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2<head>
3<title>Android ANDROID_VERSION Compatibility Definition</title>
Clay Murphyb6581772015-08-26 11:11:06 -0700[diff] [blame]4<link rel="stylesheet" type="text/css" href="source/android-cdd.css"/>
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>
Owain Davies4f8796e2015-09-24 14:01:26 +0100[diff] [blame^]713 <td>A hardware serial number, which MUST be available and unique across
714devices with the same MODEL and MANUFACTURER. The value of this field MUST
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]715be encodable as 7-bit ASCII and match the regular expression &ldquo;^([a-zA-Z0-9]{6,20})$&rdquo;.</td>
716 </tr>
717 <tr>
718 <td>TAGS</td>
719 <td>A comma-separated list of tags chosen by the device implementer that further
720distinguishes the build. This field MUST have one of the values corresponding
721to the three typical Android platform signing configurations: release-keys,
722dev-keys, test-keys. </td>
723 </tr>
724 <tr>
725 <td>TIME</td>
726 <td>A value representing the timestamp of when the build occurred.</td>
727 </tr>
728 <tr>
729 <td>TYPE</td>
730 <td>A value chosen by the device implementer specifying the runtime configuration
731of the build. This field MUST have one of the values corresponding to the three
732typical Android runtime configurations: user, userdebug, or eng.</td>
733 </tr>
734 <tr>
735 <td>USER</td>
736 <td>A name or user ID of the user (or automated user) that generated the build.
737There are no requirements on the specific format of this field, except that it
738MUST NOT be null or the empty string ("").</td>
739 </tr>
740</table>
741
742
743<h3 id="3_2_3_intent_compatibility">3.2.3. Intent Compatibility</h3>
744
745
746<p>Device implementations MUST honor Android&rsquo;s loose-coupling intent system, as
747described in the sections below. By&ldquo;honored &rdquo; it is meant that the device
748implementer MUST provide an Android Activity or Service that specifies a
749matching intent filter that binds to and implements correct behavior for each
750specified intent pattern.</p>
751
752<h4 id="3_2_3_1_core_application_intents">3.2.3.1. Core Application Intents</h4>
753
754
755<p>Android intents allow application components to request functionality from
756other Android components. The Android upstream project includes a list of
757applications considered core Android applications, which implements several
758intent patterns to perform common actions. The core Android applications are:</p>
759
760<ul>
761 <li>Desk Clock</li>
762 <li>Browser</li>
763 <li>Calendar</li>
764 <li>Contacts</li>
765 <li>Gallery</li>
766 <li>GlobalSearch</li>
767 <li>Launcher</li>
768 <li>Music</li>
769 <li>Settings</li>
770</ul>
771
772<p>Device implementations SHOULD include the core Android applications as
773appropriate but MUST include a component implementing the same intent patterns
774defined by all the &ldquo;public&rdquo; Activity or Service components of these core
775Android applications. Note that Activity or Service components are considered
776&ldquo;public&rdquo; when the attribute android:exported is absent or has the value true.</p>
777
778<h4 id="3_2_3_2_intent_overrides">3.2.3.2. Intent Overrides</h4>
779
780
781<p>As Android is an extensible platform, device implementations MUST allow each
782intent 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
783implementation allows this by default; device implementers MUST NOT attach
784special privileges to system applications' use of these intent patterns, or
785prevent third-party applications from binding to and assuming control of these
786patterns. This prohibition specifically includes but is not limited to
787disabling the&ldquo;Chooser&rdquo; user interface that allows the user to select between
788multiple applications that all handle the same intent pattern.</p>
789
790<p>However, device implementations MAY provide default activities for specific URI
791patterns (eg. http://play.google.com) if the default activity provides a more
792specific filter for the data URI. For example, an intent filter specifying the
793data 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
794modify the default activity for intents.</p>
795
796<h4 id="3_2_3_3_intent_namespaces">3.2.3.3. Intent Namespaces</h4>
797
798
799<p>Device implementations MUST NOT include any Android component that honors any
800new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
801string in the android.* or com.android.* namespace. Device implementers MUST
802NOT include any Android components that honor any new intent or broadcast
803intent patterns using an ACTION, CATEGORY, or other key string in a package
804space belonging to another organization. Device implementers MUST NOT alter or
805extend 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
806and obviously associated with their own organization. This prohibition is
807analogous to that specified for Java language classes in <a href="#3_6_api_namespaces">section 3.6</a>.</p>
808
809<h4 id="3_2_3_4_broadcast_intents">3.2.3.4. Broadcast Intents</h4>
810
811
812<p>Third-party applications rely on the platform to broadcast certain intents to
813notify them of changes in the hardware or software environment.
814Android-compatible devices MUST broadcast the public broadcast intents in
815response to appropriate system events. Broadcast intents are described in the
816SDK documentation.</p>
817
818<h4 id="3_2_3_5_default_app_settings">3.2.3.5. Default App Settings</h4>
819
820
821<p>Android includes settings that provide users an easy way to select their
822default applications, for example for Home screen or SMS. Where it makes sense,
823device implementations MUST provide a similar settings menu and be compatible
824with the intent filter pattern and API methods described in the SDK
825documentation as below.</p>
826
827<p>Device implementations:</p>
828
829<ul>
830 <li>MUST honor the android.settings.HOME_SETTINGS intent to show a default app
831settings menu for Home Screen, if the device implementation reports
832android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
833 <li>MUST provide a settings menu that will call the
834android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
835change the default SMS application, if the device implementation reports
836android.hardware.telephony [<a href="http://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]</li>
837 <li>MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
838app settings menu for Tap and Pay, if the device implementation reports
839android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a></li>
840</ul>
841
842<h2 id="3_3_native_api_compatibility">3.3. Native API Compatibility</h2>
843
844
845<h3 id="3_3_1_application_binary_interfaces">3.3.1. Application Binary Interfaces</h3>
846
847
848<p>Managed Dalvik bytecode can call into native code provided in the application
849.apk file as an ELF .so file compiled for the appropriate device hardware
850architecture. As native code is highly dependent on the underlying processor
851technology, Android defines a number of Application Binary Interfaces (ABIs) in
852the Android NDK. Device implementations MUST be compatible with one or more
853defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
854
855<p>If a device implementation includes support for an Android ABI, it:</p>
856
857<ul>
858 <li>MUST include support for code running in the managed environment to call into
859native code, using the standard Java Native Interface (JNI) semantics</li>
860 <li>MUST be source-compatible (i.e. header compatible) and binary-compatible (for
861the ABI) with each required library in the list below</li>
862 <li>MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported</li>
863 <li>MUST accurately report the native Application Binary Interface (ABI) supported
864by the device, via the android.os.Build.SUPPORTED_ABIS,
865android.os.Build.SUPPORTED_32_BIT_ABIS, and
866android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
867of ABIs ordered from the most to the least preferred one</li>
868 <li>MUST report, via the above parameters, only those ABIs documented in the latest
869version of the Android NDK, &ldquo;NDK Programmer&rsquo;s Guide | ABI Management&rdquo; in docs/
870directory</li>
871 <li>SHOULD be built using the source code and header files available in the
872upstream Android Open Source Project</li>
873</ul>
874
875<p>The following native code APIs MUST be available to apps that include native
876code:</p>
877
878<ul>
879 <li>libc (C library)</li>
880 <li>libm (math library)</li>
881 <li>Minimal support for C++</li>
882 <li>JNI interface</li>
883 <li>liblog (Android logging)</li>
884 <li>libz (Zlib compression)</li>
885 <li>libdl (dynamic linker)</li>
886 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
887 <li>libGLESv2.so (OpenGL ES 2.0)</li>
888 <li>libGLESv3.so (OpenGL ES 3.x)</li>
889 <li>libEGL.so (native OpenGL surface management)</li>
890 <li>libjnigraphics.so</li>
891 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
892 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
893 <li>libandroid.so (native Android activity support)</li>
894 <li>libmediandk.so (native media APIs support)</li>
895 <li>Support for OpenGL, as described below</li>
896</ul>
897
898<p>Note that future releases of the Android NDK may introduce support for
899additional ABIs. If a device implementation is not compatible with an existing
900predefined ABI, it MUST NOT report support for any ABIs at all.</p>
901
902<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
903(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
904Android 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
905symbols must be present, only the corresponding functions for OpenGL ES
906versions and extensions actually supported by the device must be fully
907implemented.</p>
908
909<p>Native code compatibility is challenging. For this reason, device implementers
910are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
911Android Open Source Project. </p>
912
913<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9143.3.2. 32-bit ARM Native Code Compatibility
915</h3>
916
917<p>The ARMv8 architecture deprecates several CPU operations, including some
918operations used in existing native code. On 64-bit ARM devices, the following
919deprecated operations MUST remain available to 32-bit native ARM code, either
920through native CPU support or through software emulation:</p>
921
922<ul>
923<li>SWP and SWPB instructions</li>
924<li>SETEND instruction</li>
925<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
926</ul>
927
928<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
929from 32-bit ARM native code. For compatibility with applications built using this
930NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
931by 32-bit ARM applications:</p>
932
933<ul>
934<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
935supported by the device</li>
936<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
937highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
938</ul>
939
940<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
941applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
942non-ARM applications.</p>
943
944<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
945
946
947<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
948
949<div class="note">
950<p>Android Watch devices MAY, but all other device implementations MUST provide
951a complete implementation of the android.webkit.Webview API.</p>
952</div>
953
954
955<p>The platform feature android.software.webview MUST be reported on any device
956that provides a complete implementation of the android.webkit.WebView API, and
957MUST NOT be reported on devices without a complete implementation of the API.
958The Android Open Source implementation uses code from the Chromium Project to
959implement 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
960rendering system, device implementers MUST use the specific upstream build of
961Chromium in the WebView implementation. Specifically:</p>
962
963<ul>
964 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
965build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
966includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
967 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]968<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]969AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
970Safari/537.36</p>
971 <ul>
972 <li>The value of the $(VERSION) string MUST be the same as the value for
973android.os.Build.VERSION.RELEASE.</li>
974 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
975 note that this is a webview</li>
976 <li>The value of the $(MODEL) string MUST be the same as the value for
977android.os.Build.MODEL.</li>
978 <li>The value of the $(BUILD) string MUST be the same as the value for
979android.os.Build.ID.</li>
980 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
981upstream Android Open Source Project.</li>
982 <li>Device implementations MAY omit Mobile in the user agent string.</li>
983 </ul></li></ul>
984
985<p>The WebView component SHOULD include support for as many HTML5 features as
986possible and if it supports the feature SHOULD conform to the HTML5
987specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
988
989<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
990
991<div class="note">
992<p>Android Television, Watch, and Android Automotive implementations MAY omit a
993browser application, but MUST support the public intent patterns as described in
994<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
995of device implementations MUST include a standalone Browser application for
996general user web browsing.</p>
997</div>
998
999<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1000However, even if an alternate Browser application is used, the
1001android.webkit.WebView component provided to third-party applications MUST be
1002based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1003
1004<p>Implementations MAY ship a custom user agent string in the standalone Browser
1005application.</p>
1006
1007<p>The standalone Browser application (whether based on the upstream WebKit
1008Browser application or a third-party replacement) SHOULD include support for as
1009much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1010APIs associated with HTML5:</p>
1011
1012<ul>
1013 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1014 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1015 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1016</ul>
1017
1018<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1019[<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
1020IndexedDB over webstorage, IndexedDB is expected to become a required component
1021in a future version of Android.</p>
1022
1023<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1024
1025
1026<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1027consistent with the preferred implementation of the upstream Android Open
1028Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1029
1030<ul>
1031 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1032 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1033type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1034 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1035</ul>
1036
1037<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1038significant portions of the platform for behavioral compatibility, but not all.
