy burst/streaming flows and per-frame controls of
3664exposure, gain, white balance gains, color conversion, denoising, sharpening,
3665and more.</p>
3666
3667<p>The older API package, android.hardware.Camera, is marked as deprecated in
3668Android 5.0 but as it should still be available for apps to use Android device
3669implementations MUST ensure the continued support of the API as described in
3670this section and in the Android SDK.</p>
3671
3672<p>Device implementations MUST implement the following behaviors for the
3673camera-related APIs, for all available cameras:</p>
3674
3675<ul>
3676 <li>If an application has never called
3677android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3678use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3679application callbacks.</li>
3680 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3681and the system calls the onPreviewFrame() method when the preview format is
3682YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3683be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3684 <li>For android.hardware.Camera, device implementations MUST support the YV12
3685format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3686camera previews for both front- and rear-facing cameras. (The hardware video
3687encoder and camera may use any native pixel format, but the device
3688implementation MUST support conversion to YV12.)</li>
3689 <li>For android.hardware.camera2, device implementations must support the
3690android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3691formats as outputs through the android.media.ImageReader API.</li>
3692</ul>
3693
3694<p>Device implementations MUST still implement the full Camera API included in the
3695Android 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
3696capabilities. For instance, cameras that lack autofocus MUST still call any
3697registered android.hardware.Camera.AutoFocusCallback instances (even though
3698this has no relevance to a non-autofocus camera.) Note that this does apply to
3699front-facing cameras; for instance, even though most front-facing cameras do
3700not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3701
3702<p>Device implementations MUST recognize and honor each parameter name defined as
3703a constant on the android.hardware.Camera.Parameters class, if the underlying
3704hardware supports the feature. If the device hardware does not support a
3705feature, the API must behave as documented. Conversely, device implementations
3706MUST NOT honor or recognize string constants passed to the
3707android.hardware.Camera.setParameters() method other than those documented as
3708constants on the android.hardware.Camera.Parameters. That is, device
3709implementations MUST support all standard Camera parameters if the hardware
3710allows, and MUST NOT support custom Camera parameter types. For instance,
3711device implementations that support image capture using high dynamic range
3712(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>
3713
3714<p>Because not all device implementations can fully support all the features of
3715the android.hardware.camera2 API, device implementations MUST report the proper
3716level of support with the android.info.supportedHardwareLevel property as
3717described 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>
3718
3719<p>Device implementations MUST also declare its Individual camera capabilities of
3720android.hardware.camera2 via the android.request.availableCapabilities property
3721and 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>
3722
3723<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3724whenever a new picture is taken by the camera and the entry of the picture has
3725been added to the media store.</p>
3726
3727<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3728whenever a new video is recorded by the camera and the entry of the picture has
3729been added to the media store.</p>
3730
3731<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3732
3733
3734<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3735long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3736when the device is held in the landscape orientation, cameras MUST capture
3737images in the landscape orientation. This applies regardless of the device&rsquo;s
3738natural orientation; that is, it applies to landscape-primary devices as well
3739as portrait-primary devices.</p>
3740
3741<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3742
3743
3744<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3745
3746<div class="note">
3747<p>Android Television devices MUST have at least 5GB of non-volatile storage
3748available for application private data.</p>
3749</div>
3750
3751
3752<p>The memory available to the kernel and userspace on device implementations MUST
3753be at least equal or larger than the minimum values specified by the following
3754table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3755<table>
3756 <tr>
3757 <th>Density and screen size</th>
3758 <th>32-bit device</th>
3759 <th>64-bit device</th>
3760 </tr>
3761 <tr>
3762 <td>Android Watch devices (due to smaller screens)</td>
3763 <td>416MB</td>
3764 <td>Not applicable</td>
3765 </tr>
3766 <tr>
3767 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3768 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3769 <li class="table_list">mdpi or lower on large screens</li>
3770 <li class="table_list">ldpi or lower on extra large screens</li>
3771 </ul></td>
3772 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3773 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3774 </tr>
3775 <tr>
3776 <td><ul>
3777 <li class="table_list">xhdpi or higher on small/normal screens</li>
3778 <li class="table_list">hdpi or higher on large screens</li>
3779 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3780 <td>512MB</td>
3781 <td>832MB</td>
3782 </tr>
3783 <tr>
3784 <td><ul>
3785 <li class="table_list">400dpi or higher on small/normal screens</li>
3786 <li class="table_list">xhdpi or higher on large screens</li>
3787 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3788 <td>896MB</td>
3789 <td>1280MB</td>
3790 </tr>
3791 <tr>
3792 <td><ul>
3793 <li class="table_list">560dpi or higher on small/normal screens</li>
3794 <li class="table_list">400dpi or higher on large screens</li>
3795 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3796 <td>1344MB</td>
3797 <td>1824MB</td>
3798 </tr>
3799</table>
3800
3801
3802<p>The minimum memory values MUST be in addition to any memory space already
3803dedicated to hardware components such as radio, video, and so on that is not
3804under the kernel&rsquo;s control.</p>
3805
3806<p>Device implementations with less than 512MB of memory available to the kernel
3807and userspace, unless an Android Watch, MUST return the value "true" for
3808ActivityManager.isLowRamDevice().</p>
3809
3810<p>Android Television devices MUST have at least 5GB and other device
3811implementations MUST have at least 1.5GB of non-volatile storage available for
3812application private data. That is, the /data partition MUST be at least 5GB for
3813Android Television devices and at least 1.5GB for other device implementations.
