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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
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]145<p class="toc_h2"><a href="#5_10_pro_audio">5.10. Professional Audio</a></p>
146
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]147<p class="toc_h1"><a href="#6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</a></p>
148
149<p class="toc_h2"><a href="#6_1_developer_tools">6.1. Developer Tools</a></p>
150
151<p class="toc_h2"><a href="#6_2_developer_options">6.2. Developer Options</a></p>
152
153<p class="toc_h1"><a href="#7_hardware_compatibility">7. Hardware Compatibility</a></p>
154
155<p class="toc_h2"><a href="#7_1_display_and_graphics">7.1. Display and Graphics</a></p>
156
157<p class="toc_h3"><a href="#7_1_1_screen_configuration">7.1.1. Screen Configuration</a></p>
158
159<p class="toc_h4"><a href="#7_1_1_1_screen_size">7.1.1.1. Screen Size</a></p>
160
161<p class="toc_h4"><a href="#7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</a></p>
162
163<p class="toc_h4"><a href="#7_1_1_3_screen_density">7.1.1.3. Screen Density</a></p>
164
165
166</div>
167
168<div style="clear: both; page-break-after:always; height:1px"></div>
169
170
171<div id="toc_left_2">
172
173<p class="toc_h3"><a href="#7_1_2_display_metrics">7.1.2. Display Metrics</a></p>
174
175<p class="toc_h3"><a href="#7_1_3_screen_orientation">7.1.3. Screen Orientation</a></p>
176
177<p class="toc_h3"><a href="#7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</a></p>
178
179<p class="toc_h3"><a href="#7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</a></p>
180
181<p class="toc_h3"><a href="#7_1_6_screen_technology">7.1.6. Screen Technology</a></p>
182
183<p class="toc_h3"><a href="#7_1_7_external_displays">7.1.7. Secondary Displays</a></p>
184
185<p class="toc_h2"><a href="#7_2_input_devices">7.2. Input Devices</a></p>
186
187<p class="toc_h3"><a href="#7_2_1_keyboard">7.2.1. Keyboard</a></p>
188
189<p class="toc_h3"><a href="#7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</a></p>
190
191<p class="toc_h3"><a href="#7_2_3_navigation_keys">7.2.3. Navigation Keys</a></p>
192
193<p class="toc_h3"><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen Input</a></p>
194
195<p class="toc_h3"><a href="#7_2_5_fake_touch_input">7.2.5. Fake Touch Input</a></p>
196
197<p class="toc_h3"><a href="#7_2_6_game_controller_support">7.2.6. Game Controller Support</a></p>
198
199<p class="toc_h4"><a href="#7_2_6_1_button_mapping">7.2.6.1. Button Mappings</a></p>
200
201<p class="toc_h3"><a href="#7_2_7_remote_control">7.2.7. Remote Control</a></p>
202
203<p class="toc_h2"><a href="#7_3_sensors">7.3. Sensors</a></p>
204
205<p class="toc_h3"><a href="#7_3_1_accelerometer">7.3.1. Accelerometer</a></p>
206
207<p class="toc_h3"><a href="#7_3_2_magnetometer">7.3.2. Magnetometer</a></p>
208
209<p class="toc_h3"><a href="#7_3_3_gps">7.3.3. GPS</a></p>
210
211<p class="toc_h3"><a href="#7_3_4_gyroscope">7.3.4. Gyroscope</a></p>
212
213<p class="toc_h3"><a href="#7_3_5_barometer">7.3.5. Barometer</a></p>
214
215<p class="toc_h3"><a href="#7_3_6_thermometer">7.3.6. Thermometer</a></p>
216
217<p class="toc_h3"><a href="#7_3_7_photometer">7.3.7. Photometer</a></p>
218
219<p class="toc_h3"><a href="#7_3_8_proximity_sensor">7.3.8. Proximity Sensor</a></p>
220
221<p class="toc_h2"><a href="#7_4_data_connectivity">7.4. Data Connectivity</a></p>
222
223<p class="toc_h3"><a href="#7_4_1_telephony">7.4.1. Telephony</a></p>
224
225<p class="toc_h3"><a href="#7_4_2_ieee_80211_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
226
227<p class="toc_h4"><a href="#7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</a></p>
228
229<p class="toc_h4"><a href="#7_4_2_2_wi-fi-tunneled-direct-link-setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</a></p>
230
231<p class="toc_h3"><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></p>
232
233<p class="toc_h3"><a href="#7_4_4_near-field_communications">7.4.4. Near-Field Communications</a></p>
234
235<p class="toc_h3"><a href="#7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</a></p>
236
237<p class="toc_h3"><a href="#7_4_6_sync_settings">7.4.6. Sync Settings</a></p>
238
239<p class="toc_h2"><a href="#7_5_cameras">7.5. Cameras</a></p>
240
241<p class="toc_h3"><a href="#7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</a></p>
242
243<p class="toc_h3"><a href="#7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</a></p>
244
245<p class="toc_h3"><a href="#7_5_3_external_camera">7.5.3. External Camera</a></p>
246
247<p class="toc_h3"><a href="#7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</a></p>
248
249
250
251
252
253</div>
254
255<div id="toc_right_2">
256
257<p class="toc_h3"><a href="#7_5_5_camera_orientation">7.5.5. Camera Orientation</a></p>
258
259<p class="toc_h2"><a href="#7_6_memory_and_storage">7.6. Memory and Storage</a></p>
260
261<p class="toc_h3"><a href="#7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</a></p>
262
263<p class="toc_h3"><a href="#7_6_2_application_shared_storage">7.6.2. Application Shared Storage</a></p>
264
265<p class="toc_h2"><a href="#7_7_usb">7.7. USB</a></p>
266
267<p class="toc_h2"><a href="#7_8_audio">7.8. Audio</a></p>
268
269<p class="toc_h3"><a href="#7_8_1_microphone">7.8.1. Microphone</a></p>
270
271<p class="toc_h3"><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></p>
272
273<p class="toc_h4"><a href="#7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</a></p>
274
275<p class="toc_h1"><a href="#8_performance_compatibility">8. Performance Compatibility</a></p>
276
277<p class="toc_h2"><a href="#8_1_user_experience_consistency">8.1. User Experience Consistency</a></p>
278
279<p class="toc_h2"><a href="#8_2_memory_performance">8.2. Memory Performance</a></p>
280
281<p class="toc_h1"><a href="#9_security_model_compatibility">9. Security Model Compatibility</a></p>
282
283<p class="toc_h2"><a href="#9_1_permissions">9.1. Permissions</a></p>
284
285<p class="toc_h2"><a href="#9_2_uid_and_process_isolation">9.2. UID and Process Isolation</a></p>
286
287<p class="toc_h2"><a href="#9_3_filesystem_permissions">9.3. Filesystem Permissions</a></p>
288
289<p class="toc_h2"><a href="#9_4_alternate_execution_environments">9.4. Alternate Execution Environments</a></p>
290
291<p class="toc_h2"><a href="#9_5_multi-user_support">9.5. Multi-User Support</a></p>
292
293<p class="toc_h2"><a href="#9_6_premium_sms_warning">9.6. Premium SMS Warning</a></p>
294
295<p class="toc_h2"><a href="#9_7_kernel_security_features">9.7. Kernel Security Features</a></p>
296
297<p class="toc_h2"><a href="#9_8_privacy">9.8. Privacy</a></p>
298
299<p class="toc_h2"><a href="#9_9_full-disk-encryption">9.9. Full-Disk Encryption</a></p>
300
301<p class="toc_h2"><a href="#9_10_verified_boot">9.10. Verified Boot</a></p>
302
303<p class="toc_h1"><a href="#10_software_compatibility_testing">10. Software Compatibility Testing</a></p>
304
305<p class="toc_h2"><a href="#10_1_compatibility_test_suite">10.1. Compatibility Test Suite</a></p>
306
307<p class="toc_h2"><a href="#10_2_cts_verifier">10.2. CTS Verifier</a></p>
308
309<p class="toc_h1"><a href="#11_updatable_software">11. Updatable Software</a></p>
310
311<p class="toc_h1"><a href="#12_document_changelog">12. Document Changelog</a></p>
312
313<p class="toc_h1"><a href="#13_contact_us">13. Contact Us</a></p>
314
315<p class="toc_h1"><a href="#14_resources">14. Resources</a></p>
316
317</div>
318
319</div>
320
321<div style="clear: both"></div>
322
323<div id="main">
324
325<h1 id="1_introduction">1. Introduction</h1>
326
327
328<p>This document enumerates the requirements that must be met in order for devices
329to be compatible with Android ANDROID_VERSION.</p>
330
331<p>The use of &ldquo;MUST&rdquo;, &ldquo;MUST NOT&rdquo;, &ldquo;REQUIRED&rdquo;, &ldquo;SHALL&rdquo;, &ldquo;SHALL NOT&rdquo;, &ldquo;SHOULD&rdquo;,&ldquo;SHOULD NOT&rdquo;, &ldquo;RECOMMENDED&rdquo;, &ldquo;MAY&rdquo;, and &ldquo;OPTIONAL&rdquo; is per the IETF standard
332defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
333
334<p>As used in this document, a &ldquo;device implementer&rdquo; or &ldquo;implementer&rdquo; is a person
335or organization developing a hardware/software solution running Android ANDROID_VERSION. A
336&ldquo;device implementation&rdquo; or &ldquo;implementation is the hardware/software solution
337so developed.</p>
338
339<p>To be considered compatible with Android ANDROID_VERSION, device implementations MUST meet
340the requirements presented in this Compatibility Definition, including any
341documents incorporated via reference.</p>
342
343<p>Where this definition or the software tests described in <a href="#10_software_compatibility_testing">section 10</a> is silent, ambiguous, or incomplete, it is the responsibility of the device
344implementer to ensure compatibility with existing implementations.</p>
345
346<p>For this reason, the Android Open Source Project [<a href="http://source.android.com/">Resources, 2</a>] is both the reference and preferred implementation of Android. Device
347implementers are strongly encouraged to base their implementations to the
348greatest extent possible on the &ldquo;upstream&rdquo; source code available from the
349Android Open Source Project. While some components can hypothetically be
350replaced with alternate implementations this practice is strongly discouraged,
351as passing the software tests will become substantially more difficult. It is
352the implementer&rsquo;s responsibility to ensure full behavioral compatibility with
353the standard Android implementation, including and beyond the Compatibility
354Test Suite. Finally, note that certain component substitutions and
355modifications are explicitly forbidden by this document.</p>
356
357<p>Many of the resources listed in <a href="#14_resources">section 14</a> are derived directly or indirectly from the Android SDK, and will be
358functionally identical to the information in that SDK&rsquo;s documentation. For any
359case where this Compatibility Definition or the Compatibility Test Suite
360disagrees with the SDK documentation, the SDK documentation is considered
361authoritative. Any technical details provided in the references included in <a href="#14_resources">section 14</a> are considered by inclusion to be part of this Compatibility Definition. </p>
362
363<h1 id="2_device_types">2. Device Types</h1>
364
365
366<p>While the Android Open Source Project has been used in the implementation of a
367variety of device types and form factors, many aspects of the architecture and
368compatibility requirements were optimized for handheld devices. Starting from
369Android 5.0, the Android Open Source Project aims to embrace a wider variety of
370device types as described in this section.</p>
371
372<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
373it in the hand, such as mp3 players, phones, and tablets. Android Handheld
374device implementations:</p>
375
376<ul>
377 <li>MUST have a touchscreen embedded in the device.</li>
378 <li>MUST have a power source that provides mobility, such as a battery.</li>
379</ul>
380
381<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
382for consuming digital media, movies, games, apps, and/or live TV for users
383sitting about ten feet away (a &ldquo;lean back&rdquo; or &ldquo;10-foot user interface&rdquo;).
384Android Television devices:</p>
385
386<ul>
387 <li>MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
388or a wireless port for display.</li>
389 <li>MUST declare the features android.software.leanback and
390android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>].</li>
391</ul>
392
393<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
394perhaps on the wrist, and:</p>
395
396<ul>
397 <li>MUST have a screen with the physical diagonal length in the range from 1.1 to
3982.5 inches.</li>
399 <li>MUST declare the feature android.hardware.type.watch.</li>
400 <li>MUST support uiMode = UI_MODE_TYPE_WATCH [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_WATCH">Resources, 4</a>].</li>
401</ul>
402
403<p><strong>Android Automotive implementation</strong> refers to a vehicle head
404unit running Android as an operating system for part or all of the system and/or
405infotainment functionality. Android Automotive implementations MUST support
406uiMode = UI_MODE_TYPE_CAR [<a href="http://developer.android.com/reference/android/content/res/Configuration.html#UI_MODE_TYPE_CAR">Resources, 111</a>].</p>
407
408<p>All Android device implementations that do not fit into any of the above device
409types still MUST meet all requirements in this document to be Android ANDROID_VERSION
410compatible, unless the requirement is explicitly described to be only
411applicable to a specific Android device type from above.</p>
412
413<h2 id="2_1_device_configurations">2.1 Device Configurations</h2>
414
415
416<p>This is a summary of major differences in hardware configuration by device
417type. (Empty cells denote a &ldquo;MAY&rdquo;). Not all configurations are covered in this
418table; see relevant hardware sections for more detail.</p>
419<table>
420 <tr>
421 <th>Category</th>
422 <th>Feature</th>
423 <th>Section</th>
424 <th>Handheld</th>
425 <th>Television</th>
426 <th>Watch</th>
427 <th>Automotive</th>
428 <th>Other</th>
429 </tr>
430 <tr>
431 <td rowspan="3">Input</td>
432 <td>D-pad</td>
433 <td><a href="#7_2_2_non-touch-navigation">7.2.2. Non-touch Navigation</a></td>
434 <td></td>
435 <td>MUST</td>
436 <td></td>
437 <td></td>
438 <td></td>
439 </tr>
440 <tr>
441 <td>Touchscreen </td>
442 <td><a href="#7_2_4_touchscreen_input">7.2.4. Touchscreen input</a></td>
443 <td>MUST</td>
444 <td></td>
445 <td>MUST</td>
446 <td></td>
447 <td>SHOULD</td>
448 </tr>
449 <tr>
450 <td>Microphone </td>
451 <td><a href="#7_8_1_microphone">7.8.1. Microphone</a></td>
452 <td>MUST</td>
453 <td>SHOULD </td>
454 <td>MUST</td>
455 <td>MUST</td>
456 <td>SHOULD</td>
457 </tr>
458 <tr>
459 <td rowspan="2">Sensors</td>
460 <td>Accelerometer </td>
461 <td><a href="#7_3_1_accelerometer">7.3.1 Accelerometer</a></td>
462 <td>SHOULD</td>
463 <td></td>
464 <td>SHOULD</td>
465 <td></td>
466 <td>SHOULD</td>
467 </tr>
468 <tr>
469 <td>GPS</td>
470 <td><a href="#7_3_3_gps">7.3.3. GPS</a></td>
471 <td>SHOULD</td>
472 <td></td>
473 <td></td>
474 <td>SHOULD</td>
475 <td></td>
476 </tr>
477 <tr>
478 <td rowspan="5">Connectivity</td>
479 <td>Wi-Fi</td>
480 <td><a href="#7_4_2_ieee_802.11">7.4.2. IEEE 802.11</a></td>
481 <td>SHOULD</td>
482 <td> MUST</td>
483 <td></td>
484 <td>SHOULD</td>
485 <td>SHOULD</td>
486 </tr>
487 <tr>
488 <td>Wi-Fi Direct</td>
489 <td><a href="#7_4_2_1_wi-fi-direct">7.4.2.1. Wi-Fi Direct</a></td>
490 <td>SHOULD</td>
491 <td>SHOULD</td>
492 <td></td>
493 <td></td>
494 <td>SHOULD</td>
495 </tr>
496 <tr>
497 <td>Bluetooth</td>
498 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
499 <td>SHOULD</td>
500 <td>MUST</td>
501 <td>MUST</td>
502 <td>MUST</td>
503 <td>SHOULD</td>
504 </tr>
505 <tr>
506 <td>Bluetooth Low Energy</td>
507 <td><a href="#7_4_3_bluetooth">7.4.3. Bluetooth</a></td>
508 <td>SHOULD</td>
509 <td>MUST</td>
510 <td>SHOULD</td>
511 <td>SHOULD</td>
512 <td>SHOULD</td>
513 </tr>
514 <tr>
515 <td>USB peripheral/host mode</td>
516 <td><a href="#7_7_usb">7.7. USB</a></td>
517 <td>SHOULD</td>
518 <td></td>
519 <td></td>
520 <td>SHOULD</td>
521 <td>SHOULD</td>
522 </tr>
523 <tr>
524 <td>Output</td>
525 <td>Speaker and/or Audio output ports</td>
526 <td><a href="#7_8_2_audio_output">7.8.2. Audio Output</a></td>
527 <td>MUST</td>
528 <td>MUST</td>
529 <td></td>
530 <td>MUST</td>
531 <td>MUST</td>
532 </tr>
533</table>
534
535
536<h1 id="3_software">3. Software</h1>
537
538
539<h2 id="3_1_managed_api_compatibility">3.1. Managed API Compatibility</h2>
540
541
542<p>The managed Dalvik bytecode execution environment is the primary vehicle for
543Android applications. The Android application programming interface (API) is
544the set of Android platform interfaces exposed to applications running in the
545managed runtime environment. Device implementations MUST provide complete
546implementations, including all documented behaviors, of any documented API
547exposed by the Android SDK [<a href="http://developer.android.com/reference/packages.html">Resources, 5</a>] or any API decorated with the &ldquo;@SystemApi&rdquo; marker in the upstream Android
548source code. </p>
549
550<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
551signatures, deviate from the documented behavior, or include no-ops, except
552where specifically allowed by this Compatibility Definition.</p>
553
554<p>This Compatibility Definition permits some types of hardware for which Android
555includes APIs to be omitted by device implementations. In such cases, the APIs
556MUST still be present and behave in a reasonable way. See <a href="#7_hardware_compatibility">section 7</a> for specific requirements for this scenario.</p>
557
558<h2 id="3_2_soft_api_compatibility">3.2. Soft API Compatibility</h2>
559
560
561<p>In addition to the managed APIs from <a href="#3_1_managed_api_compatibility">section 3.1</a>, Android also includes a significant runtime-only &ldquo;soft&rdquo; API, in the form of
562such things as intents, permissions, and similar aspects of Android
563applications that cannot be enforced at application compile time.</p>
564
565<h3 id="3_2_1_permissions">3.2.1. Permissions</h3>
566
567
568<p>Device implementers MUST support and enforce all permission constants as
569documented by the Permission reference page [<a href="http://developer.android.com/reference/android/Manifest.permission.html">Resources, 6]</a>. Note that <a href="#9_security_model_compatibility">section 9</a> lists additional requirements related to the Android security model.</p>
570
571<h3 id="3_2_2_build_parameters">3.2.2. Build Parameters</h3>
572
573
574<p>The Android APIs include a number of constants on the android.os.Build class [<a href="http://developer.android.com/reference/android/os/Build.html">Resources, 7</a>] that are intended to describe the current device. To provide consistent,
575meaningful values across device implementations, the table below includes
576additional restrictions on the formats of these values to which device
577implementations MUST conform.</p>
578<table>
579 <tr>
580 <th>Parameter</th>
581 <th>Details</th>
582 </tr>
583 <tr>
584 <td>VERSION.RELEASE</td>
585 <td>The version of the currently-executing Android system, in human-readable
586format. This field MUST have one of the string values defined in [<a href="http://source.android.com/compatibility/ANDROID_VERSION/versions.html">Resources, 8]</a>.</td>
587 </tr>
588 <tr>
589 <td>VERSION.SDK</td>
590 <td>The version of the currently-executing Android system, in a format accessible
591to third-party application code. For Android ANDROID_VERSION, this field MUST have the
592integer value 22.</td>
593 </tr>
594 <tr>
595 <td>VERSION.SDK_INT</td>
596 <td>The version of the currently-executing Android system, in a format accessible
597to third-party application code. For Android ANDROID_VERSION, this field MUST have the
598integer value 22.</td>
599 </tr>
600 <tr>
601 <td>VERSION.INCREMENTAL</td>
602 <td>A value chosen by the device implementer designating the specific build of the
603currently-executing Android system, in human-readable format. This value MUST
604NOT be reused for different builds made available to end users. A typical use
605of this field is to indicate which build number or source-control change
606identifier was used to generate the build. There are no requirements on the
607specific format of this field, except that it MUST NOT be null or the empty
608string ("").</td>
609 </tr>
610 <tr>
611 <td>BOARD</td>
612 <td>A value chosen by the device implementer identifying the specific internal
613hardware used by the device, in human-readable format. A possible use of this
614field is to indicate the specific revision of the board powering the device.