1039It is the responsibility of the implementer to ensure behavioral compatibility
1040with the Android Open Source Project. For this reason, device implementers
1041SHOULD use the source code available via the Android Open Source Project where
1042possible, rather than re-implement significant parts of the system.</p>
1043
1044<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1045
1046
1047<p>Android follows the package and class namespace conventions defined by the Java
1048programming language. To ensure compatibility with third-party applications,
1049device implementers MUST NOT make any prohibited modifications (see below) to
1050these package namespaces:</p>
1051
1052<ul>
1053 <li>java.*</li>
1054 <li>javax.*</li>
1055 <li>sun.*</li>
1056 <li>android.*</li>
1057 <li>com.android.*</li>
1058</ul>
1059
1060<p><strong>Prohibited modifications include</strong>:</p>
1061
1062<ul>
1063 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1064platform by changing any method or class signatures, or by removing classes or
1065class fields.</li>
1066 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1067such modifications MUST NOT impact the stated behavior and Java-language
1068signature of any publicly exposed APIs.</li>
1069 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1070or interfaces, or fields or methods to existing classes or interfaces) to the
1071APIs above.</li>
1072</ul>
1073
1074<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,
1075device implementers MUST NOT expose new APIs or alter existing APIs in the
1076namespaces noted above. Device implementers MAY make internal-only
1077modifications, but those modifications MUST NOT be advertised or otherwise
1078exposed to developers.</p>
1079
1080<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1081namespace owned by or referring to another organization. For instance, device
1082implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1083Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1084namespaces. Additionally, if a device implementation includes custom APIs
1085outside the standard Android namespace, those APIs MUST be packaged in an
1086Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1087lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1088APIs.</p>
1089
1090<p>If a device implementer proposes to improve one of the package namespaces above
1091(such as by adding useful new functionality to an existing API, or adding a new
1092API), 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
1093information on that site.</p>
1094
1095<p>Note that the restrictions above correspond to standard conventions for naming
1096APIs in the Java programming language; this section simply aims to reinforce
1097those conventions and make them binding through inclusion in this Compatibility
1098Definition.</p>
1099
1100<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1101
1102
1103<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1104Dalvik 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
1105the Dalvik Executable Format, and the reference implementation&rsquo;s package
1106management system.</p>
1107
1108<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1109accordance with the upstream Android platform, and as specified by the
1110following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1111
1112<p>Note that memory values specified below are considered minimum values and
1113device implementations MAY allocate more memory per application.</p>
1114
1115<table>
1116 <tr>
1117 <th>Screen Layout</th>
1118 <th>Screen Density</th>
1119 <th>Minimum Application Memory</th>
1120 </tr>
1121 <tr>
1122 <td rowspan="10">small/normal</td>
1123 <td>120 dpi (ldpi)</td>
1124 <td rowspan="2">32MB</td>
1125 </tr>
1126 <tr>
1127 <td>160 dpi (mdpi)</td>
1128 </tr>
1129 <tr>
1130 <td>213 dpi (tvdpi)</td>
1131 <td rowspan="3">48MB</td>
1132 </tr>
1133 <tr>
1134 <td>240 dpi (hdpi)</td>
1135 </tr>
1136 <tr>
1137 <td>280 dpi (280dpi)</td>
1138 </tr>
1139 <tr>
1140 <td>320 dpi (xhdpi)</td>
1141 <td>80MB</td>
1142 </tr>
1143 <tr>
1144 <td>400 dpi (400dpi)</td>
1145 <td>96MB</td>
1146 </tr>
1147 <tr>
1148 <td>480 dpi (xxhdpi)</td>
1149 <td>128MB</td>
1150 </tr>
1151 <tr>
1152 <td>560 dpi (560dpi)</td>
1153 <td>192MB</td>
1154 </tr>
1155 <tr>
1156 <td>640 dpi (xxxhdpi)</td>
1157 <td>256MB</td>
1158 </tr>
1159 <tr>
1160 <td rowspan="10">large</td>
1161 <td>120 dpi (ldpi)</td>
1162 <td>32MB</td>
1163 </tr>
1164 <tr>
1165 <td>160 dpi (mdpi)</td>
1166 <td>48MB</td>
1167 </tr>
1168 <tr>
1169 <td>213 dpi (tvdpi)</td>
1170 <td rowspan="2">80MB</td>
1171 </tr>
1172 <tr>
1173 <td>240 dpi (hdpi)</td>
1174 </tr>
1175 <tr>
1176 <td>280 dpi (280dpi)</td>
1177 <td>96MB</td>
1178 </tr>
1179 <tr>
1180 <td>320 dpi (xhdpi)</td>
1181 <td>128MB</td>
1182 </tr>
1183 <tr>
1184 <td>400 dpi (400dpi)</td>
1185 <td>192MB</td>
1186 </tr>
1187 <tr>
1188 <td>480 dpi (xxhdpi)</td>
1189 <td>256MB</td>
1190 </tr>
1191 <tr>
1192 <td>560 dpi (560dpi)</td>
1193 <td>384MB</td>
1194 </tr>
1195 <tr>
1196 <td>640 dpi (xxxhdpi)</td>
1197 <td>512MB</td>
1198 </tr>
1199 <tr>
1200 <td rowspan="10">xlarge</td>
1201 <td>120 dpi (ldpi)</td>
1202 <td>48MB</td>
1203 </tr>
1204 <tr>
1205 <td>160 dpi (mdpi)</td>
1206 <td>80MB</td>
1207 </tr>
1208 <tr>
1209 <td>213 dpi (tvdpi)</td>
1210 <td rowspan="2">96MB</td>
1211 </tr>
1212 <tr>
1213 <td>240 dpi (hdpi)</td>
1214 </tr>
1215 <tr>
1216 <td>280 dpi (280dpi)</td>
1217 <td>144MB</td>
1218 </tr>
1219 <tr>
1220 <td>320 dpi (xhdpi)</td>
1221 <td>192MB</td>
1222 </tr>
1223 <tr>
1224 <td>400 dpi (400dpi)</td>
1225 <td>288MB</td>
1226 </tr>
1227 <tr>
1228 <td>480 dpi (xxhdpi)</td>
1229 <td>384MB</td>
1230 </tr>
1231 <tr>
1232 <td>560 dpi (560dpi)</td>
1233 <td>576MB</td>
1234 </tr>
1235 <tr>
1236 <td>640 dpi (xxxhdpi)</td>
1237 <td>768MB</td>
1238 </tr>
1239</table>
1240
1241
1242<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1243
1244
1245<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1246
1247
1248<p>Android includes a launcher application (home screen) and support for
1249third-party applications to replace the device launcher (home screen). Device
1250implementations that allow third-party applications to replace the device home
1251screen MUST declare the platform feature android.software.home_screen.</p>
1252
1253<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1254
1255<div class="note">
1256<p>Widgets are optional for all Android device implementations, but SHOULD be
1257supported on Android Handheld devices.</p>
1258</div>
1259
1260
1261<p>Android defines a component type and corresponding API and lifecycle that
1262allows 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
1263implementations. Device implementations that support embedding widgets on the
1264home screen MUST meet the following requirements and declare support for
1265platform feature android.software.app_widgets.</p>
1266
1267<ul>
1268 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1269interface affordances to add, configure, view, and remove AppWidgets directly
1270within the Launcher.</li>
1271 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1272the standard grid size. See the App Widget Design Guidelines in the Android SDK
1273documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1274 <li>Device implementations that include support for lock screen MAY support
1275application widgets on the lock screen.</li>
1276</ul>
1277
1278<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1279
1280
1281<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>
1282
1283<p>Some APIs allow applications to perform notifications or attract attention
1284using hardware&#8212;specifically sound, vibration, and light. Device implementations
1285MUST support notifications that use hardware features, as described in the SDK
1286documentation, and to the extent possible with the device implementation
1287hardware. For instance, if a device implementation includes a vibrator, it MUST
1288correctly implement the vibration APIs. If a device implementation lacks
1289hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1290is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1291
1292<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1293etc.) provided for in the APIs
1294[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1295or in the Status/System Bar icon style guide
1296[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1297which in the case of an Android Television device includes the possibility to not display the
1298notifications. Device implementers MAY provide an alternative user experience for
1299notifications than that provided by the reference Android Open Source
1300implementation; however, such alternative notification systems MUST support
1301existing notification resources, as above. </p>
1302
1303<p>Android includes support for various notifications, such as:</p>
1304
1305<ul>
1306 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1307 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1308 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1309</ul>
1310
1311<p>Android device implementations, when such notifications are made visible, MUST properly execute
1312Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1313APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1314</p>
1315
1316<p>Android includes Notification Listener Service APIs that allow apps (once
1317explicitly enabled by the user) to receive a copy of all notifications as they
1318are posted or updated. Device implementations MUST correctly and promptly send
1319notifications in their entirety to all such installed and user-enabled listener
1320services, including any and all metadata attached to the Notification object.</p>
1321
1322<h3 id="3_8_4_search">3.8.4. Search</h3>
1323
1324
1325<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
1326expose their application&rsquo;s data into the global system search. Generally
1327speaking, this functionality consists of a single, system-wide user interface
1328that allows users to enter queries, displays suggestions as users type, and
1329displays results. The Android APIs allow developers to reuse this interface to
1330provide search within their own apps, and allow developers to supply results to
1331the common global search user interface.</p>
1332
1333<p>Android device implementations SHOULD include global search, a single, shared,
1334system-wide search user interface capable of real-time suggestions in response
1335to user input. Device implementations SHOULD implement the APIs that allow
1336developers to reuse this user interface to provide search within their own
1337applications. Device implementations that implement the global search interface
1338MUST implement the APIs that allow third-party applications to add suggestions
1339to the search box when it is run in global search mode. If no third-party
1340applications are installed that make use of this functionality, the default
1341behavior SHOULD be to display web search engine results and suggestions.</p>
1342
1343<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1344
1345
1346<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1347end 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
1348some high-visibility manner.</p>
1349
1350<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1351
1352
1353<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1354across an entire Activity or application.</p>
1355
1356<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1357application developers to use if they want to match the Holo theme look and
1358feel 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
1359exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1360
1361<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1362application developers to use if they want to match the design theme&rsquo;s look and
1363feel across the wide variety of different Android device types. Device
1364implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1365of 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>