3814Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3815they will be able to upgrade to the future platform releases.</p>
3816
3817<p>The Android APIs include a Download Manager that applications MAY use to
3818download 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
3819downloading individual files of at least 100MB in size to the default &ldquo;cache"
3820location.</p>
3821
3822<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3823
3824
3825<p>Device implementations MUST offer shared storage for applications also often
3826referred as &ldquo;shared external storage&rdquo;. </p>
3827
3828<p>Device implementations MUST be configured with shared storage mounted by
3829default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3830path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3831to the actual mount point.</p>
3832
3833<p>Device implementations MAY have hardware for user-accessible removable storage,
3834such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3835shared storage requirement, the device implementation:</p>
3836
3837<ul>
3838 <li>MUST implement a toast or pop-up user interface warning the user when there is
3839no SD card.</li>
3840 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3841and other material available at time of purchase that the SD card has to be
3842separately purchased.</li>
3843 <li>MUST mount the SD card by default.</li>
3844</ul>
3845
3846<p>Alternatively, device implementations MAY allocate internal (non-removable)
3847storage as shared storage for apps as included in the upstream Android Open
3848Source Project; device implementations SHOULD use this configuration and
3849software implementation. If a device implementation uses internal
3850(non-removable) storage to satisfy the shared storage requirement, that storage
3851MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3852symbolic link to the physical location if it is mounted elsewhere).</p>
3853
3854<p>Device implementations MUST enforce as documented the
3855android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3856Shared storage MUST otherwise be writable by any application that obtains that
3857permission.</p>
3858
3859<p>Device implementations that include multiple shared storage paths (such as both
3860an SD card slot and shared internal storage) MUST NOT allow Android
3861applications to write to the secondary external storage, except for their
3862package-specific directories on the secondary external storage, but SHOULD
3863expose content from both storage paths transparently through Android&rsquo;s media
3864scanner service and android.provider.MediaStore.</p>
3865
3866<p>Regardless of the form of shared storage used, if the device implementation
3867has a USB port with USB peripheral mode support, it MUST provide some mechanism
3868to access the contents of shared storage from a host computer. Device
3869implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3870to satisfy this requirement. If the device implementation supports Media
3871Transfer Protocol, it:</p>
3872
3873<ul>
3874 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3875[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3876 <li>SHOULD report a USB device class of 0x00.</li>
3877 <li>SHOULD report a USB interface name of 'MTP'.</li>
3878</ul>
3879
3880<h2 id="7_7_usb">7.7. USB</h2>
3881
3882
3883<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3884USB host mode.</p>
3885
3886<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3887
3888<ul>
3889 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3890-C USB port.</li>
3891 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3892new 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>
3893 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3894SHOULD either locate the port on the bottom of the device (according to natural
3895orientation) or enable software screen rotation for all apps (including home
3896screen), so that the display draws correctly when the device is oriented with
3897the 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>
3898 <li>It MUST allow a USB host connected with the Android device to access the
3899contents of the shared storage volume using either USB mass storage or Media
3900Transfer Protocol.</li>
3901 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3902documented in the Android SDK documentation, and if it is an Android Handheld
3903device it MUST implement the AOA API. Device implementations implementing the
3904AOA specification:
3905 <ul>
3906 <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>
3907 <li>MUST implement the USB audio class as documented in the Android SDK
3908documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3909 </ul></li>