615The value of this field MUST be encodable as 7-bit ASCII and match the regular
616expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
617 </tr>
618 <tr>
619 <td>BRAND</td>
620 <td>A value reflecting the brand name associated with the device as known to the
621end users. MUST be in human-readable format and SHOULD represent the
622manufacturer of the device or the company brand under which the device is
623marketed. The value of this field MUST be encodable as 7-bit ASCII and match
624the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
625 </tr>
626 <tr>
627 <td>SUPPORTED_ABIS</td>
628 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
629 </tr>
630 <tr>
631 <td>SUPPORTED_32_BIT_ABIS</td>
632 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
633 </tr>
634 <tr>
635 <td>SUPPORTED_64_BIT_ABIS</td>
636 <td>The name of the second instruction set (CPU type + ABI convention) of native
637code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
638 </tr>
639 <tr>
640 <td>CPU_ABI</td>
641 <td>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
642 </tr>
643 <tr>
644 <td>CPU_ABI2</td>
645 <td>The name of the second instruction set (CPU type + ABI convention) of native
646code. See <a href="#3_3_native_api_compatibility">section 3.3. Native API Compatibility</a>.</td>
647 </tr>
648 <tr>
649 <td>DEVICE</td>
650 <td>A value chosen by the device implementer containing the development name or
651code name identifying the configuration of the hardware features and industrial
652design of the device. The value of this field MUST be encodable as 7-bit ASCII
653and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
654 </tr>
655 <tr>
656 <td>FINGERPRINT</td>
657 <td>A string that uniquely identifies this build. It SHOULD be reasonably
658human-readable. It MUST follow this template:</p>
659
660<p class="small">$(BRAND)/$(PRODUCT)/$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
661
662<p>For example: acme/myproduct/mydevice:ANDROID_VERSION/LMYXX/3359:userdebug/test-keys</p>
663
664<p>The fingerprint MUST NOT include whitespace characters. If other fields
665included in the template above have whitespace characters, they MUST be
666replaced in the build fingerprint with another character, such as the
667underscore ("_") character. The value of this field MUST be encodable as 7-bit
668ASCII.</td>
669 </tr>
670 <tr>
671 <td>HARDWARE</td>
672 <td>The name of the hardware (from the kernel command line or /proc). It SHOULD be
673reasonably human-readable. The value of this field MUST be encodable as 7-bit
674ASCII and match the regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;. </td>
675 </tr>
676 <tr>
677 <td>HOST</td>
678 <td>A string that uniquely identifies the host the build was built on, in
679human-readable format. There are no requirements on the specific format of this
680field, except that it MUST NOT be null or the empty string ("").</td>
681 </tr>
682 <tr>
683 <td>ID</td>
684 <td>An identifier chosen by the device implementer to refer to a specific release,
685in human-readable format. This field can be the same as
686android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
687meaningful for end users to distinguish between software builds. The value of
688this field MUST be encodable as 7-bit ASCII and match the regular expression &ldquo;^[a-zA-Z0-9._-]+$&rdquo;.</td>
689 </tr>
690 <tr>
691 <td>MANUFACTURER</td>
692 <td>The trade name of the Original Equipment Manufacturer (OEM) of the product.
693There are no requirements on the specific format of this field, except that it
694MUST NOT be null or the empty string ("").</td>
695 </tr>
696 <tr>
697 <td>MODEL</td>
698 <td>A value chosen by the device implementer containing the name of the device as
699known to the end user. This SHOULD be the same name under which the device is
700marketed and sold to end users. There are no requirements on the specific
701format of this field, except that it MUST NOT be null or the empty string ("").</td>
702 </tr>
703 <tr>
704 <td>PRODUCT</td>
705 <td>A value chosen by the device implementer containing the development name or
706code name of the specific product (SKU) that MUST be unique within the same
707brand. MUST be human-readable, but is not necessarily intended for view by end
708users. The value of this field MUST be encodable as 7-bit ASCII and match the
709regular expression &ldquo;^[a-zA-Z0-9_-]+$&rdquo;.</td>
710 </tr>
711 <tr>
712 <td>SERIAL</td>
713 <td>A hardware serial number, which MUST be available. The value of this field MUST
714be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
715 </tr>
716 <tr>
717 <td>TAGS</td>
718 <td>A comma-separated list of tags chosen by the device implementer that further
719distinguishes the build. This field MUST have one of the values corresponding
720to the three typical Android platform signing configurations: release-keys,
721dev-keys, test-keys. </td>
722 </tr>
723 <tr>
724 <td>TIME</td>
725 <td>A value representing the timestamp of when the build occurred.</td>
726 </tr>
727 <tr>
728 <td>TYPE</td>
729 <td>A value chosen by the device implementer specifying the runtime configuration
730of the build. This field MUST have one of the values corresponding to the three
731typical Android runtime configurations: user, userdebug, or eng.</td>
732 </tr>
733 <tr>
734 <td>USER</td>
735 <td>A name or user ID of the user (or automated user) that generated the build.
736There are no requirements on the specific format of this field, except that it
737MUST NOT be null or the empty string ("").</td>
738 </tr>
739</table>
740
741
742<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
743
744
745<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
746described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
747implementer MUST provide an Android Activity or Service that specifies a
748matching intent filter that binds to and implements correct behavior for each
749specified intent pattern.</p>
750
751<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
752
753
754<p>Android intents allow application components to request functionality from
755other Android components. The Android upstream project includes a list of
756applications considered core Android applications, which implements several
757intent patterns to perform common actions. The core Android applications are:</p>
758
759<ul>
760 <li>Desk Clock</li>
761 <li>Browser</li>
762 <li>Calendar</li>
763 <li>Contacts</li>
764 <li>Gallery</li>
765 <li>GlobalSearch</li>
766 <li>Launcher</li>
767 <li>Music</li>
768 <li>Settings</li>
769</ul>
770
771<p>Device implementations SHOULD include the core Android applications as
772appropriate but MUST include a component implementing the same intent patterns
773defined by all the &ldquo;public&rdquo; Activity or Service components of these core
774Android applications. Note that Activity or Service components are considered
775&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
776
777<h4 id="3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</h4>
778
779
780<p>As Android is an extensible platform, device implementations MUST allow each
781intent pattern referenced in <a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a> to be overridden by third-party applications. The upstream Android open source
782implementation allows this by default; device implementers MUST NOT attach
783special privileges to system applications' use of these intent patterns, or
784prevent third-party applications from binding to and assuming control of these
785patterns. This prohibition specifically includes but is not limited to
786disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
787multiple applications that all handle the same intent pattern.</p>
788
789<p>However, device implementations MAY provide default activities for specific URI
790patterns (eg. http://play.google.com) if the default activity provides a more
791specific filter for the data URI. For example, an intent filter specifying the
792data URI &ldquo;http://www.android.com&rdquo; is more specific than the browser filter for&ldquo;http://&rdquo;. Device implementations MUST provide a user interface for users to
793modify the default activity for intents.</p>
794
795<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
796
797
798<p>Device implementations MUST NOT include any Android component that honors any
799new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
800string in the android.* or com.android.* namespace. Device implementers MUST
801NOT include any Android components that honor any new intent or broadcast
802intent patterns using an ACTION, CATEGORY, or other key string in a package
803space belonging to another organization. Device implementers MUST NOT alter or
804extend any of the intent patterns used by the core apps listed in <a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. Device implementations MAY include intent patterns using namespaces clearly
805and obviously associated with their own organization. This prohibition is
806analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
807
808<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
809
810
811<p>Third-party applications rely on the platform to broadcast certain intents to
812notify them of changes in the hardware or software environment.
813Android-compatible devices MUST broadcast the public broadcast intents in
814response to appropriate system events. Broadcast intents are described in the
815SDK documentation.</p>
816
817<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
818
819
820<p>Android includes settings that provide users an easy way to select their
821default applications, for example for Home screen or SMS. Where it makes sense,
822device implementations MUST provide a similar settings menu and be compatible
823with the intent filter pattern and API methods described in the SDK
824documentation as below.</p>
825
826<p>Device implementations:</p>
827
828<ul>
829 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
830settings menu for Home Screen, if the device implementation reports
831android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
832 <li>MUST provide a settings menu that will call the
833android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
834change the default SMS application, if the device implementation reports
835android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]</li>
836 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
837app settings menu for Tap and Pay, if the device implementation reports
838android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
839</ul>
840
841<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
842
843
844<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
845
846
847<p>Managed Dalvik bytecode can call into native code provided in the application
848.apk file as an ELF .so file compiled for the appropriate device hardware
849architecture. As native code is highly dependent on the underlying processor
850technology, Android defines a number of Application Binary Interfaces (ABIs) in
851the Android NDK. Device implementations MUST be compatible with one or more
852defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
853
854<p>If a device implementation includes support for an Android ABI, it:</p>
855
856<ul>
857 <li>MUST include support for code running in the managed environment to call into
858native code, using the standard Java Native Interface (JNI) semantics</li>
859 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
860the ABI) with each required library in the list below</li>
861 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
862 <li>MUST accurately report the native Application Binary Interface (ABI) supported
863by the device, via the android.os.Build.SUPPORTED_ABIS,
864android.os.Build.SUPPORTED_32_BIT_ABIS, and
865android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
866of ABIs ordered from the most to the least preferred one</li>
Unsuk Jung06706432015-08-31 11:26:13 -0700[diff] [blame]867 <li>MUST report, via the above parameters, only those ABIs documented and
868described in the latest version of the Android NDK ABI Management documentation
869[<a href="https://developer.android.com/ndk/guides/abis.html">Resources, XX</a>],
870and MUST include support for the Advanced SIMD (a.k.a. NEON)
871[<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">Resources,XX</a>]
872extension
873 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]874 <li>SHOULD be built using the source code and header files available in the
875upstream Android Open Source Project</li>
876</ul>
877
878<p>The following native code APIs MUST be available to apps that include native
879code:</p>
880
881<ul>
882 <li>libc (C library)</li>
883 <li>libm (math library)</li>
884 <li>Minimal support for C++</li>
885 <li>JNI interface</li>
886 <li>liblog (Android logging)</li>
887 <li>libz (Zlib compression)</li>
888 <li>libdl (dynamic linker)</li>
889 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
890 <li>libGLESv2.so (OpenGL ES 2.0)</li>
891 <li>libGLESv3.so (OpenGL ES 3.x)</li>
892 <li>libEGL.so (native OpenGL surface management)</li>
893 <li>libjnigraphics.so</li>
894 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
895 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
896 <li>libandroid.so (native Android activity support)</li>
897 <li>libmediandk.so (native media APIs support)</li>
898 <li>Support for OpenGL, as described below</li>
899</ul>
900
901<p>Note that future releases of the Android NDK may introduce support for
902additional ABIs. If a device implementation is not compatible with an existing
903predefined ABI, it MUST NOT report support for any ABIs at all.</p>
904
905<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
906(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
907Android 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
908symbols must be present, only the corresponding functions for OpenGL ES
909versions and extensions actually supported by the device must be fully
910implemented.</p>
911
912<p>Native code compatibility is challenging. For this reason, device implementers
913are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
914Android Open Source Project. </p>
915
916<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9173.3.2. 32-bit ARM Native Code Compatibility
918</h3>
919
920<p>The ARMv8 architecture deprecates several CPU operations, including some
921operations used in existing native code. On 64-bit ARM devices, the following
922deprecated operations MUST remain available to 32-bit native ARM code, either
923through native CPU support or through software emulation:</p>
924
925<ul>
926<li>SWP and SWPB instructions</li>
927<li>SETEND instruction</li>
928<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
929</ul>
930
931<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
932from 32-bit ARM native code. For compatibility with applications built using this
933NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
934by 32-bit ARM applications:</p>
935
936<ul>
937<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
938supported by the device</li>
939<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
940highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
941</ul>
942
943<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
944applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
945non-ARM applications.</p>
946
947<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
948
949
950<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
951
952<div class="note">
953<p>Android Watch devices MAY, but all other device implementations MUST provide
954a complete implementation of the android.webkit.Webview API.</p>
955</div>
956
957
958<p>The platform feature android.software.webview MUST be reported on any device
959that provides a complete implementation of the android.webkit.WebView API, and
960MUST NOT be reported on devices without a complete implementation of the API.
961The Android Open Source implementation uses code from the Chromium Project to
962implement 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
963rendering system, device implementers MUST use the specific upstream build of
964Chromium in the WebView implementation. Specifically:</p>
965
966<ul>
967 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
968build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
969includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
970 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]971<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]972AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
973Safari/537.36</p>
974 <ul>
975 <li>The value of the $(VERSION) string MUST be the same as the value for
976android.os.Build.VERSION.RELEASE.</li>
977 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
978 note that this is a webview</li>
979 <li>The value of the $(MODEL) string MUST be the same as the value for
980android.os.Build.MODEL.</li>
981 <li>The value of the $(BUILD) string MUST be the same as the value for
982android.os.Build.ID.</li>
983 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
984upstream Android Open Source Project.</li>
985 <li>Device implementations MAY omit Mobile in the user agent string.</li>
986 </ul></li></ul>
987
988<p>The WebView component SHOULD include support for as many HTML5 features as
989possible and if it supports the feature SHOULD conform to the HTML5
990specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
991
992<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
993
994<div class="note">
995<p>Android Television, Watch, and Android Automotive implementations MAY omit a
996browser application, but MUST support the public intent patterns as described in
997<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
998of device implementations MUST include a standalone Browser application for
999general user web browsing.</p>
1000</div>
1001
1002<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1003However, even if an alternate Browser application is used, the
1004android.webkit.WebView component provided to third-party applications MUST be
1005based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1006
1007<p>Implementations MAY ship a custom user agent string in the standalone Browser
1008application.</p>
1009
1010<p>The standalone Browser application (whether based on the upstream WebKit
1011Browser application or a third-party replacement) SHOULD include support for as
1012much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1013APIs associated with HTML5:</p>
1014
1015<ul>
1016 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1017 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1018 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1019</ul>
1020
1021<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1022[<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
1023IndexedDB over webstorage, IndexedDB is expected to become a required component
1024in a future version of Android.</p>
1025
1026<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1027
1028
1029<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1030consistent with the preferred implementation of the upstream Android Open
1031Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1032
1033<ul>
1034 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1035 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1036type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1037 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1038</ul>
1039
1040<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1041significant portions of the platform for behavioral compatibility, but not all.