1366
1367<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1368styles for application developers to use if they want to match the look and
1369feel of the device theme as defined by the device implementer. Device
1370implementations MAY modify the Device Default theme attributes exposed to
1371applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1372
1373<p>Android supports a new variant theme with translucent system bars, which allows
1374application developers to fill the area behind the status and navigation bar
1375with their app content. To enable a consistent developer experience in this
1376configuration, it is important the status bar icon style is maintained across
1377different device implementations. Therefore, Android device implementations
1378MUST use white for system status icons (such as signal strength and battery
1379level) and notifications issued by the system, unless the icon is indicating a
1380problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1381
1382<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1383
1384
1385<p>Android defines a component type and corresponding API and lifecycle that
1386allows 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
1387input capabilities that display as a wallpaper, behind other applications.</p>
1388
1389<p>Hardware is considered capable of reliably running live wallpapers if it can
1390run all live wallpapers, with no limitations on functionality, at a reasonable
1391frame rate with no adverse effects on other applications. If limitations in the
1392hardware cause wallpapers and/or applications to crash, malfunction, consume
1393excessive CPU or battery power, or run at unacceptably low frame rates, the
1394hardware is considered incapable of running live wallpaper. As an example, some
1395live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1396Live wallpaper will not run reliably on hardware that does not support multiple
1397OpenGL contexts because the live wallpaper use of an OpenGL context may
1398conflict with other applications that also use an OpenGL context.</p>
1399
1400<p>Device implementations capable of running live wallpapers reliably as described
1401above SHOULD implement live wallpapers, and when implemented MUST report the
1402platform feature flag android.software.live_wallpaper.</p>
1403
1404<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1405
1406<div class="note">
1407<p>As the Recent function navigation key is OPTIONAL, the requirements to
1408implement the overview screen is OPTIONAL for Android Television devices and
1409Android Watch devices.</p>
1410</div>
1411
1412
1413<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
1414accessed activities and tasks using a thumbnail image of the application&rsquo;s
1415graphical state at the moment the user last left the application. Device
1416implementations 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>
1417
1418<ul>
1419 <li>MUST display affiliated recents as a group that moves together.</li>
1420 <li>MUST support at least up to 20 displayed activities.</li>
1421 <li>MUST at least display the title of 4 activities at a time.</li>
1422 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1423 <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>
1424 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1425interacts with screens.</li>
1426</ul>
1427
1428<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1429interface (or a similar thumbnail-based interface) for the overview screen.</p>
1430
1431<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1432
1433
1434<p>Android includes support for Input Management and support for third-party input
1435method 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
1436the device MUST declare the platform feature android.software.input_methods and
1437support IME APIs as defined in the Android SDK documentation.</p>
1438
1439<p>Device implementations that declare the android.software.input_methods feature
1440MUST provide a user-accessible mechanism to add and configure third-party input
1441methods. Device implementations MUST display the settings interface in response
1442to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1443
1444<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1445
1446
1447<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1448Media Notification Template that allows media applications to integrate with
1449playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1450Device implementations that support a lock screen, unless an Android Automotive or Watch
1451implementation, MUST display the Lockscreen Notifications including the Media Notification
1452Template.</p>
1453
1454<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1455
1456
1457<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
1458a power source is idle or docked in a desk dock. Android Watch devices MAY
1459implement Dreams, but other types of device implementations SHOULD include
1460support for Dreams and provide a settings option for users to configure Dreams
1461in response to the android.settings.DREAM_SETTINGS intent.</p>
1462
1463<h3 id="3_8_12_location">3.8.12. Location</h3>
1464
1465
1466<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1467location coordinates, location modes MUST be displayed in the Location menu
1468within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1469
1470<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1471
1472
1473<p>Android includes support for color emoji characters. When Android device
1474implementations include an IME, devices SHOULD provide an input method to the
1475user 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>
1476
1477<p>Android includes support for Roboto 2 font with different
1478weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1479sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1480the languages available on the device and full Unicode 7.0 coverage of Latin,
1481Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1482all glyphs in the currency symbols block of Unicode 7.0.</p>
1483
1484<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1485
1486
1487<p>Android includes features that allow security-aware applications to perform
1488device administration functions at the system level, such as enforcing password
1489policies or performing remote wipe, through the Android Device Administration
1490API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1491Device implementations MUST provide an implementation of the DevicePolicyManager class
1492[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1493Device implementations that include support for PIN (numeric) or PASSWORD
1494(alphanumeric) based lock screens MUST support the full range of device
1495administration policies defined in the Android SDK documentation
1496[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1497and report the platform feature android.software.device_admin.</p>
1498
1499<p>Device implementations MAY have a preinstalled application performing device
1500administration functions but this application MUST NOT be set out-of-the box as
1501the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1502
1503<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1504
1505
1506<p>Android provides an accessibility layer that helps users with disabilities to
1507navigate their devices more easily. In addition, Android provides platform APIs
1508that enable accessibility service implementations to receive callbacks for user
1509and system events and generate alternate feedback mechanisms, such as
1510text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1511
1512<p>Device implementations include the following requirements:</p>
1513
1514<ul>
1515<li>Android Automotive implementations SHOULD provide an implementation of the
1516Android accessibility framework consistent with the default Android
1517implementation.</li>
1518<li>Device implementations (Android Automotive excluded) MUST provide an
1519implementation of the Android accessibility framework consistent with the
1520default Android implementation.</li>
1521<li>Device implementations (Android Automotive excluded) MUST support
1522third-party accessibility service implementations through the
1523android.accessibilityservice APIs
1524[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1525<li>Device implementations (Android Automotive excluded) MUST generate
1526AccessibilityEvents and deliver these events to all registered
1527AccessibilityService implementations in a manner consistent with the default
1528Android implementation</li>
1529<li> Device implementations (Android Automotive and Android Watch devices with
1530no audio output excluded), MUST provide a user-accessible mechanism to enable
1531and disable accessibility services, and MUST display this interface in response
1532to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1533</ul>
1534
1535<p>Additionally, device implementations SHOULD provide an implementation of an
1536accessibility service on the device, and SHOULD provide a mechanism for users
1537to enable the accessibility service during device setup. An open source
1538implementation of an accessibility service is available from the Eyes Free
1539project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1540
1541<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1542
1543
1544<p>Android includes APIs that allow applications to make use of text-to-speech
1545(TTS) services and allows service providers to provide implementations of TTS
1546services [<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
1547MUST meet these requirements related to the Android TTS framework. </p>
1548
1549<p>Android Automotive implementations:</p>
1550<ul>
1551<li>MUST support the Android TTS framework APIs.</li>
1552<li>MAY support installation of third-party TTS engines. If supported, partners
1553MUST provide a user-accessible interface that allows the user to select a TTS
1554engine for use at system level.</li>
1555</ul>
1556
1557<p>All other device implementations:</p>
1558
1559<ul>
1560 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1561supporting the languages available on the device. Note that the upstream
1562Android open source software includes a full-featured TTS engine
1563implementation.
1564 <li> MUST support installation of third-party TTS engines
1565 <li> MUST provide a user-accessible interface that allows users to select a TTS
1566engine for use at the system level
1567</ul>
1568
1569<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1570
1571
1572<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1573content to Android Television devices. TIF provides a standard API to create
1574input modules that control Android Television devices. Android Television
1575device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1576
1577<p>Device implementations that support TIF MUST declare the platform feature
1578android.software.live_tv.</p>
1579
1580<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1581
1582
1583<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1584by 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>
1585
1586<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
1587files from installing and running correctly on other compatible devices.</p>
1588
1589<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1590
1591
1592<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1593
1594
1595<p>Device implementations MUST support the core media formats specified in the
1596Android 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
1597implementations MUST support the media formats, encoders, decoders, file types,
1598and container formats defined in the tables below and reported via MediaCodecList
1599[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1600Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1601[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1602113</a>].