3910 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3911as 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>
3912 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3913the value of android.os.Build.SERIAL.</li>
3914</ul>
3915
3916<p>If a device implementation includes a USB port supporting host mode, it:</p>
3917
3918<ul>
3919 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3920 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3921cables adapting the port to a standard type-A or type-C USB port.</li>
3922 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3923adapting the port to a standard type-A or type-C USB port.</li>
3924 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3925documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3926 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3927MUST 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>
3928 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3929as 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>
3930</ul>
3931
3932<h2 id="7_8_audio">7.8. Audio</h2>
3933
3934
3935<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3936
3937<div class="note">
3938<p>Android Handheld, Watch, and Automotive implementations MUST include a
3939microphone.</p>
3940</div>
3941
3942
3943<p>Device implementations MAY omit a microphone. However, if a device
3944implementation omits a microphone, it MUST NOT report the
3945android.hardware.microphone feature constant, and MUST implement the audio
3946recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
3947
3948<ul>
3949 <li>MUST report the android.hardware.microphone feature constant
3950 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
3951 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
3952</ul>
3953
3954<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
3955
3956<div class="note">
3957<p>Android Watch devices MAY include an audio output.</p>
3958</div>
3959
3960<p>Device implementations including a speaker or with an audio/multimedia output
3961port for an audio output peripheral as a headset or an external speaker:</p>
3962
3963<ul>
3964 <li>MUST report the android.hardware.audio.output feature constant.</li>
3965 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
3966 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
3967</ul>
3968
3969<p>Conversely, if a device implementation does not include a speaker or audio
3970output port, it MUST NOT report the android.hardware.audio output feature, and
3971MUST implement the Audio Output related APIs as no-ops at least. </p>
3972
3973<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
3974other types of Android device implementations MUST have an audio output and
3975declare android.hardware.audio.output.</p>
3976
3977<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
3978
3979
3980<p>In order to be compatible with the headsets and other audio accessories using
3981the 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
3982one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
3983implementation has a 4 conductor 3.5mm audio jack, it:</p>
3984
3985<ul>
3986 <li>MUST support audio playback to stereo headphones and stereo headsets with a
3987microphone, and SHOULD support audio recording from stereo headsets with a
3988microphone.</li>
3989 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
3990audio plugs with the OMTP pin-out order.</li>
3991 <li>MUST support the detection of microphone on the plugged in audio accessory, if
3992the device implementation supports a microphone, and broadcast the
3993android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
3994 <li>SHOULD support the detection and mapping to the keycodes for the following 3
3995ranges of equivalent impedance between the microphone and ground conductors on
3996the audio plug:
3997 <ul>
3998 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
3999 <li><strong>210&#45;290 Ohm</strong>:<strong> </strong>KEYCODE_VOLUME_UP</li>
4000 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4001 </ul></li>
4002 <li>SHOULD support the detection and mapping to the keycode for the following range
4003of equivalent impedance between the microphone and ground conductors on the
4004audio plug:
4005 <ul>
4006 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4007 </ul></li>
4008 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4009contacts on plug are touching their relevant segments on the jack.</li>
4010 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4011speaker impedance.</li>
4012 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4013</ul>
4014
4015<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4016
4017
4018<p>Some minimum performance criterias are critical to the user experience and
4019impacts the baseline assumptions developers would have when developing an app.