1042It is the responsibility of the implementer to ensure behavioral compatibility
1043with the Android Open Source Project. For this reason, device implementers
1044SHOULD use the source code available via the Android Open Source Project where
1045possible, rather than re-implement significant parts of the system.</p>
1046
1047<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1048
1049
1050<p>Android follows the package and class namespace conventions defined by the Java
1051programming language. To ensure compatibility with third-party applications,
1052device implementers MUST NOT make any prohibited modifications (see below) to
1053these package namespaces:</p>
1054
1055<ul>
1056 <li>java.*</li>
1057 <li>javax.*</li>
1058 <li>sun.*</li>
1059 <li>android.*</li>
1060 <li>com.android.*</li>
1061</ul>
1062
1063<p><strong>Prohibited modifications include</strong>:</p>
1064
1065<ul>
1066 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1067platform by changing any method or class signatures, or by removing classes or
1068class fields.</li>
1069 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1070such modifications MUST NOT impact the stated behavior and Java-language
1071signature of any publicly exposed APIs.</li>
1072 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1073or interfaces, or fields or methods to existing classes or interfaces) to the
1074APIs above.</li>
1075</ul>
1076
1077<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,
1078device implementers MUST NOT expose new APIs or alter existing APIs in the
1079namespaces noted above. Device implementers MAY make internal-only
1080modifications, but those modifications MUST NOT be advertised or otherwise
1081exposed to developers.</p>
1082
1083<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1084namespace owned by or referring to another organization. For instance, device
1085implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1086Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1087namespaces. Additionally, if a device implementation includes custom APIs
1088outside the standard Android namespace, those APIs MUST be packaged in an
1089Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1090lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1091APIs.</p>
1092
1093<p>If a device implementer proposes to improve one of the package namespaces above
1094(such as by adding useful new functionality to an existing API, or adding a new
1095API), 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
1096information on that site.</p>
1097
1098<p>Note that the restrictions above correspond to standard conventions for naming
1099APIs in the Java programming language; this section simply aims to reinforce
1100those conventions and make them binding through inclusion in this Compatibility
1101Definition.</p>
1102
1103<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1104
1105
1106<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1107Dalvik 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
1108the Dalvik Executable Format, and the reference implementation&rsquo;s package
1109management system.</p>
1110
1111<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1112accordance with the upstream Android platform, and as specified by the
1113following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1114
1115<p>Note that memory values specified below are considered minimum values and
1116device implementations MAY allocate more memory per application.</p>
1117
1118<table>
1119 <tr>
1120 <th>Screen Layout</th>
1121 <th>Screen Density</th>
1122 <th>Minimum Application Memory</th>
1123 </tr>
1124 <tr>
1125 <td rowspan="10">small/normal</td>
1126 <td>120 dpi (ldpi)</td>
1127 <td rowspan="2">32MB</td>
1128 </tr>
1129 <tr>
1130 <td>160 dpi (mdpi)</td>
1131 </tr>
1132 <tr>
1133 <td>213 dpi (tvdpi)</td>
1134 <td rowspan="3">48MB</td>
1135 </tr>
1136 <tr>
1137 <td>240 dpi (hdpi)</td>
1138 </tr>
1139 <tr>
1140 <td>280 dpi (280dpi)</td>
1141 </tr>
1142 <tr>
1143 <td>320 dpi (xhdpi)</td>
1144 <td>80MB</td>
1145 </tr>
1146 <tr>
1147 <td>400 dpi (400dpi)</td>
1148 <td>96MB</td>
1149 </tr>
1150 <tr>
1151 <td>480 dpi (xxhdpi)</td>
1152 <td>128MB</td>
1153 </tr>
1154 <tr>
1155 <td>560 dpi (560dpi)</td>
1156 <td>192MB</td>
1157 </tr>
1158 <tr>
1159 <td>640 dpi (xxxhdpi)</td>
1160 <td>256MB</td>
1161 </tr>
1162 <tr>
1163 <td rowspan="10">large</td>
1164 <td>120 dpi (ldpi)</td>
1165 <td>32MB</td>
1166 </tr>
1167 <tr>
1168 <td>160 dpi (mdpi)</td>
1169 <td>48MB</td>
1170 </tr>
1171 <tr>
1172 <td>213 dpi (tvdpi)</td>
1173 <td rowspan="2">80MB</td>
1174 </tr>
1175 <tr>
1176 <td>240 dpi (hdpi)</td>
1177 </tr>
1178 <tr>
1179 <td>280 dpi (280dpi)</td>
1180 <td>96MB</td>
1181 </tr>
1182 <tr>
1183 <td>320 dpi (xhdpi)</td>
1184 <td>128MB</td>
1185 </tr>
1186 <tr>
1187 <td>400 dpi (400dpi)</td>
1188 <td>192MB</td>
1189 </tr>
1190 <tr>
1191 <td>480 dpi (xxhdpi)</td>
1192 <td>256MB</td>
1193 </tr>
1194 <tr>
1195 <td>560 dpi (560dpi)</td>
1196 <td>384MB</td>
1197 </tr>
1198 <tr>
1199 <td>640 dpi (xxxhdpi)</td>
1200 <td>512MB</td>
1201 </tr>
1202 <tr>
1203 <td rowspan="10">xlarge</td>
1204 <td>120 dpi (ldpi)</td>
1205 <td>48MB</td>
1206 </tr>
1207 <tr>
1208 <td>160 dpi (mdpi)</td>
1209 <td>80MB</td>
1210 </tr>
1211 <tr>
1212 <td>213 dpi (tvdpi)</td>
1213 <td rowspan="2">96MB</td>
1214 </tr>
1215 <tr>
1216 <td>240 dpi (hdpi)</td>
1217 </tr>
1218 <tr>
1219 <td>280 dpi (280dpi)</td>
1220 <td>144MB</td>
1221 </tr>
1222 <tr>
1223 <td>320 dpi (xhdpi)</td>
1224 <td>192MB</td>
1225 </tr>
1226 <tr>
1227 <td>400 dpi (400dpi)</td>
1228 <td>288MB</td>
1229 </tr>
1230 <tr>
1231 <td>480 dpi (xxhdpi)</td>
1232 <td>384MB</td>
1233 </tr>
1234 <tr>
1235 <td>560 dpi (560dpi)</td>
1236 <td>576MB</td>
1237 </tr>
1238 <tr>
1239 <td>640 dpi (xxxhdpi)</td>
1240 <td>768MB</td>
1241 </tr>
1242</table>
1243
1244
1245<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1246
1247
1248<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1249
1250
1251<p>Android includes a launcher application (home screen) and support for
1252third-party applications to replace the device launcher (home screen). Device
1253implementations that allow third-party applications to replace the device home
1254screen MUST declare the platform feature android.software.home_screen.</p>
1255
1256<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1257
1258<div class="note">
1259<p>Widgets are optional for all Android device implementations, but SHOULD be
1260supported on Android Handheld devices.</p>
1261</div>
1262
1263
1264<p>Android defines a component type and corresponding API and lifecycle that
1265allows 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
1266implementations. Device implementations that support embedding widgets on the
1267home screen MUST meet the following requirements and declare support for
1268platform feature android.software.app_widgets.</p>
1269
1270<ul>
1271 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1272interface affordances to add, configure, view, and remove AppWidgets directly
1273within the Launcher.</li>
1274 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1275the standard grid size. See the App Widget Design Guidelines in the Android SDK
1276documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1277 <li>Device implementations that include support for lock screen MAY support
1278application widgets on the lock screen.</li>
1279</ul>
1280
1281<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1282
1283
1284<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>
1285
1286<p>Some APIs allow applications to perform notifications or attract attention
1287using hardware&#8212;specifically sound, vibration, and light. Device implementations
1288MUST support notifications that use hardware features, as described in the SDK
1289documentation, and to the extent possible with the device implementation
1290hardware. For instance, if a device implementation includes a vibrator, it MUST
1291correctly implement the vibration APIs. If a device implementation lacks
1292hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1293is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1294
1295<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1296etc.) provided for in the APIs
1297[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1298or in the Status/System Bar icon style guide
1299[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1300which in the case of an Android Television device includes the possibility to not display the
1301notifications. Device implementers MAY provide an alternative user experience for
1302notifications than that provided by the reference Android Open Source
1303implementation; however, such alternative notification systems MUST support
1304existing notification resources, as above. </p>
1305
1306<p>Android includes support for various notifications, such as:</p>
1307
1308<ul>
1309 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1310 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1311 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1312</ul>
1313
1314<p>Android device implementations, when such notifications are made visible, MUST properly execute
1315Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1316APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1317</p>
1318
1319<p>Android includes Notification Listener Service APIs that allow apps (once
1320explicitly enabled by the user) to receive a copy of all notifications as they
1321are posted or updated. Device implementations MUST correctly and promptly send
1322notifications in their entirety to all such installed and user-enabled listener
1323services, including any and all metadata attached to the Notification object.</p>
1324
1325<h3 id="3_8_4_search">3.8.4. Search</h3>
1326
1327
1328<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
1329expose their application&rsquo;s data into the global system search. Generally
1330speaking, this functionality consists of a single, system-wide user interface
1331that allows users to enter queries, displays suggestions as users type, and
1332displays results. The Android APIs allow developers to reuse this interface to
1333provide search within their own apps, and allow developers to supply results to
1334the common global search user interface.</p>
1335
1336<p>Android device implementations SHOULD include global search, a single, shared,
1337system-wide search user interface capable of real-time suggestions in response
1338to user input. Device implementations SHOULD implement the APIs that allow
1339developers to reuse this user interface to provide search within their own
1340applications. Device implementations that implement the global search interface
1341MUST implement the APIs that allow third-party applications to add suggestions
1342to the search box when it is run in global search mode. If no third-party
1343applications are installed that make use of this functionality, the default
1344behavior SHOULD be to display web search engine results and suggestions.</p>
1345
1346<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1347
1348
1349<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1350end 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
1351some high-visibility manner.</p>
1352
1353<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1354
1355
1356<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1357across an entire Activity or application.</p>
1358
1359<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1360application developers to use if they want to match the Holo theme look and
1361feel 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
1362exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1363
1364<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1365application developers to use if they want to match the design theme&rsquo;s look and
1366feel across the wide variety of different Android device types. Device
1367implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1368of 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>
1369
1370<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1371styles for application developers to use if they want to match the look and
1372feel of the device theme as defined by the device implementer. Device
1373implementations MAY modify the Device Default theme attributes exposed to
1374applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1375
1376<p>Android supports a new variant theme with translucent system bars, which allows
1377application developers to fill the area behind the status and navigation bar
1378with their app content. To enable a consistent developer experience in this
1379configuration, it is important the status bar icon style is maintained across
1380different device implementations. Therefore, Android device implementations
1381MUST use white for system status icons (such as signal strength and battery
1382level) and notifications issued by the system, unless the icon is indicating a
1383problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1384
1385<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1386
1387
1388<p>Android defines a component type and corresponding API and lifecycle that
1389allows 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
1390input capabilities that display as a wallpaper, behind other applications.</p>
1391
1392<p>Hardware is considered capable of reliably running live wallpapers if it can
1393run all live wallpapers, with no limitations on functionality, at a reasonable
1394frame rate with no adverse effects on other applications. If limitations in the
1395hardware cause wallpapers and/or applications to crash, malfunction, consume
1396excessive CPU or battery power, or run at unacceptably low frame rates, the
1397hardware is considered incapable of running live wallpaper. As an example, some
1398live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1399Live wallpaper will not run reliably on hardware that does not support multiple
1400OpenGL contexts because the live wallpaper use of an OpenGL context may
1401conflict with other applications that also use an OpenGL context.</p>
1402
1403<p>Device implementations capable of running live wallpapers reliably as described
1404above SHOULD implement live wallpapers, and when implemented MUST report the
1405platform feature flag android.software.live_wallpaper.</p>
1406
1407<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1408
1409<div class="note">
1410<p>As the Recent function navigation key is OPTIONAL, the requirements to
1411implement the overview screen is OPTIONAL for Android Television devices and
1412Android Watch devices.</p>
1413</div>
1414
1415
1416<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
1417accessed activities and tasks using a thumbnail image of the application&rsquo;s
1418graphical state at the moment the user last left the application. Device
1419implementations 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>
1420
1421<ul>
1422 <li>MUST display affiliated recents as a group that moves together.</li>
1423 <li>MUST support at least up to 20 displayed activities.</li>
1424 <li>MUST at least display the title of 4 activities at a time.</li>
1425 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1426 <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>
1427 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1428interacts with screens.</li>
1429</ul>
1430
1431<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1432interface (or a similar thumbnail-based interface) for the overview screen.</p>
1433
1434<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1435
1436
1437<p>Android includes support for Input Management and support for third-party input
1438method 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
1439the device MUST declare the platform feature android.software.input_methods and
1440support IME APIs as defined in the Android SDK documentation.</p>
1441
1442<p>Device implementations that declare the android.software.input_methods feature
1443MUST provide a user-accessible mechanism to add and configure third-party input
1444methods. Device implementations MUST display the settings interface in response
1445to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1446
1447<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1448
1449
1450<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1451Media Notification Template that allows media applications to integrate with
1452playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1453Device implementations that support a lock screen, unless an Android Automotive or Watch
1454implementation, MUST display the Lockscreen Notifications including the Media Notification
1455Template.</p>
1456
1457<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1458
1459
1460<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
1461a power source is idle or docked in a desk dock. Android Watch devices MAY
1462implement Dreams, but other types of device implementations SHOULD include
1463support for Dreams and provide a settings option for users to configure Dreams
1464in response to the android.settings.DREAM_SETTINGS intent.</p>
1465
1466<h3 id="3_8_12_location">3.8.12. Location</h3>
1467
1468
1469<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1470location coordinates, location modes MUST be displayed in the Location menu
1471within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1472
1473<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1474
1475
1476<p>Android includes support for color emoji characters. When Android device
1477implementations include an IME, devices SHOULD provide an input method to the
1478user 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>
1479
1480<p>Android includes support for Roboto 2 font with different
1481weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1482sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1483the languages available on the device and full Unicode 7.0 coverage of Latin,
1484Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1485all glyphs in the currency symbols block of Unicode 7.0.</p>
1486
1487<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1488
1489
1490<p>Android includes features that allow security-aware applications to perform
1491device administration functions at the system level, such as enforcing password
1492policies or performing remote wipe, through the Android Device Administration
1493API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1494Device implementations MUST provide an implementation of the DevicePolicyManager class
1495[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1496Device implementations that include support for PIN (numeric) or PASSWORD
1497(alphanumeric) based lock screens MUST support the full range of device
1498administration policies defined in the Android SDK documentation
1499[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1500and report the platform feature android.software.device_admin.</p>
1501
1502<p>Device implementations MAY have a preinstalled application performing device
1503administration functions but this application MUST NOT be set out-of-the box as
1504the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1505
1506<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1507
1508
1509<p>Android provides an accessibility layer that helps users with disabilities to
1510navigate their devices more easily. In addition, Android provides platform APIs
1511that enable accessibility service implementations to receive callbacks for user
1512and system events and generate alternate feedback mechanisms, such as
1513text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1514
1515<p>Device implementations include the following requirements:</p>
1516
1517<ul>
1518<li>Android Automotive implementations SHOULD provide an implementation of the
1519Android accessibility framework consistent with the default Android
1520implementation.</li>
1521<li>Device implementations (Android Automotive excluded) MUST provide an
1522implementation of the Android accessibility framework consistent with the
1523default Android implementation.</li>
1524<li>Device implementations (Android Automotive excluded) MUST support
1525third-party accessibility service implementations through the
1526android.accessibilityservice APIs
1527[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1528<li>Device implementations (Android Automotive excluded) MUST generate
1529AccessibilityEvents and deliver these events to all registered
1530AccessibilityService implementations in a manner consistent with the default
1531Android implementation</li>
1532<li> Device implementations (Android Automotive and Android Watch devices with
1533no audio output excluded), MUST provide a user-accessible mechanism to enable
1534and disable accessibility services, and MUST display this interface in response
1535to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1536</ul>
1537
1538<p>Additionally, device implementations SHOULD provide an implementation of an
1539accessibility service on the device, and SHOULD provide a mechanism for users
1540to enable the accessibility service during device setup. An open source
1541implementation of an accessibility service is available from the Eyes Free
1542project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1543
1544<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1545
1546
1547<p>Android includes APIs that allow applications to make use of text-to-speech
1548(TTS) services and allows service providers to provide implementations of TTS
1549services [<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
1550MUST meet these requirements related to the Android TTS framework. </p>
1551
1552<p>Android Automotive implementations:</p>
1553<ul>
1554<li>MUST support the Android TTS framework APIs.</li>
1555<li>MAY support installation of third-party TTS engines. If supported, partners
1556MUST provide a user-accessible interface that allows the user to select a TTS
1557engine for use at system level.</li>
1558</ul>
1559
1560<p>All other device implementations:</p>
1561
1562<ul>
1563 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1564supporting the languages available on the device. Note that the upstream
1565Android open source software includes a full-featured TTS engine
1566implementation.
1567 <li> MUST support installation of third-party TTS engines
1568 <li> MUST provide a user-accessible interface that allows users to select a TTS
1569engine for use at the system level
1570</ul>
1571
1572<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1573
1574
1575<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1576content to Android Television devices. TIF provides a standard API to create
1577input modules that control Android Television devices. Android Television
1578device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1579
1580<p>Device implementations that support TIF MUST declare the platform feature
1581android.software.live_tv.</p>
1582
1583<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1584
1585
1586<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1587by 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>
1588
1589<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
1590files from installing and running correctly on other compatible devices.</p>
1591
1592<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1593
1594
1595<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1596
1597
1598<p>Device implementations MUST support the core media formats specified in the
1599Android 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
1600implementations MUST support the media formats, encoders, decoders, file types,
1601and container formats defined in the tables below and reported via MediaCodecList
1602[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1603Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1604[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1605113</a>].