1603
1604All of these codecs are
1605provided as software implementations in the preferred Android implementation
1606from the Android Open Source Project.</p>
1607
1608<p>Please note that neither Google nor the Open Handset Alliance make any
1609representation that these codecs are free from third-party patents. Those
1610intending to use this source code in hardware or software products are advised
1611that implementations of this code, including in open source software or
1612shareware, may require patent licenses from the relevant patent holders.</p>
1613
1614<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1615
1616<table>
1617 <tr>
1618 <th>Format/Codec</th>
1619 <th>Encoder</th>
1620 <th>Decoder</th>
1621 <th>Details</th>
1622 <th>Supported File Types/Container Formats</th>
1623 </tr>
1624 <tr>
1625 <td>MPEG-4 AAC Profile</p>
1626
1627<p>(AAC LC)</td>
1628 <td>REQUIRED<sup>1</sup></td>
1629 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1630 <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]163148 kHz.</td>
1632 <td>
1633 <ul>
1634 <li class="table_list">3GPP (.3gp)</li>
1635 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1636 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1637supported)</li>
1638 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1639 </tr>
1640 <tr>
1641 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1642 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1643 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1644 <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]1645to 48 kHz.</td>
1646 <td></td>
1647 </tr>
1648 <tr>
1649 <td>MPEG-4 HE AACv2</p>
1650
1651<p>Profile (enhanced AAC+)</td>
1652 <td> </td>
1653 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1654 <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]1655to 48 kHz.</td>
1656 <td></td>
1657 </tr>
1658 <tr>
1659 <td>AAC ELD (enhanced low delay AAC)</td>
1660 <td>REQUIRED<sup>1</sup> </p>
1661
1662<p>(Android 4.1+)</td>
1663 <td>REQUIRED</p>
1664
1665<p>(Android 4.1+)</td>
1666 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1667 <td></td>
1668 </tr>
1669 <tr>
1670 <td>AMR-NB</td>
1671 <td>REQUIRED<sup>3</sup></td>
1672 <td>REQUIRED<sup>3</sup></td>
1673 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1674 <td>3GPP (.3gp)</td>
1675 </tr>
1676 <tr>
1677 <td>AMR-WB</td>
1678 <td>REQUIRED<sup>3</sup></td>
1679 <td>REQUIRED<sup>3</sup></td>
1680 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1681 <td></td>
1682 </tr>
1683 <tr>
1684 <td>FLAC</td>
1685 <td></td>
1686 <td>REQUIRED <br>(Android 3.1+)</td>
1687 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1688recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1689does not include a low-pass filter). 16-bit recommended; no dither applied for
169024-bit.</td>
1691 <td>FLAC (.flac) only</td>
1692 </tr>
1693 <tr>
1694 <td>MP3</td>
1695 <td></td>
1696 <td>REQUIRED</td>
1697 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1698 <td>MP3 (.mp3)</td>
1699 </tr>
1700 <tr>
1701 <td>MIDI</td>
1702 <td></td>
1703 <td>REQUIRED</td>
1704 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1705ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1706 <td><ul>
1707 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1708 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1709 <li class="table_list">OTA (.ota)</li>
1710 <li class="table_list">iMelody (.imy)</li></ul></td>
1711 </tr>
1712 <tr>
1713 <td>Vorbis</td>
1714 <td></td>
1715 <td>REQUIRED</td>
1716 <td></td>
1717 <td><ul>
1718 <li class="table_list">Ogg (.ogg)</li>
1719 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1720 </tr>
1721 <tr>
1722 <td>PCM/WAVE</td>
1723 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1724 <td>REQUIRED</td>
1725 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1726sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1727frequencies.</td>
1728 <td>WAVE (.wav)</td>
1729 </tr>
1730 <tr>
1731 <td>Opus</td>
1732 <td></td>
1733 <td>REQUIRED<br> (Android 5.0+)</td>
1734 <td></td>
1735 <td>Matroska (.mkv)</td>
1736 </tr>
1737</table>
1738
1739
1740<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1741but optional for Android Watch device implementations.</p>
1742
1743<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17442 channels is optional.</p>
1745
1746<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1747
1748<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1749including Android Watch device implementations.</p>
1750
1751<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1752
1753<table>
1754 <tr>
1755 <th>Format/Codec</th>
1756 <th>Encoder</th>
1757 <th>Decoder</th>
1758 <th>Details</th>
1759 <th>Supported File Types/Container Formats</th>
1760 </tr>
1761 <tr>
1762 <td>JPEG</td>
1763 <td>REQUIRED</td>
1764 <td>REQUIRED</td>
1765 <td>Base+progressive</td>
1766 <td>JPEG (.jpg)</td>
1767 </tr>
1768 <tr>
1769 <td>GIF</td>
1770 <td></td>
1771 <td>REQUIRED</td>
1772 <td></td>
1773 <td>GIF (.gif)</td>
1774 </tr>
1775 <tr>
1776 <td>PNG</td>
1777 <td>REQUIRED</td>
1778 <td>REQUIRED</td>
1779 <td></td>
1780 <td>PNG (.png)</td>
1781 </tr>
1782 <tr>
1783 <td>BMP</td>
1784 <td></td>
1785 <td>REQUIRED</td>
1786 <td></td>
1787 <td>BMP (.bmp)</td>
1788 </tr>
1789 <tr>
1790 <td>WebP</td>
1791 <td>REQUIRED</td>
1792 <td>REQUIRED</td>
1793 <td></td>
1794 <td>WebP (.webp)</td>
1795 </tr>
1796</table>
1797
1798
1799<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1800
1801<p>Video codecs are optional for Android Watch device implementations.</p>
1802
1803<table>
1804 <tr>
1805 <th>Format/Codec</th>
1806 <th>Encoder</th>
1807 <th>Decoder</th>
1808 <th>Details</th>
1809 <th>Supported File Types/<br>Container Formats</th>
1810 </tr>
1811 <tr>
1812 <td>H.263</td>
1813 <td>REQUIRED<sup>1</sup></td>
1814 <td>REQUIRED<sup>2</sup></td>
1815 <td></td>
1816 <td><ul>
1817 <li class="table_list">3GPP (.3gp)</li>
1818 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1819 </tr>
1820 <tr>
1821 <td>H.264 AVC</td>
1822 <td>REQUIRED<sup>2</sup></td>
1823 <td>REQUIRED<sup>2</sup></td>
1824 <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>
1825 <td><ul>
1826 <li class="table_list">3GPP (.3gp)</li>
1827 <li class="table_list">MPEG-4 (.mp4)</li>
1828 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1829 </tr>
1830 <tr>
1831 <td>H.265 HEVC</td>
1832 <td></td>
1833 <td>REQUIRED<sup>5</sup></td>
1834 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1835 <td>MPEG-4 (.mp4)</td>
1836 </tr>
1837 <tr>
1838 <td>MPEG-4 SP</td>
1839 <td></td>
1840 <td>REQUIRED<sup>2</sup></td>
1841 <td></td>
1842 <td>3GPP (.3gp)</td>
1843 </tr>
1844 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1845 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1846 <td>REQUIRED<sup>2</sup></p>
1847
1848<p>(Android 4.3+)</td>
1849 <td>REQUIRED<sup>2</sup></p>
1850
1851<p>(Android 2.3.3+)</td>
1852 <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>
1853 <td><ul>
1854 <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]1855 <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]1856 </tr>
1857 <tr>
1858 <td>VP9</td>
1859 <td></td>
1860 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1861 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1862 <td><ul>
1863 <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]1864 <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]1865 </tr>
1866</table>
1867
1868
1869<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1870android.hardware.camera or android.hardware.camera.front.</p>
1871
1872<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1873
1874<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1875device implementations SHOULD use a hardware VP8 codec that meets the
1876requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1877
1878<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1879
1880<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1881
1882<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1883
1884<div class="note">
1885<p>Video codecs are optional for Android Watch device implementations.</p>
1886</div>
1887
1888
1889<p>Android device implementations with H.264 codec support, MUST support Baseline
1890Profile Level 3 and the following SD (Standard Definition) video encoding
1891profiles and SHOULD support Main Profile Level 4 and the following HD (High
1892Definition) video encoding profiles. Android Television devices are STRONGLY
1893RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1894<table>
1895 <tr>
1896 <th></th>
1897 <th>SD (Low quality)</th>
1898 <th>SD (High quality)</th>
1899 <th>HD 720p1</th>
1900 <th>HD 1080p1</th>
1901 </tr>
1902 <tr>
1903 <th>Video resolution</th>
1904 <td>320 x 240 px</td>
1905 <td>720 x 480 px</td>
1906 <td>1280 x 720 px</td>
1907 <td>1920 x 1080 px</td>
1908 </tr>
1909 <tr>
1910 <th>Video frame rate</th>
1911 <td>20 fps</td>
1912 <td>30 fps</td>
1913 <td>30 fps</td>
1914 <td>30 fps</td>
1915 </tr>
1916 <tr>
1917 <th>Video bitrate</th>
1918 <td>384 Kbps</td>
1919 <td>2 Mbps</td>
1920 <td>4 Mbps</td>
1921 <td>10 Mbps</td>
1922 </tr>
1923</table>
1924
1925
1926<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1927devices.</p>
1928
1929<p>Android device implementations with VP8 codec support MUST support the SD video
1930encoding profiles and SHOULD support the following HD (High Definition) video
1931encoding profiles.</p>
1932<table>
1933 <tr>
1934 <th></th>
1935 <th>SD (Low quality)</th>
1936 <th>SD (High quality)</th>
1937 <th>HD 720p1</th>
1938 <th>HD 1080p1</th>
1939 </tr>
1940 <tr>
1941 <th>Video resolution</th>
1942 <td>320 x 180 px</td>
1943 <td>640 x 360 px</td>
1944 <td>1280 x 720 px</td>
1945 <td>1920 x 1080 px</td>
1946 </tr>
1947 <tr>
1948 <th>Video frame rate</th>
1949 <td>30 fps</td>
1950 <td>30 fps</td>
1951 <td>30 fps</td>
1952 <td>30 fps</td>
1953 </tr>
1954 <tr>
1955 <th>Video bitrate</th>
1956 <td>800 Kbps </td>
1957 <td>2 Mbps</td>
1958 <td>4 Mbps</td>
1959 <td>10 Mbps</td>
1960 </tr>
1961</table>
1962
1963<p class="table_footnote">1 When supported by hardware.</p>
1964
1965<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1966
1967<div class="note">
1968<p>Video codecs are optional for Android Watch device implementations.</p>
1969</div>
1970
1971
1972<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1973the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1974standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1975
1976<p>Android device implementations with H.264 decoders, MUST support Baseline
1977Profile Level 3 and the following SD video decoding profiles and SHOULD support
1978the HD decoding profiles. Android Television devices MUST support High Profile
1979Level 4.2 and the HD 1080p decoding profile.</p>
1980<table>
1981 <tr>
1982 <th></th>
1983 <th>SD (Low quality)</th>
1984 <th>SD (High quality)</th>
1985 <th>HD 720p1</th>
1986 <th>HD 1080p1</th>
1987 </tr>
1988 <tr>
1989 <th>Video resolution</th>
1990 <td>320 x 240 px</td>
1991 <td>720 x 480 px</td>
1992 <td>1280 x 720 px</td>
1993 <td>1920 x 1080 px</td>
1994 </tr>
1995 <tr>
1996 <th>Video frame rate</th>
1997 <td>30 fps</td>
1998 <td>30 fps</td>
1999 <td>30 fps / 60 fps2</td>
2000 <td>30 fps / 60 fps2</td>
2001 </tr>
2002 <tr>
2003 <th>Video bitrate</th>
2004 <td>800 Kbps </td>
2005 <td>2 Mbps</td>
2006 <td>8 Mbps</td>
2007 <td>20 Mbps</td>
2008 </tr>
2009</table>
2010
2011
2012<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2013types only when supported by hardware.</p>
2014
2015<p class="table_footnote">2 Required for Android Television device implementations.</p>
2016
2017<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
2018decoding profiles. Android Television devices MUST support the HD 1080p
2019decoding profile. </p>
2020<table>
2021 <tr>
2022 <th></th>
2023 <th>SD (Low quality)</th>
2024 <th>SD (High quality)</th>
2025 <th>HD 720p1</th>
2026 <th>HD 1080p1</th>
2027 </tr>
2028 <tr>
2029 <th>Video resolution</th>
2030 <td>320 x 180 px</td>
2031 <td>640 x 360 px</td>
2032 <td>1280 x 720 px</td>
2033 <td>1920 x 1080 px</td>
2034 </tr>
2035 <tr>
2036 <th>Video frame rate</th>
2037 <td>30 fps</td>
2038 <td>30 fps</td>
2039 <td>30 fps / 60 fps2</td>
2040 <td>30 / 60 fps2</td>
2041 </tr>
2042 <tr>
2043 <th>Video bitrate</th>
2044 <td>800 Kbps </td>
2045 <td>2 Mbps</td>
2046 <td>8 Mbps</td>
2047 <td>20 Mbps</td>
2048 </tr>
2049</table>
2050
2051
2052<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2053devices only when supported by hardware.</p>
2054
2055<p class="table_footnote">2 Required for Android Television device implementations.</p>
2056
2057<p>Android device implementations, when supporting 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
2058HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2059support the HD 1080p decoding profile and SHOULD support the UHD decoding
2060profile. When the UHD video decoding profile is supported, it MUST support 8
2061bit color depth.</p>
2062<table>
2063 <tr>
2064 <th></th>
2065 <th>SD (Low quality)</th>
2066 <th>SD (High quality)</th>
2067 <th>HD 720p 1</th>
2068 <th>HD 1080p 2</th>
2069 <th>UHD 2</th>
2070 </tr>
2071 <tr>
2072 <th>Video resolution</th>
2073 <td>320 x 180 px</td>
2074 <td>640 x 360 px</td>
2075 <td>1280 x 720 px</td>
2076 <td>1920 x 1080 px</td>
2077 <td>3840 x 2160 px</td>
2078 </tr>
2079 <tr>
2080 <th>Video frame rate</th>
2081 <td>30 fps</td>
2082 <td>30 fps</td>
2083 <td>30 fps</td>
2084 <td>30 fps</td>
2085 <td>30 fps</td>
2086 </tr>
2087 <tr>
2088 <th>Video bitrate</th>
2089 <td>600 Kbps </td>
2090 <td>1.6 Mbps</td>
2091 <td>4 Mbps</td>
2092 <td>10 Mbps</td>
2093 <td>20 Mbps</td>
2094 </tr>
2095</table>
2096
2097
2098<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2099devices only when supported by hardware.</p>
2100
2101<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2102supported by hardware.</p>
2103
2104<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
2105decoding profiles and SHOULD support the HD decoding profiles. Android
2106Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21071080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2108the UHD decoding profile.</p>
2109<table>
2110 <tr>
2111 <th></th>
2112 <th>SD (Low quality)</th>
2113 <th>SD (High quality)</th>
2114 <th>HD 720p </strong>1 </td>
2115 <th>HD 1080p </strong>1 </td>
2116 <th>UHD </strong>2</td>
2117 </tr>
2118 <tr>
2119 <th>Video resolution</th>
2120 <td>352 x 288 px</td>
2121 <td>640 x 360 px</td>
2122 <td>1280 x 720 px</td>
2123 <td>1920 x 1080 px</td>
2124 <td>3840 x 2160 px</td>
2125 </tr>
2126 <tr>
2127 <th>Video frame rate</th>
2128 <td>30 fps</td>
2129 <td>30 fps</td>
2130 <td>30 fps</td>
2131 <td>30 fps</td>
2132 <td>30 fps</td>
2133 </tr>
2134 <tr>
2135 <th>Video bitrate</th>
2136 <td>600 Kbps </td>
2137 <td>1.6 Mbps</td>
2138 <td>4 Mbps</td>
2139 <td>10 Mbps</td>
2140 <td>20 Mbps</td>
2141 </tr>
2142</table>
2143
2144
2145<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2146devices only when supported by hardware.</p>
2147
2148<p class="table_footnote">2 Required for Android Television device implementations when supported by
2149hardware.</p>
2150
2151<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2152
2153
2154<p>While some of the requirements outlined in this section are stated as SHOULD
2155since Android 4.3, the Compatibility Definition for a future version is planned
2156to 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
2157compatibility when upgraded to the future version.</p>
2158
2159<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2160
2161
2162<p>Device implementations that declare android.hardware.microphone MUST allow
2163capture of raw audio content with the following characteristics:</p>
2164
2165<ul>
2166 <li><strong>Format</strong>: Linear PCM, 16-bit
2167 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2168 <li><strong>Channels</strong>: Mono
2169</ul>
2170
2171<p>Device implementations that declare android.hardware.microphone SHOULD allow
2172capture of raw audio content with the following characteristics:</p>
2173
2174<ul>
2175 <li><strong>Format</strong>: Linear PCM, 16-bit
2176 <li><strong>Sampling rates</strong>: 22050, 48000
2177 <li><strong>Channels</strong>: Stereo
2178</ul>
2179
2180<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2181
2182
2183<p>In addition to the above recording specifications, when an application has
2184started recording an audio stream using the
2185android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2186
2187<ul>
2188 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2189characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2190 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2191source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2192 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2193dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2194 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2195level at the microphone.