4020Android Watch devices SHOULD and other type of device implementations MUST meet
4021the following criteria:</p>
4022
4023<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4024
4025
4026<p>Device implementations MUST provide a smooth user interface by ensuring a
4027consistent frame rate and response times for applications and games. Device
4028implementations MUST meet the following requirements: </p>
4029
4030<ul>
4031 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4032often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4033 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4034list of 10K list entries as defined by the Android Compatibility Test Suite
4035(CTS) in less than 36 secs.</li>
4036 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4037application after it has been launched MUST take less than 1 second.</li>
4038</ul>
4039
4040<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4041
4042
4043<p>Device implementations MUST ensure internal storage file access performance consistency for read
4044and write operations. </p>
4045
4046<ul>
4047 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4048for a 256MB file using 10MB write buffer.</li>
4049 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4050256MB file using 4KB write buffer.</li>
4051 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4052a 256MB file using 10MB write buffer.</li>
4053 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4054256MB file using 4KB write buffer.</li>
4055</ul>
4056
4057<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4058
4059
4060<p>Device implementations MUST implement a security model consistent with the
4061Android platform security model as defined in Security and Permissions
4062reference 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
4063installation of self-signed applications without requiring any additional
4064permissions/certificates from any third parties/authorities. Specifically,
4065compatible devices MUST support the security mechanisms described in the follow
4066subsections.</p>
4067
4068<h2 id="9_1_permissions">9.1. Permissions</h2>
4069
4070
4071<p>Device implementations MUST support the Android permissions model as defined in
4072the 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
4073described in the SDK documentation; no permissions may be omitted, altered, or
4074ignored. Implementations MAY add additional permissions, provided the new
4075permission ID strings are not in the android.* namespace.</p>
4076
4077<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4078
4079
4080<p>Device implementations MUST support the Android application sandbox model, in
4081which each application runs as a unique Unixstyle UID and in a separate
4082process. Device implementations MUST support running multiple applications as
4083the same Linux user ID, provided that the applications are properly signed and
4084constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4085
4086<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4087
4088
4089<p>Device implementations MUST support the Android file access permissions model
4090as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4091
4092<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4093
4094
4095<p>Device implementations MAY include runtime environments that execute
4096applications using some other software or technology than the Dalvik Executable
4097Format or native code. However, such alternate execution environments MUST NOT
4098compromise the Android security model or the security of installed Android
4099applications, as described in this section.</p>
4100
4101<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4102standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4103
4104<p>Alternate runtimes MUST NOT be granted access to resources protected by
4105permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4106&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4107
4108<p>Alternate runtimes MUST NOT permit applications to make use of features
4109protected by Android permissions restricted to system applications.</p>
4110
4111<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4112alternate runtimes:</p>
4113
4114<ul>
4115 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4116Linux user IDs, etc.).</li>
4117 <li>MAY provide a single Android sandbox shared by all applications using the
4118alternate runtime.</li>
4119 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4120sandbox of any other app installed on the device, except through the standard
4121Android mechanisms of shared user ID and signing certificate.</li>
4122 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4123corresponding to other Android applications.</li>
4124 <li>MUST NOT be launched with, be granted, or grant to other applications any
4125privileges of the superuser (root), or of any other user ID.</li>
4126</ul>
4127
4128<p>The .apk files of alternate runtimes MAY be included in the system image of a
4129device implementation, but MUST be signed with a key distinct from the key used
4130to sign other applications included with the device implementation.</p>
4131
4132<p>When installing applications, alternate runtimes MUST obtain user consent for
4133the Android permissions used by the application. If an application needs to
4134make use of a device resource for which there is a corresponding Android
4135permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4136user that the application will be able to access that resource. If the runtime
4137environment does not record application capabilities in this manner, the
4138runtime environment MUST list all permissions held by the runtime itself when
4139installing any application using that runtime.</p>
4140
4141<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4142
4143<div class="note">
4144<p>This feature is optional for all device types.</p>
4145</div>
4146
4147
4148<p>Android includes support for multiple users and provides support for full user
4149isolation [<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
4150the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4151
4152<ul>
4153 <li>Device implementations that do not declare the android.hardware.telephony
4154feature flag MUST support restricted profiles, a feature that allows device
4155owners to manage additional users and their capabilities on the device. With
4156restricted profiles, device owners can quickly set up separate environments for
4157additional users to work in, with the ability to manage finer-grained
4158restrictions in the apps that are available in those environments.</li>
4159 <li>Conversely device implementations that declare the android.hardware.telephony
4160feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4161implementation of controls to enable /disable other users from accessing the
4162voice calls and SMS.</li>
4163 <li>Device implementations MUST, for each user, implement a security model
4164consistent with the Android platform security model as defined in Security and
4165Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4166 <li>Device implementations MAY support creating users and managed profiles via the
4167android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4168platform feature flag android.software.managed_users.