1606
1607All of these codecs are
1608provided as software implementations in the preferred Android implementation
1609from the Android Open Source Project.</p>
1610
1611<p>Please note that neither Google nor the Open Handset Alliance make any
1612representation that these codecs are free from third-party patents. Those
1613intending to use this source code in hardware or software products are advised
1614that implementations of this code, including in open source software or
1615shareware, may require patent licenses from the relevant patent holders.</p>
1616
1617<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1618
1619<table>
1620 <tr>
1621 <th>Format/Codec</th>
1622 <th>Encoder</th>
1623 <th>Decoder</th>
1624 <th>Details</th>
1625 <th>Supported File Types/Container Formats</th>
1626 </tr>
1627 <tr>
1628 <td>MPEG-4 AAC Profile</p>
1629
1630<p>(AAC LC)</td>
1631 <td>REQUIRED<sup>1</sup></td>
1632 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1633 <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]163448 kHz.</td>
1635 <td>
1636 <ul>
1637 <li class="table_list">3GPP (.3gp)</li>
1638 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1639 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1640supported)</li>
1641 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1642 </tr>
1643 <tr>
1644 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1645 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1646 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1647 <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]1648to 48 kHz.</td>
1649 <td></td>
1650 </tr>
1651 <tr>
1652 <td>MPEG-4 HE AACv2</p>
1653
1654<p>Profile (enhanced AAC+)</td>
1655 <td> </td>
1656 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1657 <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]1658to 48 kHz.</td>
1659 <td></td>
1660 </tr>
1661 <tr>
1662 <td>AAC ELD (enhanced low delay AAC)</td>
1663 <td>REQUIRED<sup>1</sup> </p>
1664
1665<p>(Android 4.1+)</td>
1666 <td>REQUIRED</p>
1667
1668<p>(Android 4.1+)</td>
1669 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1670 <td></td>
1671 </tr>
1672 <tr>
1673 <td>AMR-NB</td>
1674 <td>REQUIRED<sup>3</sup></td>
1675 <td>REQUIRED<sup>3</sup></td>
1676 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1677 <td>3GPP (.3gp)</td>
1678 </tr>
1679 <tr>
1680 <td>AMR-WB</td>
1681 <td>REQUIRED<sup>3</sup></td>
1682 <td>REQUIRED<sup>3</sup></td>
1683 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1684 <td></td>
1685 </tr>
1686 <tr>
1687 <td>FLAC</td>
1688 <td></td>
1689 <td>REQUIRED <br>(Android 3.1+)</td>
1690 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1691recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1692does not include a low-pass filter). 16-bit recommended; no dither applied for
169324-bit.</td>
1694 <td>FLAC (.flac) only</td>
1695 </tr>
1696 <tr>
1697 <td>MP3</td>
1698 <td></td>
1699 <td>REQUIRED</td>
1700 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1701 <td>MP3 (.mp3)</td>
1702 </tr>
1703 <tr>
1704 <td>MIDI</td>
1705 <td></td>
1706 <td>REQUIRED</td>
1707 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1708ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1709 <td><ul>
1710 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1711 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1712 <li class="table_list">OTA (.ota)</li>
1713 <li class="table_list">iMelody (.imy)</li></ul></td>
1714 </tr>
1715 <tr>
1716 <td>Vorbis</td>
1717 <td></td>
1718 <td>REQUIRED</td>
1719 <td></td>
1720 <td><ul>
1721 <li class="table_list">Ogg (.ogg)</li>
1722 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1723 </tr>
1724 <tr>
1725 <td>PCM/WAVE</td>
1726 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1727 <td>REQUIRED</td>
1728 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1729sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1730frequencies.</td>
1731 <td>WAVE (.wav)</td>
1732 </tr>
1733 <tr>
1734 <td>Opus</td>
1735 <td></td>
1736 <td>REQUIRED<br> (Android 5.0+)</td>
1737 <td></td>
1738 <td>Matroska (.mkv)</td>
1739 </tr>
1740</table>
1741
1742
1743<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1744but optional for Android Watch device implementations.</p>
1745
1746<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17472 channels is optional.</p>
1748
1749<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1750
1751<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1752including Android Watch device implementations.</p>
1753
1754<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1755
1756<table>
1757 <tr>
1758 <th>Format/Codec</th>
1759 <th>Encoder</th>
1760 <th>Decoder</th>
1761 <th>Details</th>
1762 <th>Supported File Types/Container Formats</th>
1763 </tr>
1764 <tr>
1765 <td>JPEG</td>
1766 <td>REQUIRED</td>
1767 <td>REQUIRED</td>
1768 <td>Base+progressive</td>
1769 <td>JPEG (.jpg)</td>
1770 </tr>
1771 <tr>
1772 <td>GIF</td>
1773 <td></td>
1774 <td>REQUIRED</td>
1775 <td></td>
1776 <td>GIF (.gif)</td>
1777 </tr>
1778 <tr>
1779 <td>PNG</td>
1780 <td>REQUIRED</td>
1781 <td>REQUIRED</td>
1782 <td></td>
1783 <td>PNG (.png)</td>
1784 </tr>
1785 <tr>
1786 <td>BMP</td>
1787 <td></td>
1788 <td>REQUIRED</td>
1789 <td></td>
1790 <td>BMP (.bmp)</td>
1791 </tr>
1792 <tr>
1793 <td>WebP</td>
1794 <td>REQUIRED</td>
1795 <td>REQUIRED</td>
1796 <td></td>
1797 <td>WebP (.webp)</td>
1798 </tr>
1799</table>
1800
1801
1802<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1803
1804<p>Video codecs are optional for Android Watch device implementations.</p>
1805
1806<table>
1807 <tr>
1808 <th>Format/Codec</th>
1809 <th>Encoder</th>
1810 <th>Decoder</th>
1811 <th>Details</th>
1812 <th>Supported File Types/<br>Container Formats</th>
1813 </tr>
1814 <tr>
1815 <td>H.263</td>
1816 <td>REQUIRED<sup>1</sup></td>
1817 <td>REQUIRED<sup>2</sup></td>
1818 <td></td>
1819 <td><ul>
1820 <li class="table_list">3GPP (.3gp)</li>
1821 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1822 </tr>
1823 <tr>
1824 <td>H.264 AVC</td>
1825 <td>REQUIRED<sup>2</sup></td>
1826 <td>REQUIRED<sup>2</sup></td>
1827 <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>
1828 <td><ul>
1829 <li class="table_list">3GPP (.3gp)</li>
1830 <li class="table_list">MPEG-4 (.mp4)</li>
1831 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1832 </tr>
1833 <tr>
1834 <td>H.265 HEVC</td>
1835 <td></td>
1836 <td>REQUIRED<sup>5</sup></td>
1837 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1838 <td>MPEG-4 (.mp4)</td>
1839 </tr>
1840 <tr>
1841 <td>MPEG-4 SP</td>
1842 <td></td>
1843 <td>REQUIRED<sup>2</sup></td>
1844 <td></td>
1845 <td>3GPP (.3gp)</td>
1846 </tr>
1847 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1848 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1849 <td>REQUIRED<sup>2</sup></p>
1850
1851<p>(Android 4.3+)</td>
1852 <td>REQUIRED<sup>2</sup></p>
1853
1854<p>(Android 2.3.3+)</td>
1855 <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>
1856 <td><ul>
1857 <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]1858 <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]1859 </tr>
1860 <tr>
1861 <td>VP9</td>
1862 <td></td>
1863 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1864 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1865 <td><ul>
1866 <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]1867 <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]1868 </tr>
1869</table>
1870
1871
1872<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1873android.hardware.camera or android.hardware.camera.front.</p>
1874
1875<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1876
1877<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1878device implementations SHOULD use a hardware VP8 codec that meets the
1879requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1880
1881<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1882
1883<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1884
1885<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1886
1887<div class="note">
1888<p>Video codecs are optional for Android Watch device implementations.</p>
1889</div>
1890
1891
1892<p>Android device implementations with H.264 codec support, MUST support Baseline
1893Profile Level 3 and the following SD (Standard Definition) video encoding
1894profiles and SHOULD support Main Profile Level 4 and the following HD (High
1895Definition) video encoding profiles. Android Television devices are STRONGLY
1896RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1897<table>
1898 <tr>
1899 <th></th>
1900 <th>SD (Low quality)</th>
1901 <th>SD (High quality)</th>
1902 <th>HD 720p1</th>
1903 <th>HD 1080p1</th>
1904 </tr>
1905 <tr>
1906 <th>Video resolution</th>
1907 <td>320 x 240 px</td>
1908 <td>720 x 480 px</td>
1909 <td>1280 x 720 px</td>
1910 <td>1920 x 1080 px</td>
1911 </tr>
1912 <tr>
1913 <th>Video frame rate</th>
1914 <td>20 fps</td>
1915 <td>30 fps</td>
1916 <td>30 fps</td>
1917 <td>30 fps</td>
1918 </tr>
1919 <tr>
1920 <th>Video bitrate</th>
1921 <td>384 Kbps</td>
1922 <td>2 Mbps</td>
1923 <td>4 Mbps</td>
1924 <td>10 Mbps</td>
1925 </tr>
1926</table>
1927
1928
1929<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1930devices.</p>
1931
1932<p>Android device implementations with VP8 codec support MUST support the SD video
1933encoding profiles and SHOULD support the following HD (High Definition) video
1934encoding profiles.</p>
1935<table>
1936 <tr>
1937 <th></th>
1938 <th>SD (Low quality)</th>
1939 <th>SD (High quality)</th>
1940 <th>HD 720p1</th>
1941 <th>HD 1080p1</th>
1942 </tr>
1943 <tr>
1944 <th>Video resolution</th>
1945 <td>320 x 180 px</td>
1946 <td>640 x 360 px</td>
1947 <td>1280 x 720 px</td>
1948 <td>1920 x 1080 px</td>
1949 </tr>
1950 <tr>
1951 <th>Video frame rate</th>
1952 <td>30 fps</td>
1953 <td>30 fps</td>
1954 <td>30 fps</td>
1955 <td>30 fps</td>
1956 </tr>
1957 <tr>
1958 <th>Video bitrate</th>
1959 <td>800 Kbps </td>
1960 <td>2 Mbps</td>
1961 <td>4 Mbps</td>
1962 <td>10 Mbps</td>
1963 </tr>
1964</table>
1965
1966<p class="table_footnote">1 When supported by hardware.</p>
1967
1968<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1969
1970<div class="note">
1971<p>Video codecs are optional for Android Watch device implementations.</p>
1972</div>
1973
1974
1975<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1976the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1977standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1978
1979<p>Android device implementations with H.264 decoders, MUST support Baseline
1980Profile Level 3 and the following SD video decoding profiles and SHOULD support
1981the HD decoding profiles. Android Television devices MUST support High Profile
1982Level 4.2 and the HD 1080p decoding profile.</p>
1983<table>
1984 <tr>
1985 <th></th>
1986 <th>SD (Low quality)</th>
1987 <th>SD (High quality)</th>
1988 <th>HD 720p1</th>
1989 <th>HD 1080p1</th>
1990 </tr>
1991 <tr>
1992 <th>Video resolution</th>
1993 <td>320 x 240 px</td>
1994 <td>720 x 480 px</td>
1995 <td>1280 x 720 px</td>
1996 <td>1920 x 1080 px</td>
1997 </tr>
1998 <tr>
1999 <th>Video frame rate</th>
2000 <td>30 fps</td>
2001 <td>30 fps</td>
2002 <td>30 fps / 60 fps2</td>
2003 <td>30 fps / 60 fps2</td>
2004 </tr>
2005 <tr>
2006 <th>Video bitrate</th>
2007 <td>800 Kbps </td>
2008 <td>2 Mbps</td>
2009 <td>8 Mbps</td>
2010 <td>20 Mbps</td>
2011 </tr>
2012</table>
2013
2014
2015<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2016types only when supported by hardware.</p>
2017
2018<p class="table_footnote">2 Required for Android Television device implementations.</p>
2019
2020<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
2021decoding profiles. Android Television devices MUST support the HD 1080p
2022decoding profile. </p>
2023<table>
2024 <tr>
2025 <th></th>
2026 <th>SD (Low quality)</th>
2027 <th>SD (High quality)</th>
2028 <th>HD 720p1</th>
2029 <th>HD 1080p1</th>
2030 </tr>
2031 <tr>
2032 <th>Video resolution</th>
2033 <td>320 x 180 px</td>
2034 <td>640 x 360 px</td>
2035 <td>1280 x 720 px</td>
2036 <td>1920 x 1080 px</td>
2037 </tr>
2038 <tr>
2039 <th>Video frame rate</th>
2040 <td>30 fps</td>
2041 <td>30 fps</td>
2042 <td>30 fps / 60 fps2</td>
2043 <td>30 / 60 fps2</td>
2044 </tr>
2045 <tr>
2046 <th>Video bitrate</th>
2047 <td>800 Kbps </td>
2048 <td>2 Mbps</td>
2049 <td>8 Mbps</td>
2050 <td>20 Mbps</td>
2051 </tr>
2052</table>
2053
2054
2055<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2056devices only when supported by hardware.</p>
2057
2058<p class="table_footnote">2 Required for Android Television device implementations.</p>
2059
2060<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
2061HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2062support the HD 1080p decoding profile and SHOULD support the UHD decoding
2063profile. When the UHD video decoding profile is supported, it MUST support 8
2064bit color depth.</p>
2065<table>
2066 <tr>
2067 <th></th>
2068 <th>SD (Low quality)</th>
2069 <th>SD (High quality)</th>
2070 <th>HD 720p 1</th>
2071 <th>HD 1080p 2</th>
2072 <th>UHD 2</th>
2073 </tr>
2074 <tr>
2075 <th>Video resolution</th>
2076 <td>320 x 180 px</td>
2077 <td>640 x 360 px</td>
2078 <td>1280 x 720 px</td>
2079 <td>1920 x 1080 px</td>
2080 <td>3840 x 2160 px</td>
2081 </tr>
2082 <tr>
2083 <th>Video frame rate</th>
2084 <td>30 fps</td>
2085 <td>30 fps</td>
2086 <td>30 fps</td>
2087 <td>30 fps</td>
2088 <td>30 fps</td>
2089 </tr>
2090 <tr>
2091 <th>Video bitrate</th>
2092 <td>600 Kbps </td>
2093 <td>1.6 Mbps</td>
2094 <td>4 Mbps</td>
2095 <td>10 Mbps</td>
2096 <td>20 Mbps</td>
2097 </tr>
2098</table>
2099
2100
2101<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2102devices only when supported by hardware.</p>
2103
2104<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2105supported by hardware.</p>
2106
2107<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
2108decoding profiles and SHOULD support the HD decoding profiles. Android
2109Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21101080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2111the UHD decoding profile.</p>
2112<table>
2113 <tr>
2114 <th></th>
2115 <th>SD (Low quality)</th>
2116 <th>SD (High quality)</th>
2117 <th>HD 720p </strong>1 </td>
2118 <th>HD 1080p </strong>1 </td>
2119 <th>UHD </strong>2</td>
2120 </tr>
2121 <tr>
2122 <th>Video resolution</th>
2123 <td>352 x 288 px</td>
2124 <td>640 x 360 px</td>
2125 <td>1280 x 720 px</td>
2126 <td>1920 x 1080 px</td>
2127 <td>3840 x 2160 px</td>
2128 </tr>
2129 <tr>
2130 <th>Video frame rate</th>
2131 <td>30 fps</td>
2132 <td>30 fps</td>
2133 <td>30 fps</td>
2134 <td>30 fps</td>
2135 <td>30 fps</td>
2136 </tr>
2137 <tr>
2138 <th>Video bitrate</th>
2139 <td>600 Kbps </td>
2140 <td>1.6 Mbps</td>
2141 <td>4 Mbps</td>
2142 <td>10 Mbps</td>
2143 <td>20 Mbps</td>
2144 </tr>
2145</table>
2146
2147
2148<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2149devices only when supported by hardware.</p>
2150
2151<p class="table_footnote">2 Required for Android Television device implementations when supported by
2152hardware.</p>
2153
2154<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2155
2156
2157<p>While some of the requirements outlined in this section are stated as SHOULD
2158since Android 4.3, the Compatibility Definition for a future version is planned
2159to 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
2160compatibility when upgraded to the future version.</p>
2161
2162<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2163
2164
2165<p>Device implementations that declare android.hardware.microphone MUST allow
2166capture of raw audio content with the following characteristics:</p>
2167
2168<ul>
2169 <li><strong>Format</strong>: Linear PCM, 16-bit
2170 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2171 <li><strong>Channels</strong>: Mono
2172</ul>
2173
2174<p>Device implementations that declare android.hardware.microphone SHOULD allow
2175capture of raw audio content with the following characteristics:</p>
2176
2177<ul>
2178 <li><strong>Format</strong>: Linear PCM, 16-bit
2179 <li><strong>Sampling rates</strong>: 22050, 48000
2180 <li><strong>Channels</strong>: Stereo
2181</ul>
2182
2183<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2184
2185
2186<p>In addition to the above recording specifications, when an application has
2187started recording an audio stream using the
2188android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2189
2190<ul>
2191 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2192characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2193 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2194source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2195 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2196dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2197 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2198level at the microphone.
2199 <li>Noise reduction processing, if present, MUST be disabled.
2200 <li>Automatic gain control, if present, MUST be disabled
2201</ul>
2202
2203<p>If the platform supports noise suppression technologies tuned for speech
2204recognition, the effect MUST be controllable from the
2205android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2206noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2207of the noise suppression technology.</p>
2208
2209<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2210
2211
2212<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2213audio source. Devices that declare android.hardware.audio.output MUST properly
2214implement the REMOTE_SUBMIX audio source so that when an application uses the
2215android.media.AudioRecord API to record from this audio source, it can capture
2216a mix of all audio streams except for the following:</p>
2217
2218<ul>
2219 <li>STREAM_RING
2220 <li>STREAM_ALARM
2221 <li>STREAM_NOTIFICATION
2222</ul>
2223
2224<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2225
2226
2227<p>Device implementations that declare android.hardware.audio.output MUST conform
2228to the requirements in this section.</p>
2229
2230<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2231
2232
2233<p>The device MUST allow playback of raw audio content with the following
2234characteristics:</p>
2235
2236<ul>
2237 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2238 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2239 <li><strong>Channels</strong>: Mono, Stereo</li>
2240</ul>
2241
2242<p>The device SHOULD allow playback of raw audio content with the following
2243characteristics:</p>
2244
2245<ul>
2246 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2247</ul>
2248
2249<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2250
2251
2252<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
2253android.hardware.audio.output:</p>
2254
2255<ul>
2256 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2257implementations controllable through the AudioEffect subclasses Equalizer,
2258LoudnessEnhancer.</li>
2259 <li>MUST support the visualizer API implementation, controllable through the
2260Visualizer class.</li>
2261 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2262EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2263controllable through the AudioEffect sub-classes BassBoost,
2264EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2265</ul>
2266
2267<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2268
2269
2270<p>Android Television device implementations MUST include support for system
2271Master Volume and digital audio output volume attenuation on supported outputs,
2272except for compressed audio passthrough output (where no audio decoding is done
2273on the device).</p>
2274
2275<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2276
2277
2278<p>Audio latency is the time delay as an audio signal passes through a system.
2279Many classes of applications rely on short latencies, to achieve real-time
2280sound effects.</p>
2281
2282<p>For the purposes of this section, use the following definitions:</p>
2283
2284<ul>
2285 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2286when the corresponding sound can be heard by an external listener or observed
2287by a transducer.</li>
2288 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2289idle and powered down prior to the request.</li>
2290 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2291 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2292when an application reads the corresponding frame of PCM-coded data.</li>
2293 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2294audio input system has been idle and powered down prior to the request.</li>
2295 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2296 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2297 <li><strong>cold input jitter</strong>. The variance among separate measurements of cold input latency values.</li>
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2298 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2299 one buffer period.
2300 The buffer period term allows processing time for the app and for the app to
2301 mitigate phase difference between input and output streams.
2302 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2303 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2304NDK_root/docs/opensles/index.html.</li>
2305</ul>
2306
2307<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2308or exceed these audio output requirements:</p>
2309
2310<ul>
2311 <li>cold output latency of 100 milliseconds or less</li>
2312 <li>continuous output latency of 45 milliseconds or less</li>
2313 <li>minimize the cold output jitter</li>
2314</ul>
2315
2316<p>If a device implementation meets the requirements of this section after any
2317initial calibration when using the OpenSL ES PCM buffer queue API, for
2318continuous output latency and cold output latency over at least one supported
2319audio output device, it MAY report support for low-latency audio, by reporting
2320the feature android.hardware.audio.low_latency via the
2321android.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
2322MUST NOT report support for low-latency audio.</p>
2323
2324<p>Device implementations that include android.hardware.microphone SHOULD meet
2325these input audio requirements:</p>
2326
2327<ul>
2328 <li>cold input latency of 100 milliseconds or less</li>
2329 <li>continuous input latency of 30 milliseconds or less</li>
2330 <li>continuous round-trip latency of 50 milliseconds or less</li>
2331 <li>minimize the cold input jitter</li>
2332</ul>
2333
2334<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2335
2336
2337<p>Devices MUST support the media network protocols for audio and video playback
2338as 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>
2339
2340<ul>
2341 <li>RTSP (RTP, SDP)</li>
2342 <li>HTTP(S) progressive streaming</li>
2343 <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>
2344</ul>
2345
2346<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2347
2348
2349<p>Device implementations that support secure video output and are capable of
2350supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2351implementations that declare support for Display.FLAG_SECURE, if they support a
2352wireless display protocol, MUST secure the link with a cryptographically strong
2353mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2354if they support a wired external display, the device implementations MUST
2355support HDCP 1.2 or higher. Android Television device implementations MUST
2356support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2357lower resolutions. The upstream Android open source implementation includes
2358support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2359requirement.</p>
2360
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2361<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2362
2363<p>
2364If a device implementation supports the inter-app MIDI software transport
2365(virtual MIDI devices), and it supports MIDI over
2366<em>all</em> of the following MIDI-capable hardware transports
2367for which it provides generic non-MIDI connectivity, it MAY report
2368support for feature android.software.midi via the
2369android.content.pm.PackageManager class
2370[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2371</p>
2372
2373<p>The MIDI-capable hardware transports are:</p>
2374<ul>
2375 <li>USB host mode (section 7.7 USB)</li>
2376 <li>USB peripheral mode (section 7.7 USB)</li>
2377</ul>
2378
2379<p>
2380Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2381MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2382it MUST NOT report support for feature android.software.midi.