2196 <li>Noise reduction processing, if present, MUST be disabled.
2197 <li>Automatic gain control, if present, MUST be disabled
2198</ul>
2199
2200<p>If the platform supports noise suppression technologies tuned for speech
2201recognition, the effect MUST be controllable from the
2202android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2203noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2204of the noise suppression technology.</p>
2205
2206<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2207
2208
2209<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2210audio source. Devices that declare android.hardware.audio.output MUST properly
2211implement the REMOTE_SUBMIX audio source so that when an application uses the
2212android.media.AudioRecord API to record from this audio source, it can capture
2213a mix of all audio streams except for the following:</p>
2214
2215<ul>
2216 <li>STREAM_RING
2217 <li>STREAM_ALARM
2218 <li>STREAM_NOTIFICATION
2219</ul>
2220
2221<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2222
2223
2224<p>Device implementations that declare android.hardware.audio.output MUST conform
2225to the requirements in this section.</p>
2226
2227<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2228
2229
2230<p>The device MUST allow playback of raw audio content with the following
2231characteristics:</p>
2232
2233<ul>
2234 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2235 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2236 <li><strong>Channels</strong>: Mono, Stereo</li>
2237</ul>
2238
2239<p>The device SHOULD allow playback of raw audio content with the following
2240characteristics:</p>
2241
2242<ul>
2243 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2244</ul>
2245
2246<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2247
2248
2249<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
2250android.hardware.audio.output:</p>
2251
2252<ul>
2253 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2254implementations controllable through the AudioEffect subclasses Equalizer,
2255LoudnessEnhancer.</li>
2256 <li>MUST support the visualizer API implementation, controllable through the
2257Visualizer class.</li>
2258 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2259EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2260controllable through the AudioEffect sub-classes BassBoost,
2261EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2262</ul>
2263
2264<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2265
2266
2267<p>Android Television device implementations MUST include support for system
2268Master Volume and digital audio output volume attenuation on supported outputs,
2269except for compressed audio passthrough output (where no audio decoding is done
2270on the device).</p>
2271
2272<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2273
2274
2275<p>Audio latency is the time delay as an audio signal passes through a system.
2276Many classes of applications rely on short latencies, to achieve real-time
2277sound effects.</p>
2278
2279<p>For the purposes of this section, use the following definitions:</p>
2280
2281<ul>
2282 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2283when the corresponding sound can be heard by an external listener or observed
2284by a transducer.</li>
2285 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2286idle and powered down prior to the request.</li>
2287 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2288 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2289when an application reads the corresponding frame of PCM-coded data.</li>
2290 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2291audio input system has been idle and powered down prior to the request.</li>
2292 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2293 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2294 <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]2295 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2296 one buffer period.
2297 The buffer period term allows processing time for the app and for the app to
2298 mitigate phase difference between input and output streams.
2299 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2300 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2301NDK_root/docs/opensles/index.html.</li>
2302</ul>
2303
2304<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2305or exceed these audio output requirements:</p>
2306
2307<ul>
2308 <li>cold output latency of 100 milliseconds or less</li>
2309 <li>continuous output latency of 45 milliseconds or less</li>
2310 <li>minimize the cold output jitter</li>
2311</ul>
2312
2313<p>If a device implementation meets the requirements of this section after any
2314initial calibration when using the OpenSL ES PCM buffer queue API, for
2315continuous output latency and cold output latency over at least one supported
2316audio output device, it MAY report support for low-latency audio, by reporting
2317the feature android.hardware.audio.low_latency via the
2318android.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
2319MUST NOT report support for low-latency audio.</p>
2320
2321<p>Device implementations that include android.hardware.microphone SHOULD meet
2322these input audio requirements:</p>
2323
2324<ul>
2325 <li>cold input latency of 100 milliseconds or less</li>
2326 <li>continuous input latency of 30 milliseconds or less</li>
2327 <li>continuous round-trip latency of 50 milliseconds or less</li>
2328 <li>minimize the cold input jitter</li>
2329</ul>
2330
2331<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2332
2333
2334<p>Devices MUST support the media network protocols for audio and video playback
2335as 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>
2336
2337<ul>
2338 <li>RTSP (RTP, SDP)</li>
2339 <li>HTTP(S) progressive streaming</li>
2340 <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>
2341</ul>
2342
2343<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2344
2345
2346<p>Device implementations that support secure video output and are capable of
2347supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2348implementations that declare support for Display.FLAG_SECURE, if they support a
2349wireless display protocol, MUST secure the link with a cryptographically strong
2350mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2351if they support a wired external display, the device implementations MUST
2352support HDCP 1.2 or higher. Android Television device implementations MUST
2353support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2354lower resolutions. The upstream Android open source implementation includes
2355support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2356requirement.</p>
2357
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2358<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2359
2360<p>
2361If a device implementation supports the inter-app MIDI software transport
2362(virtual MIDI devices), and it supports MIDI over
2363<em>all</em> of the following MIDI-capable hardware transports
2364for which it provides generic non-MIDI connectivity, it MAY report
2365support for feature android.software.midi via the
2366android.content.pm.PackageManager class
2367[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2368</p>
2369
2370<p>The MIDI-capable hardware transports are:</p>
2371<ul>
2372 <li>USB host mode (section 7.7 USB)</li>
2373 <li>USB peripheral mode (section 7.7 USB)</li>
2374</ul>
2375
2376<p>
2377Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2378MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2379it MUST NOT report support for feature android.software.midi.
2380</p>
2381
2382<p>
2383MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2384is in trial use status. A device implementation that reports
2385feature android.software.midi, and which provides generic non-MIDI connectivity
2386over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2387</p>
2388
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2389<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2390
2391<p>
2392If a device implementation meets <em>all</em> of the following requirements,
2393it MAY report support for feature android.hardware.audio.pro via the
2394android.content.pm.PackageManager class
2395[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2396</p>
2397
2398<ul>
2399
2400<li>
2401The device implementation MUST support android.hardware.audio.low_latency
2402</li>
2403
2404<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2405MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2406supported path.
2407</li>
2408
2409<li>
2410If the device implementation includes a 4 conductor 3.5mm audio jack,
2411the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2412and SHOULD be 10 milliseconds or less over at the audio jack path.
2413</li>
2414
2415<li>
2416The device implementation MUST include a USB port(s) supporting USB host mode and
2417USB peripheral mode.
2418</li>
2419
2420<li>
2421The USB host mode MUST implement the USB audio class and handle concurrent input/output with
2422a USB audio class-compliant peripheral having the following minimum capabilities:
2423<ul>
2424<li>4-channel input</li>
2425<li>4-channel output</li>
2426<li>24-bit depth PCM</li>
2427<li>96 kHz sample rate</li>
2428</ul>
2429</li>
2430
2431<li>
2432If the device includes an HDMI port, the device implementation
2433MUST support output in stereo and 8 channels
2434at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2435</li>
2436
2437<li>
2438The device implementation MUST report support for feature android.software.midi.
2439</li>
2440
2441</ul>
2442
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2443<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2444
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2445<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2446
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2447<p>Device implementations MUST support the Android Developer Tools provided in the
2448Android SDK. Android compatible devices MUST be compatible with:</p>
2449
2450<ul>
2451 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2452</ul>
2453
2454<p>Device implementations MUST support all adb functions as documented in the
2455Android 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
2456user-accessible mechanism to turn on the Android Debug Bridge. If a device
2457implementation omits USB peripheral mode, it MUST implement the Android Debug
2458Bridge via local-area network (such as Ethernet or 802.11). </p>
2459
2460<p>Android includes support for secure adb. Secure adb enables adb on known
2461authenticated hosts. Device implementations MUST support secure adb.</p>
2462
2463<ul>
2464 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2465</ul>
2466
2467<p>Device implementations MUST support all ddms features as documented in the
2468Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2469but MUST be supported whenever the user has activated the Android Debug Bridge,
2470as above.</p>
2471
2472<ul>
2473 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2474</ul>
2475
2476<p>Device implementations MUST include the Monkey framework, and make it available
2477for applications to use.</p>
2478
2479<ul>
2480 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2481</ul>
2482
2483<p>Device implementations MUST support systrace tool as documented in the Android
2484SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2485mechanism to turn on Systrace.</p>
2486
2487<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2488using the standard Android SDK tools, without additional support; however
2489Microsoft Windows systems typically require a driver for new Android devices.