4169 <li>Device implementations that declare the feature flag
4170android.software.managed_users MUST use the upstream AOSP icon badge to
4171represent the managed applications and other badge UI elements like Recents &
4172Notifications.</li>
4173 <li>Each user instance on an Android device MUST have separate and isolated
4174external storage directories. Device implementations MAY store multiple users'
4175data on the same volume or filesystem. However, the device implementation MUST
4176ensure that applications owned by and running on behalf a given user cannot
4177list, read, or write to data owned by any other user. Note that removable
4178media, such as SD card slots, can allow one user to access another&rsquo;s data by
4179means of a host PC. For this reason, device implementations that use removable
4180media for the external storage APIs MUST encrypt the contents of the SD card if
4181multiuser is enabled using a key stored only on non-removable media accessible
4182only to the system. As this will make the media unreadable by a host PC, device
4183implementations will be required to switch to MTP or a similar system to
4184provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4185implementations MAY but SHOULD NOT enable multi-user if they use removable
4186media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4187</ul>
4188
4189<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4190
4191
4192<p>Android includes support for warning users of any outgoing premium SMS message
4193[<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
4194carrier that may incur a charge to the user. Device implementations that
4195declare support for android.hardware.telephony MUST warn users before sending a
4196SMS message to numbers identified by regular expressions defined in
4197/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4198Project provides an implementation that satisfies this requirement.</p>
4199
4200<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4201
4202
4203<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4204(SELinux) mandatory access control (MAC) system and other security features in
4205the Linux kernel. SELinux or any other security features, if implemented below
4206the Android framework:</p>
4207
4208<ul>
4209 <li>MUST maintain compatibility with existing applications.</li>
4210 <li>MUST NOT have a visible user interface when a security violation is detected
4211and successfully blocked, but MAY have a visible user interface when an
4212unblocked security violation occurs resulting in a successful exploit.</li>
4213 <li>SHOULD NOT be user or developer configurable.</li>
4214</ul>
4215
4216<p>If any API for configuration of policy is exposed to an application that can
4217affect another application (such as a Device Administration API), the API MUST
4218NOT allow configurations that break compatibility.</p>
4219
4220<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4221if using a kernel other than Linux and meet the following requirements, which
4222are satisfied by the reference implementation in the upstream Android Open
4223Source Project.</p>
4224
4225<p>Device implementations:</p>
4226
4227<ul>
4228 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4229per-domain basis, and MUST configure all domains in enforcing mode. No
4230permissive mode domains are allowed, including domains specific to a
4231device/vendor.</li>
4232 <li>SHOULD load policy from /sepolicy file on the device.</li>
4233 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4234sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4235the policy MUST compile with all neverallow present, for both AOSP SELinux
4236domains as well as device/vendor specific domains.</li>
4237 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4238system image update.</li>
4239</ul>
4240
4241<p>Device implementations SHOULD retain the default SELinux policy provided in the
4242upstream Android Open Source Project, until they have first audited their
4243additions to the SELinux policy. Device implementations MUST be compatible with
4244the upstream Android Open Source Project.</p>
4245
4246<h2 id="9_8_privacy">9.8. Privacy</h2>
4247
4248<p>If the device implements functionality in the system that captures the contents
4249displayed on the screen and/or records the audio stream played on the device,
4250it MUST continuously notify the user whenever this functionality is enabled and
4251actively capturing/recording.</p>
4252
4253<p>If a device implementation has a mechanism that routes network data traffic
4254through a proxy server or VPN gateway by default (for example, preloading a VPN
4255service with android.permission.CONTROL_VPN granted), the device implementation
4256MUST ask for the user's consent before enabling that mechanism.</p>
4257
4258<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4259
4260<div class="note">
4261<p>Optional for Android device implementations without a lock screen.</p>
4262</div>
4263
4264
4265<p>If the device implementation supports a lock screen with PIN (numeric) or
4266PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4267application private data (/data partition), as well
4268as the SD card partition if it is a permanent, non-removable part of the device
4269[<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
4270be enabled all the time after the user has completed the out-of-box experience.
4271While this requirement is stated as SHOULD for this version of the Android
4272platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4273Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4274for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4275be written to storage at any time without being encrypted. Other than when in
4276active use, the encryption key SHOULD be AES encrypted with the lockscreen
4277passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4278If the user has not specified a lockscreen passcode or has disabled use of the
4279passcode for encryption, the system SHOULD use a default passcode to wrap the
4280encryption key. If the device provides a hardware-backed keystore, the password
4281stretching algorithm MUST be cryptographically bound to that keystore. The
4282encryption key MUST NOT be sent off the device (even when wrapped with the user
4283passcode and/or hardware bound key). The upstream Android Open Source project
4284provides a preferred implementation of this feature based on the linux kernel
4285feature dm-crypt.</p>
4286
4287<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4288
4289<p>
4290Verified boot is a feature that guarantees the integrity of the device software.