2383</p>
2384
2385<p>
2386MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2387is in trial use status. A device implementation that reports
2388feature android.software.midi, and which provides generic non-MIDI connectivity
2389over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2390</p>
2391
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2392<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2393
2394<p>
2395If a device implementation meets <em>all</em> of the following requirements,
2396it MAY report support for feature android.hardware.audio.pro via the
2397android.content.pm.PackageManager class
2398[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2399</p>
2400
2401<ul>
2402
2403<li>
2404The device implementation MUST support android.hardware.audio.low_latency
2405</li>
2406
2407<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2408MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2409supported path.
2410</li>
2411
2412<li>
2413If the device implementation includes a 4 conductor 3.5mm audio jack,
2414the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2415and SHOULD be 10 milliseconds or less over at the audio jack path.
2416</li>
2417
2418<li>
2419The device implementation MUST include a USB port(s) supporting USB host mode and
2420USB peripheral mode.
2421</li>
2422
2423<li>
Glenn Kasten755f4b22015-09-25 16:04:23 -0700[diff] [blame^]2424The USB host mode MUST implement the USB audio class.
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2425</li>
2426
2427<li>
2428If the device includes an HDMI port, the device implementation
2429MUST support output in stereo and 8 channels
2430at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2431</li>
2432
2433<li>
2434The device implementation MUST report support for feature android.software.midi.
2435</li>
2436
2437</ul>
2438
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2439<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2440
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2441<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2442
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2443<p>Device implementations MUST support the Android Developer Tools provided in the
2444Android SDK. Android compatible devices MUST be compatible with:</p>
2445
2446<ul>
2447 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2448</ul>
2449
2450<p>Device implementations MUST support all adb functions as documented in the
2451Android 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
2452user-accessible mechanism to turn on the Android Debug Bridge. If a device
2453implementation omits USB peripheral mode, it MUST implement the Android Debug
2454Bridge via local-area network (such as Ethernet or 802.11). </p>
2455
2456<p>Android includes support for secure adb. Secure adb enables adb on known
2457authenticated hosts. Device implementations MUST support secure adb.</p>
2458
2459<ul>
2460 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2461</ul>
2462
2463<p>Device implementations MUST support all ddms features as documented in the
2464Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2465but MUST be supported whenever the user has activated the Android Debug Bridge,
2466as above.</p>
2467
2468<ul>
2469 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2470</ul>
2471
2472<p>Device implementations MUST include the Monkey framework, and make it available
2473for applications to use.</p>
2474
2475<ul>
2476 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2477</ul>
2478
2479<p>Device implementations MUST support systrace tool as documented in the Android
2480SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2481mechanism to turn on Systrace.</p>
2482
2483<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2484using the standard Android SDK tools, without additional support; however
2485Microsoft Windows systems typically require a driver for new Android devices.
2486(For instance, new vendor IDs and sometimes new device IDs require custom USB
2487drivers for Windows systems.) If a device implementation is unrecognized by the
2488adb tool as provided in the standard Android SDK, device implementers MUST
2489provide Windows drivers allowing developers to connect to the device using the
2490adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2491Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2492
2493<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2494
2495
2496<p>Android includes support for developers to configure application
2497development-related settings. Device implementations MUST honor the
2498android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2499development-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
2500default and enables users to launch Developer Options after pressing seven (7)
2501times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2502Developer Options. Specifically, device implementations MUST hide Developer
2503Options by default and MUST provide a mechanism to enable Developer Options
2504that is consistent with the upstream Android implementation.</p>
2505
2506<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2507
2508
2509<p>If a device includes a particular hardware component that has a corresponding
2510API for third-party developers, the device implementation MUST implement that
2511API as described in the Android SDK documentation. If an API in the SDK
2512interacts with a hardware component that is stated to be optional and the
2513device implementation does not possess that component:</p>
2514
2515<ul>
2516 <li>Complete class definitions (as documented by the SDK) for the component APIs
2517MUST still be presented.
2518 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2519 <li>API methods MUST return null values where permitted by the SDK documentation.
2520 <li>API methods MUST return no-op implementations of classes where null values are
2521not permitted by the SDK documentation.
2522 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2523</ul>
2524
2525<p>A typical example of a scenario where these requirements apply is the telephony
2526API: even on non-phone devices, these APIs must be implemented as reasonable
2527no-ops.</p>
2528
2529<p>Device implementations MUST consistently report accurate hardware configuration
2530information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2531methods on the android.content.pm.PackageManager class for the same build
2532fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2533
2534<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2535
2536
2537<p>Android includes facilities that automatically adjust application assets and UI
2538layouts appropriately for the device, to ensure that third-party applications
2539run 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
2540this section.</p>
2541
2542<p>The units referenced by the requirements in this section are defined as
2543follows:</p>
2544
2545<ul>
2546 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2547of the display.</li>
2548 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
25491&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2550within the range.</li>
2551 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2552 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2553 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2554 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2555dps * (density/160).</li>
2556</ul>
2557
2558<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2559
2560
2561<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2562
2563<div class="note">
2564<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>
2565</div>
2566
2567<p>The Android UI framework supports a variety of different screen sizes, and
2568allows applications to query the device screen size (aka &ldquo;screen layout") via
2569android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2570Device implementations MUST report the correct screen size as defined in the
2571Android 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
2572implementations MUST report the correct screen size according to the following
2573logical density-independent pixel (dp) screen dimensions.</p>
2574
2575<ul>
2576 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2577is an Android Watch device.</li>
2578 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2579dp x 320 dp.</li>
2580 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2581dp x 480 dp.</li>
2582 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2583dp x 720 dp.</li>
2584</ul>
2585
2586<p>In addition, </p>
2587
2588<ul>
2589 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2590range from 1.1 to 2.5 inches.</li>
2591 <li>Other types of Android device implementations, with a physically integrated
2592screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2593</ul>
2594
2595<p>Devices MUST NOT change their reported screen size at any time.</p>
2596
2597<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2598&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2599implementations MUST correctly honor applications' stated support for small,
2600normal, large, and xlarge screens, as described in the Android SDK
2601documentation.</p>
2602
2603<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2604
2605<div class="note">
2606<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2607</div>
2608
2609
2610<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
261116:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2612such a device implementation will use a UI_MODE_TYPE_WATCH as the
2613android.content.res.Configuration.uiMode.</p>
2614
2615<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2616
2617
2618<p>The Android UI framework defines a set of standard logical densities to help
2619application developers target application resources. Device implementations
2620MUST report only one of the following logical Android framework densities
2621through the android.util.DisplayMetrics APIs, and MUST execute applications at
2622this standard density and MUST NOT change the value at at any time for the
2623default display.</p>
2624
2625<ul>
2626 <li>120 dpi (ldpi)</li>
2627 <li>160 dpi (mdpi)</li>
2628 <li>213 dpi (tvdpi)</li>
2629 <li>240 dpi (hdpi)</li>
2630 <li>280 dpi (280dpi)</li>
2631 <li>320 dpi (xhdpi)</li>
2632 <li>400 dpi (400dpi)</li>
2633 <li>480 dpi (xxhdpi)</li>
2634 <li>560 dpi (560dpi)</li>
2635 <li>640 dpi (xxxhdpi)</li>
2636</ul>
2637
2638<p>Device implementations SHOULD define the standard Android framework density
2639that is numerically closest to the physical density of the screen, unless that
2640logical density pushes the reported screen size below the minimum supported. If
2641the standard Android framework density that is numerically closest to the
2642physical density results in a screen size that is smaller than the smallest
2643supported compatible screen size (320 dp width), device implementations SHOULD
2644report the next lowest standard Android framework density.</p>
2645
2646<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2647
2648
2649<p>Device implementations MUST report correct values for all display metrics
2650defined 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
2651external screen is used as the default display.</p>
2652
2653<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2654
2655
2656<p>Devices MUST report which screen orientations they support
2657(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2658MUST report at least one supported orientation. For example, a device with a
2659fixed orientation landscape screen, such as a television or laptop, SHOULD only
2660report android.hardware.screen.landscape.</p>
2661
2662<p>Devices that report both screen orientations MUST support dynamic orientation
2663by applications to either portrait or landscape screen orientation. That is,
2664the device must respect the application&rsquo;s request for a specific screen
2665orientation. Device implementations MAY select either portrait or landscape
2666orientation as the default.</p>
2667
2668<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2669whenever queried via the android.content.res.Configuration.orientation,
2670android.view.Display.getOrientation(), or other APIs.</p>
2671
2672<p>Devices MUST NOT change the reported screen size or density when changing
2673orientation.</p>
2674
2675<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2676
2677
2678<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2679detailed in the Android SDK documentations. Device implementations SHOULD
2680support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2681implementations MUST also support Android RenderScript, as detailed in the
2682Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2683
2684<p>Device implementations MUST also correctly identify themselves as supporting
2685OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2686
2687<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2688 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2689for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2690 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2691libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2692ES 2.0.</li>
2693 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2694support the corresponding managed APIs and include support for native C/C++
2695APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2696libGLESv2.so MUST export the corresponding function symbols in addition to the
2697OpenGL ES 2.0 function symbols.</li>
2698</ul>
2699
2700<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2701interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2702and the ASTC texture compression format. Android device implementations MAY
2703support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2704support through the android.hardware.opengles.aep feature flag.</p>
2705
2706<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2707However, device implementations MUST report via the OpenGL ES managed and
2708native APIs all extension strings that they do support, and conversely MUST NOT
2709report extension strings that they do not support.</p>
2710
2711<p>Note that Android includes support for applications to optionally specify that
2712they require specific OpenGL texture compression formats. These formats are
2713typically vendor-specific. Device implementations are not required by Android
2714to implement any specific texture compression format. However, they SHOULD
2715accurately report any texture compression formats that they do support, via the
2716getString() method in the OpenGL API.</p>
2717
2718<p>Android includes a mechanism for applications to declare that they want to
2719enable hardware acceleration for 2D graphics at the Application, Activity,
2720Window, or View level through the use of a manifest tag
2721android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2722
2723<p>Device implementations MUST enable hardware acceleration by default, and MUST
2724disable hardware acceleration if the developer so requests by setting
2725android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2726through the Android View APIs.</p>
2727
2728<p>In addition, device implementations MUST exhibit behavior consistent with the
2729Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2730
2731<p>Android includes a TextureView object that lets developers directly integrate
2732hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2733Device implementations MUST support the TextureView API, and MUST exhibit
2734consistent behavior with the upstream Android implementation.</p>
2735
2736<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2737that indicates whether the EGLConfig supports rendering to an ANativeWindow
2738that records images to a video. Device implementations MUST support
2739EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2740
2741<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2742
2743
2744<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2745'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2746applications not developed for old versions of Android that pre-date
2747screen-size independence.</p>
2748
2749<ul>
2750<li>Android Automotive does not support legacy compatibility mode.</li>
2751<li>All other device implementations MUST include support for legacy application
2752compatibility mode as implemented by the upstream Android open source code. That
2753is, device implementations MUST NOT alter the triggers or thresholds at which
2754compatibility mode is activated, and MUST NOT alter the behavior of the
2755compatibility mode itself.</li>
2756</ul>
2757
2758<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2759
2760
2761<p>The Android platform includes APIs that allow applications to render rich
2762graphics to the display. Devices MUST support all of these APIs as defined by
2763the Android SDK unless specifically allowed in this document. </p>
2764
2765<ul>
2766 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2767SHOULD support displays capable of 24-bit color graphics.</li>
2768 <li>Devices MUST support displays capable of rendering animations.</li>
2769 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2770and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
277115% tolerance.</li>
2772</ul>
2773
2774<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2775
2776
2777<p>Android includes support for secondary display to enable media sharing
2778capabilities and developer APIs for accessing external displays. If a device
2779supports an external display either via a wired, wireless, or an embedded
2780additional display connection then the device implementation MUST implement the
2781display 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>
2782
2783<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2784
2785<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2786for non-touch navigation.</p>
2787
2788<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2789
2790<div class="note">
2791<p>Android Watch and Android Automotive implementations MAY implement a soft
2792keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2793</div>
2794
2795
2796<p>Device implementations:</p>
2797
2798<ul>
2799 <li>MUST include support for the Input Management Framework (which allows
2800third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2801detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2802 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2803hard keyboard is present) except for Android Watch devices where the screen
2804size makes it less reasonable to have a soft keyboard.</li>
2805 <li>MAY include additional soft keyboard implementations.</li>
2806 <li>MAY include a hardware keyboard.</li>
2807 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2808specified 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>
2809</ul>
2810
2811<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2812
2813<div class="note">
2814<p>Android Television devices MUST support D-pad.</p>
2815</div>
2816
2817<p>Device implementations:</p>
2818
2819<ul>
2820 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2821device implementation is not an Android Television device.</li>
2822 <li>MUST report the correct value for android.content.res.Configuration.navigation
2823[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2824 <li>MUST provide a reasonable alternative user interface mechanism for the
2825selection and editing of text, compatible with Input Management Engines. The
2826upstream Android open source implementation includes a selection mechanism
2827suitable for use with devices that lack non-touch navigation inputs.</li>
2828</ul>
2829
2830<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2831
2832<div class="note">
2833<p>The availability and visibility requirement of the Home, Recents, and Back
2834functions differ between device types as described in this section.</p>
2835</div>
2836
2837<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2838KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2839navigation paradigm and therefore:</p>
2840
2841<ul>
2842 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2843Back functions.</li>
2844 <li>Android Television device implementations MUST provide the Home and Back
2845functions.</li>
2846 <li>Android Watch device implementations MUST have the Home function available to
2847the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2848 <li>Android Automotive implementations MUST provide the Home function and MAY
2849provide Back and Recent functions.</li>
2850 <li>All other types of device implementations MUST provide the Home and Back
2851functions.</li>
2852</ul>
2853
2854<p>These functions MAY be implemented via dedicated physical buttons (such as
2855mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2856software keys on a distinct portion of the screen, gestures, touch panel, etc.
2857Android supports both implementations. All of these functions MUST be
2858accessible with a single action (e.g. tap, double-click or gesture) when
2859visible.</p>
2860
2861<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2862together with other navigation functions in full-screen mode. This does not
2863apply to devices upgrading from earlier Android versions that have physical
2864buttons for navigation and no recents key.</p>
2865
2866<p> The Home and Back functions, if provided, MUST each have a visible button or
2867icon unless hidden together with other navigation functions in full-screen mode
2868or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2869
2870<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2871Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2872implement a dedicated physical button for the Menu function. Older device
2873implementations SHOULD NOT implement a dedicated physical button for the Menu
2874function, but if the physical Menu button is implemented and the device is
2875running applications with targetSdkVersion > 10, the device implementation:</p>
2876
2877<ul>
2878 <li>MUST display the action overflow button on the action bar when it is visible
2879and the resulting action overflow menu popup is not empty. For a device
2880implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2881is RECOMMENDED.</li>
2882 <li>MUST NOT modify the position of the action overflow popup displayed by
2883selecting the overflow button in the action bar.</li>
2884 <li>MAY render the action overflow popup at a modified position on the screen when
2885it is displayed by selecting the physical menu button.</li>
2886</ul>
2887
2888<p>For backwards compatibility, device implementations MUST make the Menu function
2889available to applications when targetSdkVersion is less than 10, either by a physical
2890button, a software key, or gestures. This Menu function should be presented
2891unless hidden together with other navigation functions.</p>
2892
2893<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
2894the Assist action available to the user at all times when running applications.
2895The Assist action SHOULD be implemented as a long-press on the Home button or a
2896swipe-up gesture on the software Home key. This function MAY be implemented via
2897another physical button, software key, or gesture, but MUST be accessible with
2898a single action (e.g. tap, double-click, or gesture) when other navigation keys
2899are visible.</p>
2900
2901<p>Device implementations MAY use a distinct portion of the screen to display the
2902navigation keys, but if so, MUST meet these requirements:</p>
2903
2904<ul>
2905 <li>Device implementation navigation keys MUST use a distinct portion of the
2906screen, not available to applications, and MUST NOT obscure or otherwise
2907interfere with the portion of the screen available to applications.</li>
2908 <li>Device implementations MUST make available a portion of the display to
2909applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2910 <li>Device implementations MUST display the navigation keys when applications do
2911not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2912 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2913profile&rdquo; (eg. dimmed) mode when applications specify
2914SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2915 <li>Device implementations MUST hide the navigation keys when applications specify
2916SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2917</ul>
2918
2919<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2920
2921<div class="note">
2922<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2923</div>
2924
2925
2926<p>Device implementations SHOULD have a pointer input system of some kind (either
2927mouse-like or touch). However, if a device implementation does not support a
2928pointer input system, it MUST NOT report the android.hardware.touchscreen or
2929android.hardware.faketouch feature constant. Device implementations that do
2930include a pointer input system:</p>
2931
2932<ul>
2933 <li>SHOULD support fully independently tracked pointers, if the device input system
2934supports multiple pointers.</li>
2935 <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>
2936</ul>
2937
2938<p>Android includes support for a variety of touchscreens, touch pads, and fake
2939touch input devices. Touchscreen based device implementations are associated
2940with 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
2941screen. Since the user is directly touching the screen, the system does not
2942require any additional affordances to indicate the objects being manipulated.