2490(For instance, new vendor IDs and sometimes new device IDs require custom USB
2491drivers for Windows systems.) If a device implementation is unrecognized by the
2492adb tool as provided in the standard Android SDK, device implementers MUST
2493provide Windows drivers allowing developers to connect to the device using the
2494adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2495Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2496
2497<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2498
2499
2500<p>Android includes support for developers to configure application
2501development-related settings. Device implementations MUST honor the
2502android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2503development-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
2504default and enables users to launch Developer Options after pressing seven (7)
2505times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2506Developer Options. Specifically, device implementations MUST hide Developer
2507Options by default and MUST provide a mechanism to enable Developer Options
2508that is consistent with the upstream Android implementation.</p>
2509
2510<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2511
2512
2513<p>If a device includes a particular hardware component that has a corresponding
2514API for third-party developers, the device implementation MUST implement that
2515API as described in the Android SDK documentation. If an API in the SDK
2516interacts with a hardware component that is stated to be optional and the
2517device implementation does not possess that component:</p>
2518
2519<ul>
2520 <li>Complete class definitions (as documented by the SDK) for the component APIs
2521MUST still be presented.
2522 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2523 <li>API methods MUST return null values where permitted by the SDK documentation.
2524 <li>API methods MUST return no-op implementations of classes where null values are
2525not permitted by the SDK documentation.
2526 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2527</ul>
2528
2529<p>A typical example of a scenario where these requirements apply is the telephony
2530API: even on non-phone devices, these APIs must be implemented as reasonable
2531no-ops.</p>
2532
2533<p>Device implementations MUST consistently report accurate hardware configuration
2534information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2535methods on the android.content.pm.PackageManager class for the same build
2536fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2537
2538<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2539
2540
2541<p>Android includes facilities that automatically adjust application assets and UI
2542layouts appropriately for the device, to ensure that third-party applications
2543run 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
2544this section.</p>
2545
2546<p>The units referenced by the requirements in this section are defined as
2547follows:</p>
2548
2549<ul>
2550 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2551of the display.</li>
2552 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
25531&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2554within the range.</li>
2555 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2556 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2557 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2558 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2559dps * (density/160).</li>
2560</ul>
2561
2562<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2563
2564
2565<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2566
2567<div class="note">
2568<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>
2569</div>
2570
2571<p>The Android UI framework supports a variety of different screen sizes, and
2572allows applications to query the device screen size (aka &ldquo;screen layout") via
2573android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2574Device implementations MUST report the correct screen size as defined in the
2575Android 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
2576implementations MUST report the correct screen size according to the following
2577logical density-independent pixel (dp) screen dimensions.</p>
2578
2579<ul>
2580 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2581is an Android Watch device.</li>
2582 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2583dp x 320 dp.</li>
2584 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2585dp x 480 dp.</li>
2586 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2587dp x 720 dp.</li>
2588</ul>
2589
2590<p>In addition, </p>
2591
2592<ul>
2593 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2594range from 1.1 to 2.5 inches.</li>
2595 <li>Other types of Android device implementations, with a physically integrated
2596screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2597</ul>
2598
2599<p>Devices MUST NOT change their reported screen size at any time.</p>
2600
2601<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2602&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2603implementations MUST correctly honor applications' stated support for small,
2604normal, large, and xlarge screens, as described in the Android SDK
2605documentation.</p>
2606
2607<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2608
2609<div class="note">
2610<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2611</div>
2612
2613
2614<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
261516:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2616such a device implementation will use a UI_MODE_TYPE_WATCH as the
2617android.content.res.Configuration.uiMode.</p>
2618
2619<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2620
2621
2622<p>The Android UI framework defines a set of standard logical densities to help
2623application developers target application resources. Device implementations
2624MUST report only one of the following logical Android framework densities
2625through the android.util.DisplayMetrics APIs, and MUST execute applications at
2626this standard density and MUST NOT change the value at at any time for the
2627default display.</p>
2628
2629<ul>
2630 <li>120 dpi (ldpi)</li>
2631 <li>160 dpi (mdpi)</li>
2632 <li>213 dpi (tvdpi)</li>
2633 <li>240 dpi (hdpi)</li>
2634 <li>280 dpi (280dpi)</li>
2635 <li>320 dpi (xhdpi)</li>
2636 <li>400 dpi (400dpi)</li>
2637 <li>480 dpi (xxhdpi)</li>
2638 <li>560 dpi (560dpi)</li>
2639 <li>640 dpi (xxxhdpi)</li>
2640</ul>
2641
2642<p>Device implementations SHOULD define the standard Android framework density
2643that is numerically closest to the physical density of the screen, unless that
2644logical density pushes the reported screen size below the minimum supported. If
2645the standard Android framework density that is numerically closest to the
2646physical density results in a screen size that is smaller than the smallest
2647supported compatible screen size (320 dp width), device implementations SHOULD
2648report the next lowest standard Android framework density.</p>
2649
2650<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2651
2652
2653<p>Device implementations MUST report correct values for all display metrics
2654defined 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
2655external screen is used as the default display.</p>
2656
2657<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2658
2659
2660<p>Devices MUST report which screen orientations they support
2661(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2662MUST report at least one supported orientation. For example, a device with a
2663fixed orientation landscape screen, such as a television or laptop, SHOULD only
2664report android.hardware.screen.landscape.</p>
2665
2666<p>Devices that report both screen orientations MUST support dynamic orientation
2667by applications to either portrait or landscape screen orientation. That is,
2668the device must respect the application&rsquo;s request for a specific screen
2669orientation. Device implementations MAY select either portrait or landscape
2670orientation as the default.</p>
2671
2672<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2673whenever queried via the android.content.res.Configuration.orientation,
2674android.view.Display.getOrientation(), or other APIs.</p>
2675
2676<p>Devices MUST NOT change the reported screen size or density when changing
2677orientation.</p>
2678
2679<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2680
2681
2682<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2683detailed in the Android SDK documentations. Device implementations SHOULD
2684support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2685implementations MUST also support Android RenderScript, as detailed in the
2686Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2687
2688<p>Device implementations MUST also correctly identify themselves as supporting
2689OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2690
2691<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2692 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2693for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2694 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2695libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2696ES 2.0.</li>
2697 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2698support the corresponding managed APIs and include support for native C/C++
2699APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2700libGLESv2.so MUST export the corresponding function symbols in addition to the
2701OpenGL ES 2.0 function symbols.</li>
2702</ul>
2703
2704<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2705interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2706and the ASTC texture compression format. Android device implementations MAY
2707support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2708support through the android.hardware.opengles.aep feature flag.</p>
2709
2710<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2711However, device implementations MUST report via the OpenGL ES managed and
2712native APIs all extension strings that they do support, and conversely MUST NOT
2713report extension strings that they do not support.</p>
2714
2715<p>Note that Android includes support for applications to optionally specify that
2716they require specific OpenGL texture compression formats. These formats are
2717typically vendor-specific. Device implementations are not required by Android
2718to implement any specific texture compression format. However, they SHOULD
2719accurately report any texture compression formats that they do support, via the
2720getString() method in the OpenGL API.</p>
2721
2722<p>Android includes a mechanism for applications to declare that they want to
2723enable hardware acceleration for 2D graphics at the Application, Activity,
2724Window, or View level through the use of a manifest tag
2725android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2726
2727<p>Device implementations MUST enable hardware acceleration by default, and MUST
2728disable hardware acceleration if the developer so requests by setting
2729android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2730through the Android View APIs.</p>
2731
2732<p>In addition, device implementations MUST exhibit behavior consistent with the
2733Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2734
2735<p>Android includes a TextureView object that lets developers directly integrate
2736hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2737Device implementations MUST support the TextureView API, and MUST exhibit
2738consistent behavior with the upstream Android implementation.</p>
2739
2740<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2741that indicates whether the EGLConfig supports rendering to an ANativeWindow
2742that records images to a video. Device implementations MUST support
2743EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2744
2745<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2746
2747
2748<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2749'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2750applications not developed for old versions of Android that pre-date
2751screen-size independence.</p>
2752
2753<ul>
2754<li>Android Automotive does not support legacy compatibility mode.</li>
2755<li>All other device implementations MUST include support for legacy application
2756compatibility mode as implemented by the upstream Android open source code. That
2757is, device implementations MUST NOT alter the triggers or thresholds at which
2758compatibility mode is activated, and MUST NOT alter the behavior of the
2759compatibility mode itself.</li>
2760</ul>
2761
2762<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2763
2764
2765<p>The Android platform includes APIs that allow applications to render rich
2766graphics to the display. Devices MUST support all of these APIs as defined by
2767the Android SDK unless specifically allowed in this document. </p>
2768
2769<ul>
2770 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2771SHOULD support displays capable of 24-bit color graphics.</li>
2772 <li>Devices MUST support displays capable of rendering animations.</li>
2773 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2774and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
277515% tolerance.</li>
2776</ul>
2777
2778<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2779
2780
2781<p>Android includes support for secondary display to enable media sharing
2782capabilities and developer APIs for accessing external displays. If a device
2783supports an external display either via a wired, wireless, or an embedded
2784additional display connection then the device implementation MUST implement the
2785display 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>
2786
2787<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2788
2789<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2790for non-touch navigation.</p>
2791
2792<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2793
2794<div class="note">
2795<p>Android Watch and Android Automotive implementations MAY implement a soft
2796keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2797</div>
2798
2799
2800<p>Device implementations:</p>
2801
2802<ul>
2803 <li>MUST include support for the Input Management Framework (which allows
2804third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2805detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2806 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2807hard keyboard is present) except for Android Watch devices where the screen
2808size makes it less reasonable to have a soft keyboard.</li>
2809 <li>MAY include additional soft keyboard implementations.</li>
2810 <li>MAY include a hardware keyboard.</li>
2811 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2812specified 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>
2813</ul>
2814
2815<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2816
2817<div class="note">
2818<p>Android Television devices MUST support D-pad.</p>
2819</div>
2820
2821<p>Device implementations:</p>
2822
2823<ul>
2824 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2825device implementation is not an Android Television device.</li>
2826 <li>MUST report the correct value for android.content.res.Configuration.navigation
2827[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2828 <li>MUST provide a reasonable alternative user interface mechanism for the
2829selection and editing of text, compatible with Input Management Engines. The
2830upstream Android open source implementation includes a selection mechanism
2831suitable for use with devices that lack non-touch navigation inputs.</li>
2832</ul>
2833
2834<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2835
2836<div class="note">
2837<p>The availability and visibility requirement of the Home, Recents, and Back
2838functions differ between device types as described in this section.</p>
2839</div>
2840
2841<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2842KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2843navigation paradigm and therefore:</p>
2844
2845<ul>
2846 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2847Back functions.</li>
2848 <li>Android Television device implementations MUST provide the Home and Back
2849functions.</li>
2850 <li>Android Watch device implementations MUST have the Home function available to
2851the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2852 <li>Android Automotive implementations MUST provide the Home function and MAY
2853provide Back and Recent functions.</li>
2854 <li>All other types of device implementations MUST provide the Home and Back
2855functions.</li>
2856</ul>
2857
2858<p>These functions MAY be implemented via dedicated physical buttons (such as
2859mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2860software keys on a distinct portion of the screen, gestures, touch panel, etc.