4291If a device implementation supports the feature, it MUST:
4292<ul>
4293<li>Declare the platform feature flag android.software.verified_boot</li>
4294<li>Perform verification on every boot sequence</li>
4295<li>Start verification from a hardware key that is the root of trust, and go
4296all the way up to the system partition</li>
4297<li>Implement each stage of verification to check the integrity and authenticity
4298of all the bytes in the next stage before executing the code in the next stage</li>
4299<li>Use verification algorithms as strong as current recommendations
4300from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4301</ul>
4302</p>
4303
4304<p>Device implementations SHOULD support verified boot for device integrity.
4305While this requirement is SHOULD for this version of the Android platform,
4306it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4307in future versions of Android. The upstream Android Open Source Project provides
4308a preferred implementation of this feature based on the linux kernel feature dm-verity.
4309</p>
4310
4311<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4312
4313
4314<p>Device implementations MUST pass all tests described in this section.</p>
4315
4316<p>However, note that no software test package is fully comprehensive. For this
4317reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4318preferred implementation of Android available from the Android Open Source
4319Project. This will minimize the risk of introducing bugs that create
4320incompatibilities requiring rework and potential device updates.</p>
4321
4322<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4323
4324
4325<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
4326software on the device. Additionally, device implementers SHOULD use the
4327reference implementation in the Android Open Source tree as much as possible,
4328and MUST ensure compatibility in cases of ambiguity in CTS and for any
4329reimplementations of parts of the reference source code.</p>
4330
4331<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4332may itself contain bugs. The CTS will be versioned independently of this
4333Compatibility Definition, and multiple revisions of the CTS may be released for
4334Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4335at the time the device software is completed.</p>
4336
4337<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4338
4339
4340<p>Device implementations MUST correctly execute all applicable cases in the CTS
4341Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4342is intended to be run by a human operator to test functionality that cannot be
4343tested by an automated system, such as correct functioning of a camera and
4344sensors.</p>
4345
4346<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4347that is optional. Device implementations MUST pass all tests for hardware that
4348they possess; for instance, if a device possesses an accelerometer, it MUST
4349correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4350for features noted as optional by this Compatibility Definition Document MAY be
4351skipped or omitted.</p>
4352
4353<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4354above. However, since many builds are very similar, device implementers are not
4355expected to explicitly run the CTS Verifier on builds that differ only in
4356trivial ways. Specifically, device implementations that differ from an
4357implementation that has passed the CTS Verifier only by the set of included
4358locales, branding, etc. MAY omit the CTS Verifier test.</p>
4359
4360<h1 id="11_updatable_software">11. Updatable Software</h1>
4361
4362
4363<p>Device implementations MUST include a mechanism to replace the entirety of the
4364system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4365device restart MAY be required.</p>
4366
4367<p>Any method can be used, provided that it can replace the entirety of the
4368software preinstalled on the device. For instance, any of the following
4369approaches will satisfy this requirement:</p>
4370
4371<ul>
4372 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4373 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4374 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4375</ul>
4376
4377<p>However, if the device implementation includes support for an unmetered data
4378connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4379
4380<ul>
4381<li>Android Automotive implementations SHOULD support OTA downloads with offline
4382update via reboot.</li>
4383<li>All other device implementations MUST support OTA downloads with offline
4384update via reboot.</li>
4385</ul>
4386
4387<p>The update mechanism used MUST support updates without wiping user data. That
4388is, the update mechanism MUST preserve application private data and application
4389shared data. Note that the upstream Android software includes an update
4390mechanism that satisfies this requirement.</p>
4391
4392<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4393update mechanism SHOULD support verifying that the system image is binary
4394identical to expected result following an OTA. The block-based OTA
4395implementation in the upstream Android Open Source Project, added since Android
43965.1, satisfies this requirement.</p>
4397
4398<p>If an error is found in a device implementation after it has been released but
4399within its reasonable product lifetime that is determined in consultation with
4400the Android Compatibility Team to affect the compatibility of third-party
4401applications, the device implementer MUST correct the error via a software
4402update available that can be applied per the mechanism just described.</p>
4403
4404<h1 id="12_document_changelog">12. Document Changelog</h1>
4405
4406
4407<p>The following table contains a summary of the changes to the Compatibility
4408Definition in this release. </p>
4409<table>
4410 <tr>
4411 <th>Section</th>
4412 <th>Summary of change</th>
4413 </tr>
4414 <tr>
4415 <td>2. Device Types</td>
4416 <td>Added definition for Android automotive implementation.</td>
4417 </tr>
4418 <tr>
4419 <td>2.1 Device Configurations</td>