2943In contrast, a fake touch interface provides a user input system that
2944approximates a subset of touchscreen capabilities. For example, a mouse or
2945remote control that drives an on-screen cursor approximates touch, but requires
2946the user to first point or focus then click. Numerous input devices like the
2947mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2948trackpad can support fake touch interactions. Android includes the feature
2949constant android.hardware.faketouch, which corresponds to a high-fidelity
2950non-touch (pointer-based) input device such as a mouse or trackpad that can
2951adequately emulate touch-based input (including basic gesture support), and
2952indicates that the device supports an emulated subset of touchscreen
2953functionality. Device implementations that declare the fake touch feature MUST
2954meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2955
2956<p>Device implementations MUST report the correct feature corresponding to the
2957type of input used. Device implementations that include a touchscreen
2958(single-touch or better) MUST report the platform feature constant
2959android.hardware.touchscreen. Device implementations that report the platform
2960feature constant android.hardware.touchscreen MUST also report the platform
2961feature constant android.hardware.faketouch. Device implementations that do not
2962include a touchscreen (and rely on a pointer device only) MUST NOT report any
2963touchscreen feature, and MUST report only android.hardware.faketouch if they
2964meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2965
2966<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2967
2968
2969<p>Device implementations that declare support for android.hardware.faketouch:</p>
2970
2971<ul>
2972 <li>MUST report the absolute X and Y screen positions of the pointer location and
2973display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2974 <li>MUST report touch event with the action code that specifies the state change
2975that 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>
2976 <li>MUST support pointer down and up on an object on the screen, which allows users
2977to emulate tap on an object on the screen.</li>
2978 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2979place on an object on the screen within a time threshold, which allows users to
2980emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2981 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2982any other arbitrary point on the screen, followed by a pointer up, which allows
2983users to emulate a touch drag.</li>
2984 <li>MUST support pointer down then allow users to quickly move the object to a
2985different position on the screen and then pointer up on the screen, which
2986allows users to fling an object on the screen.</li>
2987</ul>
2988
2989<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2990MUST meet the requirements for faketouch above, and MUST also support distinct
2991tracking of two or more independent pointer inputs.</p>
2992
2993<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
2994
2995
2996<p>Android Television device implementations MUST support button mappings for game
2997controllers as listed below. The upstream Android implementation includes
2998implementation for game controllers that satisfies this requirement. </p>
2999
3000<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3001
3002
3003<p>Android Television device implementations MUST support the following key
3004mappings:</p>
3005<table>
3006 <tr>
3007 <th>Button</th>
3008 <th>HID Usage</strong><sup>2</sup></td>
3009 <th>Android Button</th>
3010 </tr>
3011 <tr>
3012 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3013 <td>0x09 0x0001</td>
3014 <td>KEYCODE_BUTTON_A (96)</td>
3015 </tr>
3016 <tr>
3017 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3018 <td>0x09 0x0002</td>
3019 <td>KEYCODE_BUTTON_B (97)</td>
3020 </tr>
3021 <tr>
3022 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3023 <td>0x09 0x0004</td>
3024 <td>KEYCODE_BUTTON_X (99)</td>
3025 </tr>
3026 <tr>
3027 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3028 <td>0x09 0x0005</td>
3029 <td>KEYCODE_BUTTON_Y (100)</td>
3030 </tr>
3031 <tr>
3032 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
3033
3034<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]3035 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3036 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3037 </tr>
3038 <tr>
3039 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3040
3041<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]3042 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3043 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3044 </tr>
3045 <tr>
3046 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3047 <td>0x09 0x0007</td>
3048 <td>KEYCODE_BUTTON_L1 (102)</td>
3049 </tr>
3050 <tr>
3051 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3052 <td>0x09 0x0008</td>
3053 <td>KEYCODE_BUTTON_R1 (103)</td>
3054 </tr>
3055 <tr>
3056 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3057 <td>0x09 0x000E</td>
3058 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3059 </tr>
3060 <tr>
3061 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3062 <td>0x09 0x000F</td>
3063 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3064 </tr>
3065 <tr>
3066 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3067 <td>0x0c 0x0223</td>
3068 <td>KEYCODE_HOME (3)</td>
3069 </tr>
3070 <tr>
3071 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3072 <td>0x0c 0x0224</td>
3073 <td>KEYCODE_BACK (4)</td>
3074 </tr>
3075</table>
3076
3077
3078<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3079
3080<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3081
3082<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3083Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3084Report Size of 4. The logical value is defined to be the clockwise rotation
3085away from the vertical axis; for example, a logical value of 0 represents no
3086rotation and the up button being pressed, while a logical value of 1 represents
3087a rotation of 45 degrees and both the up and left keys being pressed.</p>
3088
3089<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3090
3091<table>
3092 <tr>
3093 <th>Analog Controls</strong><sup>1</sup></td>
3094 <th>HID Usage</th>
3095 <th>Android Button</th>
3096 </tr>
3097 <tr>
3098 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3099 <td>0x02 0x00C5</td>
3100 <td>AXIS_LTRIGGER </td>
3101 </tr>
3102 <tr>
3103 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3104 <td>0x02 0x00C4</td>
3105 <td>AXIS_RTRIGGER </td>
3106 </tr>
3107 <tr>
3108 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3109 <td>0x01 0x0030</p>
3110
3111<p>0x01 0x0031</td>
3112 <td>AXIS_X</p>
3113
3114<p>AXIS_Y</td>
3115 </tr>
3116 <tr>
3117 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3118 <td>0x01 0x0032</p>
3119
3120<p>0x01 0x0035</td>
3121 <td>AXIS_Z</p>
3122
3123<p>AXIS_RZ</td>
3124 </tr>
3125</table>
3126
3127
3128<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3129
3130<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3131
3132
3133<p>Android Television device implementations SHOULD provide a remote control to
3134allow users to access the TV interface. The remote control MAY be a physical
3135remote or can be a software-based remote that is accessible from a mobile phone
3136or tablet. The remote control MUST meet the requirements defined below.</p>
3137
3138<ul>
3139 <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>
3140 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3141support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3142</ul>
3143
3144<h2 id="7_3_sensors">7.3. Sensors</h2>
3145
3146
3147<p>Android includes APIs for accessing a variety of sensor types. Devices
3148implementations generally MAY omit these sensors, as provided for in the
3149following subsections. If a device includes a particular sensor type that has a
3150corresponding API for third-party developers, the device implementation MUST
3151implement that API as described in the Android SDK documentation and the
3152Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3153
3154<ul>
3155 <li>MUST accurately report the presence or absence of sensors per the
3156android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3157 <li>MUST return an accurate list of supported sensors via the
3158SensorManager.getSensorList() and similar methods.</li>
3159 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3160true or false as appropriate when applications attempt to register listeners,
3161not calling sensor listeners when the corresponding sensors are not present;
3162etc.).</li>
3163 <li>MUST report all sensor measurements using the relevant International System of
3164Units (metric) values for each sensor type as defined in the Android SDK
3165documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3166 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3167documentation, representing the time the event happened and synchronized with
3168the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3169are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3170platform releases where this might become a REQUIRED component. The
3171synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3172</ul>
3173
3174<p>The list above is not comprehensive; the documented behavior of the Android SDK
3175and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3176
3177<p>Some sensor types are composite, meaning they can be derived from data provided
3178by one or more other sensors. (Examples include the orientation sensor, and the
3179linear acceleration sensor.) Device implementations SHOULD implement these
3180sensor types, when they include the prerequisite physical sensors as described
3181in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3182If a device implementation includes a composite sensor it MUST implement the
3183sensor as described in the Android Open Source documentation on composite
3184sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3185
3186<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3187continuously [<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
3188sensor, device implementations MUST continuously provide periodic data samples
3189that SHOULD have a jitter below 3%, where jitter is defined as the standard
3190deviation of the difference of the reported timestamp values between
3191consecutive events.</p>
3192
3193<p>Note that the device implementations MUST ensure that the sensor event stream
3194MUST NOT prevent the device CPU from entering a suspend state or waking up from
3195a suspend state.</p>
3196
3197<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3198exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3199
3200<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3201
3202
3203<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3204devices and Android Watch devices are strongly encouraged to include this
3205sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3206
3207<ul>
3208 <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>
3209 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3210 Android Watch devices as such devices have a stricter power constraint and
3211 100 Hz for all other device types.</li>
3212 <li>SHOULD report events up to at least 200 Hz.</li>
3213 <li>MUST comply with the Android sensor coordinate system as detailed in the
3214Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3215 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3216more on any axis.</li>
3217 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3218least 16-bits.</li>
3219 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3220cycle and compensated, and preserve the compensation parameters between device
3221reboots.</li>
3222 <li>SHOULD be temperature compensated.</li>
3223 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3224deviation should be calculated on a per axis basis on samples collected over a
3225period of at least 3 seconds at the fastest sampling rate.</li>
3226 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3227TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3228Android 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
3229sensors are implemented, the sum of their power consumption MUST always be less
3230than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3231dynamic or static condition.</li>
3232 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3233TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3234TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3235are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3236 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3237and a magnetometer sensor is also included.</li>
3238</ul>
3239
3240<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3241
3242
3243<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3244device does include a 3-axis magnetometer, it:</p>
3245
3246<ul>
3247 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3248TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3249strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3250 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3251report events up to at least 50 Hz.</li>
3252 <li>MUST comply with the Android sensor coordinate system as detailed in the
3253Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3254 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3255saturating.</li>
3256 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3257below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3258and static (magnet-induced) magnetic fields.</li>
3259 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3260equal or denser than 0.2 &micro;.</li>
3261 <li>SHOULD be temperature compensated.</li>
3262 <li>MUST support online calibration and compensation of the hard iron bias, and
3263preserve the compensation parameters between device reboots.</li>
3264 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3265while in use or during the production of the device.</li>
3266 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3267collected over a period of at least 3 seconds at the fastest sampling rate, no
3268greater than 0.5 &micro;T.</li>
3269 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3270sensor and a gyroscope sensor is also included.</li>
3271 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3272sensor is also implemented. However if implemented, it MUST consume less than
327310 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3274mode at 10 Hz.</li>
3275</ul>
3276
3277<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3278
3279
3280<p>Device implementations SHOULD include a GPS receiver. If a device
3281implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3282
3283<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3284
3285
3286<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3287Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3288also included. If a device implementation includes a gyroscope, it:</p>
3289
3290<ul>
3291 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3292TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3293strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3294 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3295 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3296 Android Watch devices as such devices have a stricter power constraint and
3297 100 Hz for all other device types.</li>
3298 <li>SHOULD report events up to at least 200 Hz.</li>
3299 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
330016-bits or more.</li>
3301 <li>MUST be temperature compensated.</li>
3302 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3303parameters between device reboots.</li>
3304 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3305or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3306be constrained by this value. In other words, if you measure the variance of
3307the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3308 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3309sensor and a magnetometer sensor is also included.</li>
3310 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3311TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3312TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3313are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3314</ul>
3315
3316<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3317
3318
3319<p>Device implementations SHOULD include a barometer (ambient air pressure
3320sensor). If a device implementation includes a barometer, it:</p>
3321
3322<ul>
3323 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3324 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3325 <li>MUST have adequate precision to enable estimating altitude.</li>
3326 <li>MUST be temperature compensated.</li>
3327</ul>
3328
3329<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3330
3331
3332<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3333If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3334measure the ambient (room) temperature in degrees Celsius.</p>
3335
3336<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3337present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3338temperature of the device CPU, and it MUST NOT measure any other temperature.
3339Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3340
3341<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3342
3343
3344<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3345
3346<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3347
3348
3349<p>Device implementations MAY include a proximity sensor. Devices that can make a
3350voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3351SHOULD include a proximity sensor. If a device implementation does include a
3352proximity sensor, it:</p>
3353
3354<ul>
3355 <li>MUST measure the proximity of an object in the same direction as the screen.
3356That is, the proximity sensor MUST be oriented to detect objects close to the
3357screen, as the primary intent of this sensor type is to detect a phone in use
3358by the user. If a device implementation includes a proximity sensor with any
3359other orientation, it MUST NOT be accessible through this API.</li>
3360 <li>MUST have 1-bit of accuracy or more.</li>
3361</ul>
3362
3363<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3364
3365
3366<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3367
3368
3369<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3370to hardware related to placing voice calls and sending SMS messages via a GSM
3371or CDMA network. While these voice calls may or may not be packet-switched,
3372they are for the purposes of Android considered independent of any data
3373connectivity that may be implemented using the same network. In other words,
3374the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3375calls and SMS. For instance, device implementations that cannot place calls or
3376send/receive SMS messages MUST NOT report the android.hardware.telephony
3377feature or any subfeatures, regardless of whether they use a cellular network
3378for data connectivity.</p>
3379
3380<p>Android MAY be used on devices that do not include telephony hardware. That is,
3381Android is compatible with devices that are not phones. However, if a device
3382implementation does include GSM or CDMA telephony, it MUST implement full
3383support for the API for that technology. Device implementations that do not
3384include telephony hardware MUST implement the full APIs as no-ops.</p>
3385
3386<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3387
3388<div class="note">
3389<p>Android Television device implementations MUST include Wi-Fi support.</p>
3390</div>
3391
3392
3393<p>Android Television device implementations MUST include support for one or more
3394forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3395implementation SHOULD include support for one or more forms of 802.11. If a
3396device implementation does include support for 802.11 and exposes the
3397functionality to a third-party application, it MUST implement the corresponding
3398Android API and:</p>
3399
3400<ul>
3401 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3402 <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>
3403 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3404(224.0.0.251) at any time of operation including when the screen is not in an
3405active state.</li>
3406</ul>
3407
3408<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3409
3410
3411<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3412peer-to-peer). If a device implementation does include support for Wi-Fi
3413Direct, it MUST implement the corresponding Android API as described in the SDK
3414documentation [<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>
3415
3416<ul>
3417 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3418 <li>MUST support regular Wi-Fi operation.</li>
3419 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3420</ul>
3421
3422<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3423
3424<div class="note">
3425<p>Android Television device implementations MUST include support for Wi-Fi
3426Tunneled Direct Link Setup (TDLS).</p>
3427</div>
3428
3429
3430<p>Android Television device implementations MUST include support for Wi-Fi
3431Tunneled Direct Link Setup (TDLS) and other types of Android device
3432implementations SHOULD include support for Wi-Fi TDLS as described in the
3433Android 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
3434by the WiFiManager API, the device:</p>
3435
3436<ul>
3437 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3438 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3439than going through the Wi-Fi access point.</li>
3440</ul>
3441
3442<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3443
3444<div class="note">
3445<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3446Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3447</div>
3448
3449
3450<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
3451Energy MUST declare the relevant platform features (android.hardware.bluetooth
3452and android.hardware.bluetooth_le respectively) and implement the platform
3453APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3454as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3455device implementations MUST support Bluetooth and Bluetooth LE. </p>
3456
3457<p>Device implementations including support for Bluetooth Low Energy:</p>
3458
3459<ul>
3460 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3461 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3462described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3463 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3464implementing 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
3465android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3466 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3467if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3468android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3469 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3470MUST report &lsquo;false&rsquo; whenever queried via the
3471android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3472</ul>
3473
3474<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3475
3476
3477<p>Device implementations SHOULD include a transceiver and related hardware for
3478Near-Field Communications (NFC). If a device implementation does include NFC
3479hardware and plans to make it available to third-party apps, then it:</p>
3480
3481<ul>
3482 <li>MUST report the android.hardware.nfc feature from the
3483android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3484 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3485standards:
3486 <ul>
3487 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3488Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3489following NFC standards:
3490 <ul>
3491 <li>NfcA (ISO14443-3A)</li>
3492 <li>NfcB (ISO14443-3B)</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3493 <li>NfcF (JIS X 6319-4)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3494 <li>IsoDep (ISO 14443-4)</li>
3495 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3496 </ul>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3497 <li>MUST be capable of reading and writing NDEF messages as well as raw
3498 data via the following NFC standards:</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3499 <ul>
3500 <li>NfcV (ISO 15693)</li>
3501 </ul></li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3502 <li>SHOULD be capable of reading the barcode and URL (if encoded) of
3503 Thinfilm NFC Barcode
3504 [<a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">Resources, XX</a>] products.