2861Android supports both implementations. All of these functions MUST be
2862accessible with a single action (e.g. tap, double-click or gesture) when
2863visible.</p>
2864
2865<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2866together with other navigation functions in full-screen mode. This does not
2867apply to devices upgrading from earlier Android versions that have physical
2868buttons for navigation and no recents key.</p>
2869
2870<p> The Home and Back functions, if provided, MUST each have a visible button or
2871icon unless hidden together with other navigation functions in full-screen mode
2872or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2873
2874<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2875Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2876implement a dedicated physical button for the Menu function. Older device
2877implementations SHOULD NOT implement a dedicated physical button for the Menu
2878function, but if the physical Menu button is implemented and the device is
2879running applications with targetSdkVersion > 10, the device implementation:</p>
2880
2881<ul>
2882 <li>MUST display the action overflow button on the action bar when it is visible
2883and the resulting action overflow menu popup is not empty. For a device
2884implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2885is RECOMMENDED.</li>
2886 <li>MUST NOT modify the position of the action overflow popup displayed by
2887selecting the overflow button in the action bar.</li>
2888 <li>MAY render the action overflow popup at a modified position on the screen when
2889it is displayed by selecting the physical menu button.</li>
2890</ul>
2891
2892<p>For backwards compatibility, device implementations MUST make the Menu function
2893available to applications when targetSdkVersion is less than 10, either by a physical
2894button, a software key, or gestures. This Menu function should be presented
2895unless hidden together with other navigation functions.</p>
2896
2897<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
2898the Assist action available to the user at all times when running applications.
2899The Assist action SHOULD be implemented as a long-press on the Home button or a
2900swipe-up gesture on the software Home key. This function MAY be implemented via
2901another physical button, software key, or gesture, but MUST be accessible with
2902a single action (e.g. tap, double-click, or gesture) when other navigation keys
2903are visible.</p>
2904
2905<p>Device implementations MAY use a distinct portion of the screen to display the
2906navigation keys, but if so, MUST meet these requirements:</p>
2907
2908<ul>
2909 <li>Device implementation navigation keys MUST use a distinct portion of the
2910screen, not available to applications, and MUST NOT obscure or otherwise
2911interfere with the portion of the screen available to applications.</li>
2912 <li>Device implementations MUST make available a portion of the display to
2913applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2914 <li>Device implementations MUST display the navigation keys when applications do
2915not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2916 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2917profile&rdquo; (eg. dimmed) mode when applications specify
2918SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2919 <li>Device implementations MUST hide the navigation keys when applications specify
2920SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2921</ul>
2922
2923<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2924
2925<div class="note">
2926<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2927</div>
2928
2929
2930<p>Device implementations SHOULD have a pointer input system of some kind (either
2931mouse-like or touch). However, if a device implementation does not support a
2932pointer input system, it MUST NOT report the android.hardware.touchscreen or
2933android.hardware.faketouch feature constant. Device implementations that do
2934include a pointer input system:</p>
2935
2936<ul>
2937 <li>SHOULD support fully independently tracked pointers, if the device input system
2938supports multiple pointers.</li>
2939 <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>
2940</ul>
2941
2942<p>Android includes support for a variety of touchscreens, touch pads, and fake
2943touch input devices. Touchscreen based device implementations are associated
2944with 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
2945screen. Since the user is directly touching the screen, the system does not
2946require any additional affordances to indicate the objects being manipulated.
2947In contrast, a fake touch interface provides a user input system that
2948approximates a subset of touchscreen capabilities. For example, a mouse or
2949remote control that drives an on-screen cursor approximates touch, but requires
2950the user to first point or focus then click. Numerous input devices like the
2951mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2952trackpad can support fake touch interactions. Android includes the feature
2953constant android.hardware.faketouch, which corresponds to a high-fidelity
2954non-touch (pointer-based) input device such as a mouse or trackpad that can
2955adequately emulate touch-based input (including basic gesture support), and
2956indicates that the device supports an emulated subset of touchscreen
2957functionality. Device implementations that declare the fake touch feature MUST
2958meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2959
2960<p>Device implementations MUST report the correct feature corresponding to the
2961type of input used. Device implementations that include a touchscreen
2962(single-touch or better) MUST report the platform feature constant
2963android.hardware.touchscreen. Device implementations that report the platform
2964feature constant android.hardware.touchscreen MUST also report the platform
2965feature constant android.hardware.faketouch. Device implementations that do not
2966include a touchscreen (and rely on a pointer device only) MUST NOT report any
2967touchscreen feature, and MUST report only android.hardware.faketouch if they
2968meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2969
2970<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2971
2972
2973<p>Device implementations that declare support for android.hardware.faketouch:</p>
2974
2975<ul>
2976 <li>MUST report the absolute X and Y screen positions of the pointer location and
2977display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2978 <li>MUST report touch event with the action code that specifies the state change
2979that 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>
2980 <li>MUST support pointer down and up on an object on the screen, which allows users
2981to emulate tap on an object on the screen.</li>
2982 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2983place on an object on the screen within a time threshold, which allows users to
2984emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2985 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2986any other arbitrary point on the screen, followed by a pointer up, which allows
2987users to emulate a touch drag.</li>
2988 <li>MUST support pointer down then allow users to quickly move the object to a
2989different position on the screen and then pointer up on the screen, which
2990allows users to fling an object on the screen.</li>
2991</ul>
2992
2993<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2994MUST meet the requirements for faketouch above, and MUST also support distinct
2995tracking of two or more independent pointer inputs.</p>
2996
2997<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
2998
2999
3000<p>Android Television device implementations MUST support button mappings for game
3001controllers as listed below. The upstream Android implementation includes
3002implementation for game controllers that satisfies this requirement. </p>
3003
3004<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3005
3006
3007<p>Android Television device implementations MUST support the following key
3008mappings:</p>
3009<table>
3010 <tr>
3011 <th>Button</th>
3012 <th>HID Usage</strong><sup>2</sup></td>
3013 <th>Android Button</th>
3014 </tr>
3015 <tr>
3016 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3017 <td>0x09 0x0001</td>
3018 <td>KEYCODE_BUTTON_A (96)</td>
3019 </tr>
3020 <tr>
3021 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3022 <td>0x09 0x0002</td>
3023 <td>KEYCODE_BUTTON_B (97)</td>
3024 </tr>
3025 <tr>
3026 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3027 <td>0x09 0x0004</td>
3028 <td>KEYCODE_BUTTON_X (99)</td>
3029 </tr>
3030 <tr>
3031 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3032 <td>0x09 0x0005</td>
3033 <td>KEYCODE_BUTTON_Y (100)</td>
3034 </tr>
3035 <tr>
3036 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
3037
3038<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]3039 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3040 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3041 </tr>
3042 <tr>
3043 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3044
3045<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]3046 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3047 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3048 </tr>
3049 <tr>
3050 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3051 <td>0x09 0x0007</td>
3052 <td>KEYCODE_BUTTON_L1 (102)</td>
3053 </tr>
3054 <tr>
3055 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3056 <td>0x09 0x0008</td>
3057 <td>KEYCODE_BUTTON_R1 (103)</td>
3058 </tr>
3059 <tr>
3060 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3061 <td>0x09 0x000E</td>
3062 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3063 </tr>
3064 <tr>
3065 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3066 <td>0x09 0x000F</td>
3067 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3068 </tr>
3069 <tr>
3070 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3071 <td>0x0c 0x0223</td>
3072 <td>KEYCODE_HOME (3)</td>
3073 </tr>
3074 <tr>
3075 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3076 <td>0x0c 0x0224</td>
3077 <td>KEYCODE_BACK (4)</td>
3078 </tr>
3079</table>
3080
3081
3082<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3083
3084<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3085
3086<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3087Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3088Report Size of 4. The logical value is defined to be the clockwise rotation
3089away from the vertical axis; for example, a logical value of 0 represents no
3090rotation and the up button being pressed, while a logical value of 1 represents
3091a rotation of 45 degrees and both the up and left keys being pressed.</p>
3092
3093<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3094
3095<table>
3096 <tr>
3097 <th>Analog Controls</strong><sup>1</sup></td>
3098 <th>HID Usage</th>
3099 <th>Android Button</th>
3100 </tr>
3101 <tr>
3102 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3103 <td>0x02 0x00C5</td>
3104 <td>AXIS_LTRIGGER </td>
3105 </tr>
3106 <tr>
3107 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3108 <td>0x02 0x00C4</td>
3109 <td>AXIS_RTRIGGER </td>
3110 </tr>
3111 <tr>
3112 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3113 <td>0x01 0x0030</p>
3114
3115<p>0x01 0x0031</td>
3116 <td>AXIS_X</p>
3117
3118<p>AXIS_Y</td>
3119 </tr>
3120 <tr>
3121 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3122 <td>0x01 0x0032</p>
3123
3124<p>0x01 0x0035</td>
3125 <td>AXIS_Z</p>
3126
3127<p>AXIS_RZ</td>
3128 </tr>
3129</table>
3130
3131
3132<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3133
3134<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3135
3136
3137<p>Android Television device implementations SHOULD provide a remote control to
3138allow users to access the TV interface. The remote control MAY be a physical
3139remote or can be a software-based remote that is accessible from a mobile phone
3140or tablet. The remote control MUST meet the requirements defined below.</p>
3141
3142<ul>
3143 <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>
3144 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3145support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3146</ul>
3147
3148<h2 id="7_3_sensors">7.3. Sensors</h2>
3149
3150
3151<p>Android includes APIs for accessing a variety of sensor types. Devices
3152implementations generally MAY omit these sensors, as provided for in the
3153following subsections. If a device includes a particular sensor type that has a
3154corresponding API for third-party developers, the device implementation MUST
3155implement that API as described in the Android SDK documentation and the
3156Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3157
3158<ul>
3159 <li>MUST accurately report the presence or absence of sensors per the
3160android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3161 <li>MUST return an accurate list of supported sensors via the
3162SensorManager.getSensorList() and similar methods.</li>
3163 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3164true or false as appropriate when applications attempt to register listeners,
3165not calling sensor listeners when the corresponding sensors are not present;
3166etc.).</li>
3167 <li>MUST report all sensor measurements using the relevant International System of
3168Units (metric) values for each sensor type as defined in the Android SDK
3169documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3170 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3171documentation, representing the time the event happened and synchronized with
3172the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3173are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3174platform releases where this might become a REQUIRED component. The
3175synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3176</ul>
3177
3178<p>The list above is not comprehensive; the documented behavior of the Android SDK
3179and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3180
3181<p>Some sensor types are composite, meaning they can be derived from data provided
3182by one or more other sensors. (Examples include the orientation sensor, and the
3183linear acceleration sensor.) Device implementations SHOULD implement these
3184sensor types, when they include the prerequisite physical sensors as described
3185in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3186If a device implementation includes a composite sensor it MUST implement the
3187sensor as described in the Android Open Source documentation on composite
3188sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3189
3190<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3191continuously [<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
3192sensor, device implementations MUST continuously provide periodic data samples
3193that SHOULD have a jitter below 3%, where jitter is defined as the standard
3194deviation of the difference of the reported timestamp values between
3195consecutive events.</p>
3196
3197<p>Note that the device implementations MUST ensure that the sensor event stream
3198MUST NOT prevent the device CPU from entering a suspend state or waking up from
3199a suspend state.</p>
3200
3201<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3202exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3203
3204<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3205
3206
3207<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3208devices and Android Watch devices are strongly encouraged to include this
3209sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3210
3211<ul>
3212 <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>
3213 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3214 Android Watch devices as such devices have a stricter power constraint and
3215 100 Hz for all other device types.</li>
3216 <li>SHOULD report events up to at least 200 Hz.</li>
3217 <li>MUST comply with the Android sensor coordinate system as detailed in the
3218Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3219 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3220more on any axis.</li>