4420 <td>Added column for Android automotive implementation.</td>
4421 </tr>
4422 <tr>
4423 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4424 <td>New section added.</td>
4425 </tr>
4426 <tr>
4427 <td>3.4.1. WebView Compatibility</td>
4428 <td>Updated webview user agent string requirement to accomodate upstream
4429 implementation change.</td>
4430 </tr>
4431 <tr>
4432 <td>3.4.2. Browser compatibility</td>
4433 <td>Added Android automotive implementations as another case that MAY omit a
4434 browser application.</td>
4435 </tr>
4436 <tr>
4437 <td>3.7. Runtime Compatibility</td>
4438 <td>Updated required runtime heap size for smaller screens and added requirement
4439 for the new dpi bucket (280dpi).</td>
4440 </tr>
4441 <tr>
4442 <td>3.8.3. Notifications</td>
4443 <td>Clarified notification requirement for Android Watch, Television and
4444 Automotive implementations.</td>
4445 </tr>
4446 <tr>
4447 <td>3.8.10. Lock Screen Media Control<</td>
4448 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4449 </tr>
4450 <tr>
4451 <td>3.8.13. Unicode and font</td>
4452 <td>Relaxed Emoji character input method requirement.</td>
4453 </tr>
4454 <tr>
4455 <td>3.9. Device Administration</td>
4456 <td>Clarified condition when the full range of device administration policies
4457 has to be supported.</td>
4458 </tr>
4459 <tr>
4460 <td>3.10. Accessibility</td>
4461 <td>Added Android automotive requirements.</td>
4462 </tr>
4463 <tr>
4464 <td>3.11. Text-To-Speech</td>
4465 <td>Added Android automotive requirements.</td>
4466 </tr>
4467 <tr>
4468 <td>5.1. Media Codecs</td>
4469 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4470 </tr>
4471 <tr>
4472 <td>5.1.3 Video Codecs</td>
4473 <td>Added Android automotive requirements.</td>
4474 </tr>
4475 <tr>
4476 <td>7.1.1.3. Screen Density</td>
4477 <td>Added a new screen dpi (280dpi).</td>
4478 </tr>
4479 <tr>
4480 <td>7.1.5. Legacy Application Compatibility Mode</td>
4481 <td>Added Android automotive requirements.</td>
4482 </tr>
4483 <tr>
4484 <td>7.2 Input Devices</td>
4485 <td>Added general introduction statement.</td>
4486 </tr>
4487 <tr>
4488 <td>7.2.1. Keyboard</td>
4489 <td>Added Android Automotive requirements.</td>
4490 </tr>
4491 <tr>
4492 <td>7.2.3. Navigation Keys</td>
4493 <td>Added Android Automotive requirements.</td>
4494 </tr>
4495 <tr>
4496 <td>7.3.1. Accelerometer</td>
4497 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4498 </tr>
4499 <tr>
4500 <td>7.3.4. Gyroscope</td>
4501 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4502 </tr>
4503 <tr>
4504 <td>7.4.3 Bluetooth</td>
4505 <td>Added Android Automotive requirements.</td>
4506 </tr>
4507 <tr>
4508 <td>7.4.4. Near-Field Communications</td>
4509 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4510 </tr>
4511 <tr>
4512 <td>7.6.1. Minimum Memory and Storage</td>
4513 <td>Updated minimum memory requirements for lower resulution screen devices
4514 and added hard-limit requirement isLowRamDevice().</td>
4515 </tr>
4516 <tr>
4517 <td>7.6.2. Application Shared Storage</td>
4518 <td>Updated requirements when support for host machine access is mandatory.</td>
4519 </tr>
4520 <tr>
4521 <td>7.8.1. Microphone</td>
4522 <td>Added Android Automotive requirements.</td>
4523 </tr>
4524 <tr>
4525 <td>8.2. File I/O Access Performance</td>
4526 <td>Clarified requirements.</td>
4527 </tr>
4528 <tr>
4529 <td>9.8. Privacy</td>
4530 <td>Added privacy requirement for preloaded VPNs.</td>
4531 </tr>
4532 <tr>
4533 <td>9.9. Full-Disk Encryption</td>
4534 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4535 </tr>
4536 <tr>
4537 <td>9.10. Verified Boot</td>
4538 <td>Clarified definition of verified boot.</td>
4539 </tr>
4540 <tr>
4541 <td>11. Updatable Software</td>
4542 <td>Clarified the OTA download requirement is allowed but not mandatory for
4543 Android Automotive implementations.</td>
4544 </tr>
4545</table>
4546
4547
4548<h1 id="13_contact_us">13. Contact Us</h1>
4549
4550
4551<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
4552does not cover.</p>
4553
4554<h1 id="14_resources">14. Resources</h1>
4555
4556
4557<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4558
4559<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4560
4561<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>
4562
4563<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>
4564
4565<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4566
4567<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>
4568
4569<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>
4570
4571<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>
4572
4573<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>
4574
4575<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>
4576
4577<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>
4578
4579<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>
4580
4581<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4582
4583<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4584
4585<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>
4586
4587<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>
4588
4589<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4590
4591<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4592
4593<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4594
4595<p>20. Dalvik Executable Format and bytecode specification: available in the
4596Android source code, at dalvik/docs</p>
4597
4598<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>
4599
4600<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>
4601
4602<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>
4603
4604<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>
4605
4606<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4607
4608<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>
4609
4610<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>
4611
4612<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>
4613
4614<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>
4615
4616<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>
4617
4618<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>
4619