3505 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3506 <li>MUST be capable of transmitting and receiving data via the following
3507peer-to-peer standards and protocols:
3508 <ul>
3509 <li>ISO 18092</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3510 <li>LLCP 1.2 (defined by the NFC Forum)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3511 <li>SDP 1.0 (defined by the NFC Forum)</li>
3512 <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>
3513 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3514 </ul></li>
3515 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3516 <ul>
3517 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3518default SNEP server MUST be dispatched to applications using the
3519android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3520MUST NOT disable dispatch of incoming NDEF message.</li>
3521 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3522settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3523 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3524processed the same way as the SNEP default server.</li>
3525 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3526default SNEP server when Android Beam is enabled. If no default SNEP server is
3527found then the client MUST attempt to send to an NPP server.</li>
3528 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3529android.nfc.NfcAdapter.setNdefPushMessage, and
3530android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3531android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3532 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3533sending outbound P2P NDEF messages.</li>
3534 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3535using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3536 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3537Bluetooth Object Push Profile. Device implementations MUST support connection
3538handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3539implementing 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
3540LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3541handover request/select records over NFC, and it MUST use the Bluetooth Object
3542Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3543remain compatible with Android 4.1 devices), the implementation SHOULD still
3544accept SNEP GET requests for exchanging the handover request/select records
3545over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3546for performing connection handover.</li>
3547 </ul></li>
3548 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3549 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3550active and the lock-screen unlocked.</li>
3551</ul>
3552</ul>
3553
3554<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3555Forum specifications cited above.)</p>
3556
3557<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3558device implementation does include an NFC controller chipset capable of HCE and
3559Application ID (AID) routing, then it:</p>
3560
3561<ul>
3562 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3563 <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>
3564</ul>
3565
3566<p>Additionally, device implementations MAY include reader/writer support for the
3567following MIFARE technologies.</p>
3568
3569<ul>
3570 <li>MIFARE Classic</li>
3571 <li>MIFARE Ultralight</li>
3572 <li>NDEF on MIFARE Classic</li>
3573</ul>
3574
3575<p>Note that Android includes APIs for these MIFARE types. If a device
3576implementation supports MIFARE in the reader/writer role, it:</p>
3577
3578<ul>
3579 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3580 <li>MUST report the feature com.nxp.mifare from the
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3581android.content.pm.PackageManager.hasSystemFeature() method <a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">[Resources, 53]</a>. Note that this is not a standard Android feature and as such does not appear
3582as a constant in the android.content.pm.PackageManager class.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3583 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3584feature unless it also implements general NFC support as described in this
3585section.</li>
3586</ul>
3587
3588<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3589the android.hardware.nfc feature from the
3590android.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>
3591
3592<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3593protocol-independent data representation format, device implementations MUST
3594implement these APIs even if they do not include support for NFC or declare the
3595android.hardware.nfc feature.</p>
3596
3597<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3598
3599
3600<p>Device implementations MUST include support for one or more forms of data
3601networking. Specifically, device implementations MUST include support for at
3602least one data standard capable of 200Kbit/sec or greater. Examples of
3603technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3604Ethernet, Bluetooth PAN, etc.</p>
3605
3606<p>Device implementations where a physical networking standard (such as Ethernet)
3607is the primary data connection SHOULD also include support for at least one
3608common wireless data standard, such as 802.11 (Wi-Fi).</p>
3609
3610<p>Devices MAY implement more than one form of data connectivity.</p>
3611
3612<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3613
3614
3615<p>Device implementations MUST have the master auto-sync setting on by default so
3616that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3617
3618<h2 id="7_5_cameras">7.5. Cameras</h2>
3619
3620
3621<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3622front-facing camera. A rear-facing camera is a camera located on the side of
3623the device opposite the display; that is, it images scenes on the far side of
3624the device, like a traditional camera. A front-facing camera is a camera
3625located on the same side of the device as the display; that is, a camera
3626typically used to image the user, such as for video conferencing and similar
3627applications.</p>
3628
3629<p>If a device implementation includes at least one camera, it SHOULD be possible
3630for an application to simultaneously allocate 3 bitmaps equal to the size of
3631the images produced by the largest-resolution camera sensor on the device.</p>
3632
3633<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3634
3635
3636<p>Device implementations SHOULD include a rear-facing camera. If a device
3637implementation includes at least one rear-facing camera, it:</p>
3638
3639<ul>
3640 <li>MUST report the feature flag android.hardware.camera and
3641android.hardware.camera.any.</li>
3642 <li>MUST have a resolution of at least 2 megapixels.</li>
3643 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3644the camera driver (transparent to application software).</li>
3645 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3646 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3647lit while an android.hardware.Camera.PreviewCallback instance has been
3648registered on a Camera preview surface, unless the application has explicitly
3649enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3650of a Camera.Parameters object. Note that this constraint does not apply to the
3651device&rsquo;s built-in system camera application, but only to third-party
3652applications using Camera.PreviewCallback.</li>
3653</ul>
3654
3655<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3656
3657
3658<p>Device implementations MAY include a front-facing camera. If a device
3659implementation includes at least one front-facing camera, it:</p>
3660
3661<ul>
3662 <li>MUST report the feature flag android.hardware.camera.any and
3663android.hardware.camera.front.</li>
3664 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3665 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3666camera API in Android has specific support for front-facing cameras and device
3667implementations MUST NOT configure the API to to treat a front-facing camera as
3668the default rear-facing camera, even if it is the only camera on the device.</li>
3669 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3670cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3671 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3672CameraPreview, as follows:
3673 <ul>
3674 <li>If the device implementation is capable of being rotated by user (such as
3675automatically via an accelerometer or manually via user input), the camera
3676preview MUST be mirrored horizontally relative to the device&rsquo;s current
3677orientation.</li>
3678 <li>If the current application has explicitly requested that the Camera display be
3679rotated 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
3680orientation specified by the application.</li>
3681 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3682axis.</li>
3683 </ul></li>
3684 <li>MUST mirror the image displayed by the postview in the same manner as the
3685camera preview image stream. If the device implementation does not support
3686postview, this requirement obviously does not apply.</li>
3687 <li>MUST NOT mirror the final captured still image or video streams returned to
3688application callbacks or committed to media storage.</li>
3689</ul>
3690
3691<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3692
3693
3694<p>Device implementations with USB host mode MAY include support for an external
3695camera that connects to the USB port. If a device includes support for an
3696external camera, it:</p>
3697
3698<ul>
3699 <li>MUST declare the platform feature android.hardware.camera.external and
3700android.hardware camera.any.</li>
3701 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3702 <li>MAY support multiple cameras.</li>
3703</ul>
3704
3705<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3706high-quality unencoded streams (i.e. raw or independently compressed picture
3707streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3708unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3709device implementation.</p>
3710
3711<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3712
3713
3714<p>Android includes two API packages to access the camera, the newer
3715android.hardware.camera2 API expose lower-level camera control to the app,
3716including efficient zero-copy burst/streaming flows and per-frame controls of
3717exposure, gain, white balance gains, color conversion, denoising, sharpening,
3718and more.</p>
3719
3720<p>The older API package, android.hardware.Camera, is marked as deprecated in
3721Android 5.0 but as it should still be available for apps to use Android device
3722implementations MUST ensure the continued support of the API as described in
3723this section and in the Android SDK.</p>
3724
3725<p>Device implementations MUST implement the following behaviors for the
3726camera-related APIs, for all available cameras:</p>
3727
3728<ul>
3729 <li>If an application has never called
3730android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3731use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3732application callbacks.</li>
3733 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3734and the system calls the onPreviewFrame() method when the preview format is
3735YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3736be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3737 <li>For android.hardware.Camera, device implementations MUST support the YV12
3738format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3739camera previews for both front- and rear-facing cameras. (The hardware video
3740encoder and camera may use any native pixel format, but the device
3741implementation MUST support conversion to YV12.)</li>
3742 <li>For android.hardware.camera2, device implementations must support the
3743android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3744formats as outputs through the android.media.ImageReader API.</li>
3745</ul>
3746
3747<p>Device implementations MUST still implement the full Camera API included in the
3748Android 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
3749capabilities. For instance, cameras that lack autofocus MUST still call any
3750registered android.hardware.Camera.AutoFocusCallback instances (even though
3751this has no relevance to a non-autofocus camera.) Note that this does apply to
3752front-facing cameras; for instance, even though most front-facing cameras do
3753not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3754
3755<p>Device implementations MUST recognize and honor each parameter name defined as
3756a constant on the android.hardware.Camera.Parameters class, if the underlying
3757hardware supports the feature. If the device hardware does not support a
3758feature, the API must behave as documented. Conversely, device implementations
3759MUST NOT honor or recognize string constants passed to the
3760android.hardware.Camera.setParameters() method other than those documented as
3761constants on the android.hardware.Camera.Parameters. That is, device
3762implementations MUST support all standard Camera parameters if the hardware
3763allows, and MUST NOT support custom Camera parameter types. For instance,
3764device implementations that support image capture using high dynamic range
3765(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>
3766
3767<p>Because not all device implementations can fully support all the features of
3768the android.hardware.camera2 API, device implementations MUST report the proper
3769level of support with the android.info.supportedHardwareLevel property as
3770described 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>
3771
3772<p>Device implementations MUST also declare its Individual camera capabilities of
3773android.hardware.camera2 via the android.request.availableCapabilities property
3774and 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>
3775
3776<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3777whenever a new picture is taken by the camera and the entry of the picture has
3778been added to the media store.</p>
3779
3780<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3781whenever a new video is recorded by the camera and the entry of the picture has
3782been added to the media store.</p>
3783
3784<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3785
3786
3787<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3788long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3789when the device is held in the landscape orientation, cameras MUST capture
3790images in the landscape orientation. This applies regardless of the device&rsquo;s
3791natural orientation; that is, it applies to landscape-primary devices as well
3792as portrait-primary devices.</p>
3793
3794<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3795
3796
3797<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3798
3799<div class="note">
3800<p>Android Television devices MUST have at least 5GB of non-volatile storage
3801available for application private data.</p>
3802</div>
3803
3804
3805<p>The memory available to the kernel and userspace on device implementations MUST
3806be at least equal or larger than the minimum values specified by the following
3807table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3808<table>
3809 <tr>
3810 <th>Density and screen size</th>
3811 <th>32-bit device</th>
3812 <th>64-bit device</th>
3813 </tr>
3814 <tr>
3815 <td>Android Watch devices (due to smaller screens)</td>
3816 <td>416MB</td>
3817 <td>Not applicable</td>
3818 </tr>
3819 <tr>
3820 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3821 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3822 <li class="table_list">mdpi or lower on large screens</li>
3823 <li class="table_list">ldpi or lower on extra large screens</li>
3824 </ul></td>
3825 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3826 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3827 </tr>
3828 <tr>
3829 <td><ul>
3830 <li class="table_list">xhdpi or higher on small/normal screens</li>
3831 <li class="table_list">hdpi or higher on large screens</li>
3832 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3833 <td>512MB</td>
3834 <td>832MB</td>
3835 </tr>
3836 <tr>
3837 <td><ul>
3838 <li class="table_list">400dpi or higher on small/normal screens</li>
3839 <li class="table_list">xhdpi or higher on large screens</li>
3840 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3841 <td>896MB</td>
3842 <td>1280MB</td>
3843 </tr>
3844 <tr>
3845 <td><ul>
3846 <li class="table_list">560dpi or higher on small/normal screens</li>
3847 <li class="table_list">400dpi or higher on large screens</li>
3848 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3849 <td>1344MB</td>
3850 <td>1824MB</td>
3851 </tr>
3852</table>
3853
3854
3855<p>The minimum memory values MUST be in addition to any memory space already
3856dedicated to hardware components such as radio, video, and so on that is not
3857under the kernel&rsquo;s control.</p>
3858
3859<p>Device implementations with less than 512MB of memory available to the kernel
3860and userspace, unless an Android Watch, MUST return the value "true" for
3861ActivityManager.isLowRamDevice().</p>
3862
3863<p>Android Television devices MUST have at least 5GB and other device
3864implementations MUST have at least 1.5GB of non-volatile storage available for
3865application private data. That is, the /data partition MUST be at least 5GB for
3866Android Television devices and at least 1.5GB for other device implementations.
3867Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3868they will be able to upgrade to the future platform releases.</p>
3869
3870<p>The Android APIs include a Download Manager that applications MAY use to
3871download 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
3872downloading individual files of at least 100MB in size to the default &ldquo;cache"
3873location.</p>
3874
3875<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3876
3877
3878<p>Device implementations MUST offer shared storage for applications also often
3879referred as &ldquo;shared external storage&rdquo;. </p>
3880
3881<p>Device implementations MUST be configured with shared storage mounted by
3882default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3883path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3884to the actual mount point.</p>
3885
3886<p>Device implementations MAY have hardware for user-accessible removable storage,
3887such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3888shared storage requirement, the device implementation:</p>
3889
3890<ul>
3891 <li>MUST implement a toast or pop-up user interface warning the user when there is
3892no SD card.</li>
3893 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3894and other material available at time of purchase that the SD card has to be
3895separately purchased.</li>
3896 <li>MUST mount the SD card by default.</li>
3897</ul>
3898
3899<p>Alternatively, device implementations MAY allocate internal (non-removable)
3900storage as shared storage for apps as included in the upstream Android Open
3901Source Project; device implementations SHOULD use this configuration and
3902software implementation. If a device implementation uses internal
3903(non-removable) storage to satisfy the shared storage requirement, that storage
3904MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3905symbolic link to the physical location if it is mounted elsewhere).</p>
3906
3907<p>Device implementations MUST enforce as documented the
3908android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3909Shared storage MUST otherwise be writable by any application that obtains that
3910permission.</p>
3911
3912<p>Device implementations that include multiple shared storage paths (such as both
3913an SD card slot and shared internal storage) MUST NOT allow Android
3914applications to write to the secondary external storage, except for their
3915package-specific directories on the secondary external storage, but SHOULD
3916expose content from both storage paths transparently through Android&rsquo;s media
3917scanner service and android.provider.MediaStore.</p>
3918
3919<p>Regardless of the form of shared storage used, if the device implementation
3920has a USB port with USB peripheral mode support, it MUST provide some mechanism
3921to access the contents of shared storage from a host computer. Device
3922implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3923to satisfy this requirement. If the device implementation supports Media
3924Transfer Protocol, it:</p>
3925
3926<ul>
3927 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3928[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3929 <li>SHOULD report a USB device class of 0x00.</li>
3930 <li>SHOULD report a USB interface name of 'MTP'.</li>
3931</ul>
3932
3933<h2 id="7_7_usb">7.7. USB</h2>
3934
3935
3936<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3937USB host mode.</p>
3938
3939<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3940
3941<ul>
3942 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3943-C USB port.</li>
3944 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3945new 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>
3946 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3947SHOULD either locate the port on the bottom of the device (according to natural
3948orientation) or enable software screen rotation for all apps (including home
3949screen), so that the display draws correctly when the device is oriented with
3950the 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>
3951 <li>It MUST allow a USB host connected with the Android device to access the
3952contents of the shared storage volume using either USB mass storage or Media
3953Transfer Protocol.</li>
3954 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3955documented in the Android SDK documentation, and if it is an Android Handheld
3956device it MUST implement the AOA API. Device implementations implementing the
3957AOA specification:
3958 <ul>
3959 <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>
3960 <li>MUST implement the USB audio class as documented in the Android SDK
3961documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3962 </ul></li>
3963 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3964as 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>
3965 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3966the value of android.os.Build.SERIAL.</li>
3967</ul>
3968
3969<p>If a device implementation includes a USB port supporting host mode, it:</p>
3970
3971<ul>
3972 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3973 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3974cables adapting the port to a standard type-A or type-C USB port.</li>
3975 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3976adapting the port to a standard type-A or type-C USB port.</li>
3977 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3978documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3979 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3980MUST 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>
3981 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3982as 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>
3983</ul>
3984
3985<h2 id="7_8_audio">7.8. Audio</h2>
3986
3987
3988<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3989
3990<div class="note">
3991<p>Android Handheld, Watch, and Automotive implementations MUST include a
3992microphone.</p>
3993</div>
3994
3995
3996<p>Device implementations MAY omit a microphone. However, if a device
3997implementation omits a microphone, it MUST NOT report the
3998android.hardware.microphone feature constant, and MUST implement the audio
3999recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4000
4001<ul>
4002 <li>MUST report the android.hardware.microphone feature constant
4003 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
4004 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
4005</ul>
4006
4007<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4008
4009<div class="note">
4010<p>Android Watch devices MAY include an audio output.</p>
4011</div>
4012
4013<p>Device implementations including a speaker or with an audio/multimedia output
4014port for an audio output peripheral as a headset or an external speaker:</p>
4015
4016<ul>
4017 <li>MUST report the android.hardware.audio.output feature constant.</li>
4018 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4019 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4020</ul>
4021
4022<p>Conversely, if a device implementation does not include a speaker or audio
4023output port, it MUST NOT report the android.hardware.audio output feature, and
4024MUST implement the Audio Output related APIs as no-ops at least. </p>
4025
4026<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4027other types of Android device implementations MUST have an audio output and
4028declare android.hardware.audio.output.</p>
4029
4030<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4031
4032
4033<p>In order to be compatible with the headsets and other audio accessories using
4034the 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
4035one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4036implementation has a 4 conductor 3.5mm audio jack, it:</p>
4037
4038<ul>
4039 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4040microphone, and SHOULD support audio recording from stereo headsets with a
4041microphone.</li>
4042 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4043audio plugs with the OMTP pin-out order.</li>
4044 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4045the device implementation supports a microphone, and broadcast the
4046android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4047 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4048ranges of equivalent impedance between the microphone and ground conductors on
4049the audio plug:
4050 <ul>
4051 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4052 <li><strong>210&#45;290 Ohm</strong>: KEYCODE_VOLUME_UP</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4053 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4054 </ul></li>
4055 <li>SHOULD support the detection and mapping to the keycode for the following range
4056of equivalent impedance between the microphone and ground conductors on the
4057audio plug:
4058 <ul>
4059 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4060 </ul></li>
4061 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4062contacts on plug are touching their relevant segments on the jack.</li>
4063 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4064speaker impedance.</li>
4065 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4066</ul>
4067
4068<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4069
4070
4071<p>Some minimum performance criterias are critical to the user experience and
4072impacts the baseline assumptions developers would have when developing an app.
4073Android Watch devices SHOULD and other type of device implementations MUST meet
4074the following criteria:</p>
4075
4076<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4077
4078
4079<p>Device implementations MUST provide a smooth user interface by ensuring a
4080consistent frame rate and response times for applications and games. Device
4081implementations MUST meet the following requirements: </p>
4082
4083<ul>
4084 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4085often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4086 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4087list of 10K list entries as defined by the Android Compatibility Test Suite
4088(CTS) in less than 36 secs.</li>
4089 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4090application after it has been launched MUST take less than 1 second.</li>
4091</ul>
4092
4093<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4094
4095
4096<p>Device implementations MUST ensure internal storage file access performance consistency for read
4097and write operations. </p>
4098
4099<ul>
4100 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4101for a 256MB file using 10MB write buffer.</li>
4102 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4103256MB file using 4KB write buffer.</li>
4104 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4105a 256MB file using 10MB write buffer.</li>
4106 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4107256MB file using 4KB write buffer.</li>
4108</ul>
4109
4110<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4111
4112
4113<p>Device implementations MUST implement a security model consistent with the
4114Android platform security model as defined in Security and Permissions
4115reference 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
4116installation of self-signed applications without requiring any additional
4117permissions/certificates from any third parties/authorities. Specifically,
4118compatible devices MUST support the security mechanisms described in the follow
4119subsections.</p>
4120
4121<h2 id="9_1_permissions">9.1. Permissions</h2>
4122
4123
4124<p>Device implementations MUST support the Android permissions model as defined in
4125the 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
4126described in the SDK documentation; no permissions may be omitted, altered, or
4127ignored. Implementations MAY add additional permissions, provided the new
4128permission ID strings are not in the android.* namespace.</p>
4129
Svetoslav4bbf7402015-09-11 14:45:48 -0700[diff] [blame]4130<p>Permissions with a protection level of dangerous are runtime permissions. Applications
4131with targetSdkVersion > 22 request them at runtime. The system MUST show a dedicated UI for the
4132user to decide whether to grant the requested runtime permissions and also provide a UI for the
4133user to manage runtime permissions. On the system there MUST be one and only one
4134implementation of both the UI for the user to accept runtime permissions and the UI for
4135the user to manage runtime permissions.</p>
4136
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4137<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4138
4139
4140<p>Device implementations MUST support the Android application sandbox model, in
4141which each application runs as a unique Unixstyle UID and in a separate
4142process. Device implementations MUST support running multiple applications as
4143the same Linux user ID, provided that the applications are properly signed and
4144constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4145
4146<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4147
4148
4149<p>Device implementations MUST support the Android file access permissions model
4150as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4151
4152<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4153
4154
4155<p>Device implementations MAY include runtime environments that execute
4156applications using some other software or technology than the Dalvik Executable
4157Format or native code. However, such alternate execution environments MUST NOT
4158compromise the Android security model or the security of installed Android
4159applications, as described in this section.</p>
4160
4161<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4162standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4163
4164<p>Alternate runtimes MUST NOT be granted access to resources protected by
4165permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4166&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4167
4168<p>Alternate runtimes MUST NOT permit applications to make use of features
4169protected by Android permissions restricted to system applications.</p>
4170
4171<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4172alternate runtimes:</p>
4173
4174<ul>
4175 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4176Linux user IDs, etc.).</li>
4177 <li>MAY provide a single Android sandbox shared by all applications using the
4178alternate runtime.</li>
4179 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4180sandbox of any other app installed on the device, except through the standard
4181Android mechanisms of shared user ID and signing certificate.</li>
4182 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4183corresponding to other Android applications.</li>
4184 <li>MUST NOT be launched with, be granted, or grant to other applications any
4185privileges of the superuser (root), or of any other user ID.</li>
4186</ul>
4187
4188<p>The .apk files of alternate runtimes MAY be included in the system image of a
4189device implementation, but MUST be signed with a key distinct from the key used
4190to sign other applications included with the device implementation.</p>
4191
4192<p>When installing applications, alternate runtimes MUST obtain user consent for
4193the Android permissions used by the application. If an application needs to
4194make use of a device resource for which there is a corresponding Android
4195permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4196user that the application will be able to access that resource. If the runtime
4197environment does not record application capabilities in this manner, the
4198runtime environment MUST list all permissions held by the runtime itself when
4199installing any application using that runtime.</p>
4200
4201<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4202
4203<div class="note">
4204<p>This feature is optional for all device types.</p>
4205</div>
4206
4207
4208<p>Android includes support for multiple users and provides support for full user
4209isolation [<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
4210the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4211
4212<ul>
4213 <li>Device implementations that do not declare the android.hardware.telephony
4214feature flag MUST support restricted profiles, a feature that allows device
4215owners to manage additional users and their capabilities on the device. With
4216restricted profiles, device owners can quickly set up separate environments for
4217additional users to work in, with the ability to manage finer-grained
4218restrictions in the apps that are available in those environments.</li>
4219 <li>Conversely device implementations that declare the android.hardware.telephony
4220feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4221implementation of controls to enable /disable other users from accessing the
4222voice calls and SMS.</li>
4223 <li>Device implementations MUST, for each user, implement a security model
4224consistent with the Android platform security model as defined in Security and
4225Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4226 <li>Device implementations MAY support creating users and managed profiles via the
4227android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4228platform feature flag android.software.managed_users.
4229 <li>Device implementations that declare the feature flag
4230android.software.managed_users MUST use the upstream AOSP icon badge to
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4231represent the managed applications and other badge UI elements like Recents &amp;
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4232Notifications.</li>
4233 <li>Each user instance on an Android device MUST have separate and isolated
4234external storage directories. Device implementations MAY store multiple users'
4235data on the same volume or filesystem. However, the device implementation MUST
4236ensure that applications owned by and running on behalf a given user cannot
4237list, read, or write to data owned by any other user. Note that removable
4238media, such as SD card slots, can allow one user to access another&rsquo;s data by
4239means of a host PC. For this reason, device implementations that use removable
4240media for the external storage APIs MUST encrypt the contents of the SD card if
4241multiuser is enabled using a key stored only on non-removable media accessible
4242only to the system. As this will make the media unreadable by a host PC, device
4243implementations will be required to switch to MTP or a similar system to
4244provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4245implementations MAY but SHOULD NOT enable multi-user if they use removable
4246media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4247</ul>
4248
4249<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4250
4251
4252<p>Android includes support for warning users of any outgoing premium SMS message
4253[<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
4254carrier that may incur a charge to the user. Device implementations that
4255declare support for android.hardware.telephony MUST warn users before sending a
4256SMS message to numbers identified by regular expressions defined in
4257/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4258Project provides an implementation that satisfies this requirement.</p>
4259
4260<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4261
4262
4263<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4264(SELinux) mandatory access control (MAC) system and other security features in
4265the Linux kernel. SELinux or any other security features, if implemented below
4266the Android framework:</p>
4267
4268<ul>
4269 <li>MUST maintain compatibility with existing applications.</li>
4270 <li>MUST NOT have a visible user interface when a security violation is detected
4271and successfully blocked, but MAY have a visible user interface when an
4272unblocked security violation occurs resulting in a successful exploit.</li>
4273 <li>SHOULD NOT be user or developer configurable.</li>
4274</ul>
4275
4276<p>If any API for configuration of policy is exposed to an application that can
4277affect another application (such as a Device Administration API), the API MUST
4278NOT allow configurations that break compatibility.</p>
4279
4280<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4281if using a kernel other than Linux and meet the following requirements, which
4282are satisfied by the reference implementation in the upstream Android Open
4283Source Project.</p>
4284
4285<p>Device implementations:</p>
4286
4287<ul>
4288 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4289per-domain basis, and MUST configure all domains in enforcing mode. No
4290permissive mode domains are allowed, including domains specific to a
4291device/vendor.</li>
4292 <li>SHOULD load policy from /sepolicy file on the device.</li>
4293 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4294sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4295the policy MUST compile with all neverallow present, for both AOSP SELinux
4296domains as well as device/vendor specific domains.</li>
4297 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4298system image update.</li>
4299</ul>
4300
4301<p>Device implementations SHOULD retain the default SELinux policy provided in the
4302upstream Android Open Source Project, until they have first audited their
4303additions to the SELinux policy. Device implementations MUST be compatible with
4304the upstream Android Open Source Project.</p>
4305
4306<h2 id="9_8_privacy">9.8. Privacy</h2>
4307
4308<p>If the device implements functionality in the system that captures the contents
4309displayed on the screen and/or records the audio stream played on the device,
4310it MUST continuously notify the user whenever this functionality is enabled and
4311actively capturing/recording.</p>
4312
4313<p>If a device implementation has a mechanism that routes network data traffic
4314through a proxy server or VPN gateway by default (for example, preloading a VPN
4315service with android.permission.CONTROL_VPN granted), the device implementation
4316MUST ask for the user's consent before enabling that mechanism.</p>
4317
4318<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4319
4320<div class="note">
4321<p>Optional for Android device implementations without a lock screen.</p>
4322</div>
4323
4324
4325<p>If the device implementation supports a lock screen with PIN (numeric) or
4326PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4327application private data (/data partition), as well
4328as the SD card partition if it is a permanent, non-removable part of the device
4329[<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
4330be enabled all the time after the user has completed the out-of-box experience.
4331While this requirement is stated as SHOULD for this version of the Android
4332platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4333Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4334for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4335be written to storage at any time without being encrypted. Other than when in
4336active use, the encryption key SHOULD be AES encrypted with the lockscreen
4337passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4338If the user has not specified a lockscreen passcode or has disabled use of the
4339passcode for encryption, the system SHOULD use a default passcode to wrap the
4340encryption key. If the device provides a hardware-backed keystore, the password
4341stretching algorithm MUST be cryptographically bound to that keystore. The
4342encryption key MUST NOT be sent off the device (even when wrapped with the user
4343passcode and/or hardware bound key). The upstream Android Open Source project
4344provides a preferred implementation of this feature based on the linux kernel
4345feature dm-crypt.</p>
4346
4347<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4348
4349<p>
4350Verified boot is a feature that guarantees the integrity of the device software.
4351If a device implementation supports the feature, it MUST:
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4352</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4353<ul>
4354<li>Declare the platform feature flag android.software.verified_boot</li>
4355<li>Perform verification on every boot sequence</li>
4356<li>Start verification from a hardware key that is the root of trust, and go
4357all the way up to the system partition</li>
4358<li>Implement each stage of verification to check the integrity and authenticity
4359of all the bytes in the next stage before executing the code in the next stage</li>
4360<li>Use verification algorithms as strong as current recommendations
4361from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4362</ul>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4363
4364<p>Device implementations SHOULD support verified boot for device integrity.
4365While this requirement is SHOULD for this version of the Android platform,
4366it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4367in future versions of Android. The upstream Android Open Source Project provides
4368a preferred implementation of this feature based on the linux kernel feature dm-verity.
4369</p>
4370
4371<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4372
4373
4374<p>Device implementations MUST pass all tests described in this section.</p>
4375
4376<p>However, note that no software test package is fully comprehensive. For this
4377reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4378preferred implementation of Android available from the Android Open Source
4379Project. This will minimize the risk of introducing bugs that create
4380incompatibilities requiring rework and potential device updates.</p>
4381
4382<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4383
4384
4385<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
4386software on the device. Additionally, device implementers SHOULD use the
4387reference implementation in the Android Open Source tree as much as possible,
4388and MUST ensure compatibility in cases of ambiguity in CTS and for any
4389reimplementations of parts of the reference source code.</p>
4390
4391<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4392may itself contain bugs. The CTS will be versioned independently of this
4393Compatibility Definition, and multiple revisions of the CTS may be released for
4394Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4395at the time the device software is completed.</p>
4396
4397<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4398
4399
4400<p>Device implementations MUST correctly execute all applicable cases in the CTS
4401Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4402is intended to be run by a human operator to test functionality that cannot be
4403tested by an automated system, such as correct functioning of a camera and
4404sensors.</p>
4405
4406<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4407that is optional. Device implementations MUST pass all tests for hardware that
4408they possess; for instance, if a device possesses an accelerometer, it MUST
4409correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4410for features noted as optional by this Compatibility Definition Document MAY be
4411skipped or omitted.</p>
4412
4413<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4414above. However, since many builds are very similar, device implementers are not
4415expected to explicitly run the CTS Verifier on builds that differ only in
4416trivial ways. Specifically, device implementations that differ from an
4417implementation that has passed the CTS Verifier only by the set of included
4418locales, branding, etc. MAY omit the CTS Verifier test.</p>
4419
4420<h1 id="11_updatable_software">11. Updatable Software</h1>
4421
4422
4423<p>Device implementations MUST include a mechanism to replace the entirety of the
4424system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4425device restart MAY be required.</p>
4426
4427<p>Any method can be used, provided that it can replace the entirety of the
4428software preinstalled on the device. For instance, any of the following
4429approaches will satisfy this requirement:</p>
4430
4431<ul>
4432 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4433 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4434 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4435</ul>
4436
4437<p>However, if the device implementation includes support for an unmetered data
4438connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4439
4440<ul>
4441<li>Android Automotive implementations SHOULD support OTA downloads with offline
4442update via reboot.</li>
4443<li>All other device implementations MUST support OTA downloads with offline
4444update via reboot.</li>
4445</ul>
4446
4447<p>The update mechanism used MUST support updates without wiping user data. That
4448is, the update mechanism MUST preserve application private data and application
4449shared data. Note that the upstream Android software includes an update
4450mechanism that satisfies this requirement.</p>
4451
4452<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4453update mechanism SHOULD support verifying that the system image is binary
4454identical to expected result following an OTA. The block-based OTA
4455implementation in the upstream Android Open Source Project, added since Android
44565.1, satisfies this requirement.</p>
4457
4458<p>If an error is found in a device implementation after it has been released but
4459within its reasonable product lifetime that is determined in consultation with
4460the Android Compatibility Team to affect the compatibility of third-party
4461applications, the device implementer MUST correct the error via a software
4462update available that can be applied per the mechanism just described.</p>
4463
4464<h1 id="12_document_changelog">12. Document Changelog</h1>
4465
4466
4467<p>The following table contains a summary of the changes to the Compatibility
4468Definition in this release. </p>
4469<table>
4470 <tr>
4471 <th>Section</th>
4472 <th>Summary of change</th>
4473 </tr>
4474 <tr>
4475 <td>2. Device Types</td>
4476 <td>Added definition for Android automotive implementation.</td>
4477 </tr>
4478 <tr>
4479 <td>2.1 Device Configurations</td>
4480 <td>Added column for Android automotive implementation.</td>
4481 </tr>
4482 <tr>
4483 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4484 <td>New section added.</td>
4485 </tr>
4486 <tr>
4487 <td>3.4.1. WebView Compatibility</td>
4488 <td>Updated webview user agent string requirement to accomodate upstream
4489 implementation change.</td>
4490 </tr>
4491 <tr>
4492 <td>3.4.2. Browser compatibility</td>
4493 <td>Added Android automotive implementations as another case that MAY omit a
4494 browser application.</td>
4495 </tr>
4496 <tr>
4497 <td>3.7. Runtime Compatibility</td>
4498 <td>Updated required runtime heap size for smaller screens and added requirement
4499 for the new dpi bucket (280dpi).</td>
4500 </tr>
4501 <tr>
4502 <td>3.8.3. Notifications</td>
4503 <td>Clarified notification requirement for Android Watch, Television and
4504 Automotive implementations.</td>
4505 </tr>
4506 <tr>
4507 <td>3.8.10. Lock Screen Media Control<</td>
4508 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4509 </tr>
4510 <tr>
4511 <td>3.8.13. Unicode and font</td>
4512 <td>Relaxed Emoji character input method requirement.</td>
4513 </tr>
4514 <tr>
4515 <td>3.9. Device Administration</td>
4516 <td>Clarified condition when the full range of device administration policies
4517 has to be supported.</td>
4518 </tr>
4519 <tr>
4520 <td>3.10. Accessibility</td>
4521 <td>Added Android automotive requirements.</td>
4522 </tr>
4523 <tr>
4524 <td>3.11. Text-To-Speech</td>
4525 <td>Added Android automotive requirements.</td>
4526 </tr>
4527 <tr>
4528 <td>5.1. Media Codecs</td>
4529 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4530 </tr>
4531 <tr>
4532 <td>5.1.3 Video Codecs</td>
4533 <td>Added Android automotive requirements.</td>
4534 </tr>
4535 <tr>
4536 <td>7.1.1.3. Screen Density</td>
4537 <td>Added a new screen dpi (280dpi).</td>
4538 </tr>
4539 <tr>
4540 <td>7.1.5. Legacy Application Compatibility Mode</td>
4541 <td>Added Android automotive requirements.</td>
4542 </tr>
4543 <tr>
4544 <td>7.2 Input Devices</td>
4545 <td>Added general introduction statement.</td>
4546 </tr>
4547 <tr>
4548 <td>7.2.1. Keyboard</td>
4549 <td>Added Android Automotive requirements.</td>
4550 </tr>
4551 <tr>
4552 <td>7.2.3. Navigation Keys</td>
4553 <td>Added Android Automotive requirements.</td>
4554 </tr>
4555 <tr>
4556 <td>7.3.1. Accelerometer</td>
4557 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4558 </tr>
4559 <tr>
4560 <td>7.3.4. Gyroscope</td>
4561 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4562 </tr>
4563 <tr>
4564 <td>7.4.3 Bluetooth</td>
4565 <td>Added Android Automotive requirements.</td>
4566 </tr>
4567 <tr>
4568 <td>7.4.4. Near-Field Communications</td>
4569 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4570 </tr>
4571 <tr>
4572 <td>7.6.1. Minimum Memory and Storage</td>
4573 <td>Updated minimum memory requirements for lower resulution screen devices
4574 and added hard-limit requirement isLowRamDevice().</td>
4575 </tr>
4576 <tr>
4577 <td>7.6.2. Application Shared Storage</td>
4578 <td>Updated requirements when support for host machine access is mandatory.</td>
4579 </tr>
4580 <tr>
4581 <td>7.8.1. Microphone</td>
4582 <td>Added Android Automotive requirements.</td>
4583 </tr>
4584 <tr>
4585 <td>8.2. File I/O Access Performance</td>
4586 <td>Clarified requirements.</td>
4587 </tr>
4588 <tr>
4589 <td>9.8. Privacy</td>
4590 <td>Added privacy requirement for preloaded VPNs.</td>
4591 </tr>
4592 <tr>
4593 <td>9.9. Full-Disk Encryption</td>
4594 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4595 </tr>
4596 <tr>
4597 <td>9.10. Verified Boot</td>
4598 <td>Clarified definition of verified boot.</td>
4599 </tr>
4600 <tr>
4601 <td>11. Updatable Software</td>
4602 <td>Clarified the OTA download requirement is allowed but not mandatory for
4603 Android Automotive implementations.</td>
4604 </tr>
4605</table>
4606
4607
4608<h1 id="13_contact_us">13. Contact Us</h1>
4609
4610
4611<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
4612does not cover.</p>
4613
4614<h1 id="14_resources">14. Resources</h1>
4615
4616
4617<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4618
4619<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4620
4621<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>
4622
4623<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>
4624
4625<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4626
4627<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>
4628
4629<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>
4630
4631<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>
4632
4633<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>
4634
4635<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>
4636
4637<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>
4638
4639<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>
4640
4641<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4642
4643<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4644
4645<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>
4646
4647<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>
4648
4649<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4650
4651<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4652
4653<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4654
4655<p>20. Dalvik Executable Format and bytecode specification: available in the
4656Android source code, at dalvik/docs</p>
4657
4658<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>
4659
4660<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>
4661
4662<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>
4663
4664<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>
4665
4666<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4667
4668<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>
4669
4670<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>
4671
4672<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>
4673
4674<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>
4675
4676<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>
4677
4678<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>
4679
4680<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>
4681
4682<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>
4683
4684<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>
4685
4686<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>
4687
4688<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>
4689
4690<p>37. Settings.Secure LOCATION_MODE:</p>
4691
4692<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>
4693
4694<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>
4695
4696<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>
4697
4698<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>
4699
4700<p>41. Android Device Owner App:</p>
4701
4702<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>
4703
4704<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>
4705
4706<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>
4707
4708<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4709
4710<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>
4711
4712<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>
4713
4714<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>
4715
4716<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>
4717
4718<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>
4719
4720<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>
4721
4722<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>
4723
4724<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>
4725
4726<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4727
4728<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>
4729
4730<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>
4731
4732<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4733
4734<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4735
4736<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4737
4738<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>
4739
4740<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4741
4742<p>60. Android Application Development-Related Settings:</p>
4743
4744<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>
4745
4746<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>
4747
4748<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>
4749
4750<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4751
4752<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>
4753
4754<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>
4755
4756<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4757
4758<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>
4759
4760<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>
4761
4762<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>
4763
4764<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>
4765
4766<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>
4767
4768<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>
4769
4770<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>
4771
4772<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4773
4774<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>
4775
4776<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>
4777
4778<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>
4779
4780<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>
4781
4782<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>
4783
4784<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>
4785
4786<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>
4787
4788<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>
4789
4790<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>
4791
4792<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>
4793
4794<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>
4795
4796<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>
4797
4798<p>86. Android NFC Sharing Settings:</p>
4799
4800<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>
4801
4802<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>
4803
4804<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>
4805
4806<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>
4807
4808<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>
4809
4810<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>
4811
4812<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>
4813
4814<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>
4815
4816<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>
4817
4818<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>
4819
4820<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4821
4822<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>
4823
4824<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>
4825
4826<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>
4827
4828<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>
4829
4830<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>
4831
4832<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>
4833
4834<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>
4835
4836<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4837
4838<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>
4839
4840<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4841
4842<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>
4843
4844<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4845
4846<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>
4847
4848<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4849
4850<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>
4851
4852<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>
4853
4854<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>
4855
4856<p>Many of these resources are derived directly or indirectly from the Android
4857SDK, and will be functionally identical to the information in that SDK&rsquo;s
4858documentation. In any cases where this Compatibility Definition or the
4859Compatibility Test Suite disagrees with the SDK documentation, the SDK
4860documentation is considered authoritative. Any technical details provided in
4861the references included above are considered by inclusion to be part of this
4862Compatibility Definition.</p>
4863
4864</div>
4865</body>
4866</html>