4620<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>
4621
4622<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>
4623
4624<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>
4625
4626<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>
4627
4628<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>
4629
4630<p>37. Settings.Secure LOCATION_MODE:</p>
4631
4632<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>
4633
4634<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>
4635
4636<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>
4637
4638<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>
4639
4640<p>41. Android Device Owner App:</p>
4641
4642<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>
4643
4644<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>
4645
4646<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>
4647
4648<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4649
4650<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>
4651
4652<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>
4653
4654<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>
4655
4656<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>
4657
4658<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>
4659
4660<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>
4661
4662<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>
4663
4664<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>
4665
4666<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4667
4668<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>
4669
4670<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>
4671
4672<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4673
4674<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4675
4676<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4677
4678<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>
4679
4680<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4681
4682<p>60. Android Application Development-Related Settings:</p>
4683
4684<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>
4685
4686<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>
4687
4688<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>
4689
4690<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4691
4692<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>
4693
4694<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>
4695
4696<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4697
4698<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>
4699
4700<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>
4701
4702<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>
4703
4704<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>
4705
4706<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>
4707
4708<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>
4709
4710<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>
4711
4712<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4713
4714<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>
4715
4716<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>
4717
4718<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>
4719
4720<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>
4721
4722<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>
4723
4724<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>
4725
4726<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>
4727
4728<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>
4729
4730<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>
4731
4732<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>
4733
4734<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>
4735
4736<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>
4737
4738<p>86. Android NFC Sharing Settings:</p>
4739
4740<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>
4741
4742<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>
4743
4744<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>
4745
4746<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>
4747
4748<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>
4749
4750<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>
4751
4752<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>
4753
4754<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>
4755
4756<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>
4757
4758<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>
4759
4760<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4761
4762<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>
4763
4764<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>
4765
4766<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>
4767
4768<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>
4769
4770<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>
4771
4772<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>
4773
4774<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>
4775
4776<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4777
4778<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>
4779
4780<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4781
4782<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>
4783
4784<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4785
4786<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>
4787
4788<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4789
4790<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>
4791
4792<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>
4793
4794<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>
4795
4796<p>Many of these resources are derived directly or indirectly from the Android
4797SDK, and will be functionally identical to the information in that SDK&rsquo;s
4798documentation. In any cases where this Compatibility Definition or the
4799Compatibility Test Suite disagrees with the SDK documentation, the SDK
4800documentation is considered authoritative. Any technical details provided in
4801the references included above are considered by inclusion to be part of this
4802Compatibility Definition.</p>
4803
4804</div>
4805</body>
4806</html>