3221 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3222least 16-bits.</li>
3223 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3224cycle and compensated, and preserve the compensation parameters between device
3225reboots.</li>
3226 <li>SHOULD be temperature compensated.</li>
3227 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3228deviation should be calculated on a per axis basis on samples collected over a
3229period of at least 3 seconds at the fastest sampling rate.</li>
3230 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3231TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3232Android 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
3233sensors are implemented, the sum of their power consumption MUST always be less
3234than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3235dynamic or static condition.</li>
3236 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3237TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3238TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3239are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3240 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3241and a magnetometer sensor is also included.</li>
3242</ul>
3243
3244<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3245
3246
3247<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3248device does include a 3-axis magnetometer, it:</p>
3249
3250<ul>
3251 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3252TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3253strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3254 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3255report events up to at least 50 Hz.</li>
3256 <li>MUST comply with the Android sensor coordinate system as detailed in the
3257Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3258 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3259saturating.</li>
3260 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3261below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3262and static (magnet-induced) magnetic fields.</li>
3263 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3264equal or denser than 0.2 &micro;.</li>
3265 <li>SHOULD be temperature compensated.</li>
3266 <li>MUST support online calibration and compensation of the hard iron bias, and
3267preserve the compensation parameters between device reboots.</li>
3268 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3269while in use or during the production of the device.</li>
3270 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3271collected over a period of at least 3 seconds at the fastest sampling rate, no
3272greater than 0.5 &micro;T.</li>
3273 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3274sensor and a gyroscope sensor is also included.</li>
3275 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3276sensor is also implemented. However if implemented, it MUST consume less than
327710 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3278mode at 10 Hz.</li>
3279</ul>
3280
3281<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3282
3283
3284<p>Device implementations SHOULD include a GPS receiver. If a device
3285implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3286
3287<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3288
3289
3290<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3291Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3292also included. If a device implementation includes a gyroscope, it:</p>
3293
3294<ul>
3295 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3296TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3297strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3298 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3299 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3300 Android Watch devices as such devices have a stricter power constraint and
3301 100 Hz for all other device types.</li>
3302 <li>SHOULD report events up to at least 200 Hz.</li>
3303 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
330416-bits or more.</li>
3305 <li>MUST be temperature compensated.</li>
3306 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3307parameters between device reboots.</li>
3308 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3309or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3310be constrained by this value. In other words, if you measure the variance of
3311the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3312 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3313sensor and a magnetometer sensor is also included.</li>
3314 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3315TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3316TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3317are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3318</ul>
3319
3320<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3321
3322
3323<p>Device implementations SHOULD include a barometer (ambient air pressure
3324sensor). If a device implementation includes a barometer, it:</p>
3325
3326<ul>
3327 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3328 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3329 <li>MUST have adequate precision to enable estimating altitude.</li>
3330 <li>MUST be temperature compensated.</li>
3331</ul>
3332
3333<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3334
3335
3336<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3337If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3338measure the ambient (room) temperature in degrees Celsius.</p>
3339
3340<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3341present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3342temperature of the device CPU, and it MUST NOT measure any other temperature.
3343Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3344
3345<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3346
3347
3348<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3349
3350<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3351
3352
3353<p>Device implementations MAY include a proximity sensor. Devices that can make a
3354voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3355SHOULD include a proximity sensor. If a device implementation does include a
3356proximity sensor, it:</p>
3357
3358<ul>
3359 <li>MUST measure the proximity of an object in the same direction as the screen.
3360That is, the proximity sensor MUST be oriented to detect objects close to the
3361screen, as the primary intent of this sensor type is to detect a phone in use
3362by the user. If a device implementation includes a proximity sensor with any
3363other orientation, it MUST NOT be accessible through this API.</li>
3364 <li>MUST have 1-bit of accuracy or more.</li>
3365</ul>
3366
3367<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3368
3369
3370<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3371
3372
3373<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3374to hardware related to placing voice calls and sending SMS messages via a GSM
3375or CDMA network. While these voice calls may or may not be packet-switched,
3376they are for the purposes of Android considered independent of any data
3377connectivity that may be implemented using the same network. In other words,
3378the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3379calls and SMS. For instance, device implementations that cannot place calls or
3380send/receive SMS messages MUST NOT report the android.hardware.telephony
3381feature or any subfeatures, regardless of whether they use a cellular network
3382for data connectivity.</p>
3383
3384<p>Android MAY be used on devices that do not include telephony hardware. That is,
3385Android is compatible with devices that are not phones. However, if a device
3386implementation does include GSM or CDMA telephony, it MUST implement full
3387support for the API for that technology. Device implementations that do not
3388include telephony hardware MUST implement the full APIs as no-ops.</p>
3389
3390<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3391
3392<div class="note">
3393<p>Android Television device implementations MUST include Wi-Fi support.</p>
3394</div>
3395
3396
3397<p>Android Television device implementations MUST include support for one or more
3398forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3399implementation SHOULD include support for one or more forms of 802.11. If a
3400device implementation does include support for 802.11 and exposes the
3401functionality to a third-party application, it MUST implement the corresponding
3402Android API and:</p>
3403
3404<ul>
3405 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3406 <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>
3407 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3408(224.0.0.251) at any time of operation including when the screen is not in an
3409active state.</li>
3410</ul>
3411
3412<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3413
3414
3415<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3416peer-to-peer). If a device implementation does include support for Wi-Fi
3417Direct, it MUST implement the corresponding Android API as described in the SDK
3418documentation [<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>
3419
3420<ul>
3421 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3422 <li>MUST support regular Wi-Fi operation.</li>
3423 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3424</ul>
3425
3426<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3427
3428<div class="note">
3429<p>Android Television device implementations MUST include support for Wi-Fi
3430Tunneled Direct Link Setup (TDLS).</p>
3431</div>
3432
3433
3434<p>Android Television device implementations MUST include support for Wi-Fi
3435Tunneled Direct Link Setup (TDLS) and other types of Android device
3436implementations SHOULD include support for Wi-Fi TDLS as described in the
3437Android 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
3438by the WiFiManager API, the device:</p>
3439
3440<ul>
3441 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3442 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3443than going through the Wi-Fi access point.</li>
3444</ul>
3445
3446<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3447
3448<div class="note">
3449<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3450Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3451</div>
3452
3453
3454<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
3455Energy MUST declare the relevant platform features (android.hardware.bluetooth
3456and android.hardware.bluetooth_le respectively) and implement the platform
3457APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3458as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3459device implementations MUST support Bluetooth and Bluetooth LE. </p>
3460
3461<p>Device implementations including support for Bluetooth Low Energy:</p>
3462
3463<ul>
3464 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3465 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3466described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3467 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3468implementing 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
3469android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3470 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3471if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3472android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3473 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3474MUST report &lsquo;false&rsquo; whenever queried via the
3475android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3476</ul>
3477
3478<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3479
3480
3481<p>Device implementations SHOULD include a transceiver and related hardware for
3482Near-Field Communications (NFC). If a device implementation does include NFC
3483hardware and plans to make it available to third-party apps, then it:</p>
3484
3485<ul>
3486 <li>MUST report the android.hardware.nfc feature from the
3487android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3488 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3489standards:
3490 <ul>
3491 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3492Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3493following NFC standards:
3494 <ul>
3495 <li>NfcA (ISO14443-3A)</li>
3496 <li>NfcB (ISO14443-3B)</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3497 <li>NfcF (JIS X 6319-4)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3498 <li>IsoDep (ISO 14443-4)</li>
3499 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3500 </ul>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3501 <li>MUST be capable of reading and writing NDEF messages as well as raw
3502 data via the following NFC standards:</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3503 <ul>
3504 <li>NfcV (ISO 15693)</li>
3505 </ul></li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3506 <li>SHOULD be capable of reading the barcode and URL (if encoded) of
3507 Thinfilm NFC Barcode
3508 [<a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">Resources, XX</a>] products.
3509 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3510 <li>MUST be capable of transmitting and receiving data via the following
3511peer-to-peer standards and protocols:
3512 <ul>
3513 <li>ISO 18092</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3514 <li>LLCP 1.2 (defined by the NFC Forum)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3515 <li>SDP 1.0 (defined by the NFC Forum)</li>
3516 <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>
3517 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3518 </ul></li>
3519 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3520 <ul>
3521 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3522default SNEP server MUST be dispatched to applications using the
3523android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3524MUST NOT disable dispatch of incoming NDEF message.</li>
3525 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3526settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3527 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3528processed the same way as the SNEP default server.</li>
3529 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3530default SNEP server when Android Beam is enabled. If no default SNEP server is
3531found then the client MUST attempt to send to an NPP server.</li>
3532 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3533android.nfc.NfcAdapter.setNdefPushMessage, and
3534android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3535android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3536 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3537sending outbound P2P NDEF messages.</li>
3538 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3539using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3540 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3541Bluetooth Object Push Profile. Device implementations MUST support connection
3542handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3543implementing 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
3544LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3545handover request/select records over NFC, and it MUST use the Bluetooth Object
3546Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3547remain compatible with Android 4.1 devices), the implementation SHOULD still
3548accept SNEP GET requests for exchanging the handover request/select records
3549over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3550for performing connection handover.</li>
3551 </ul></li>
3552 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3553 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3554active and the lock-screen unlocked.</li>
3555</ul>
3556</ul>
3557
3558<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3559Forum specifications cited above.)</p>
3560
3561<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3562device implementation does include an NFC controller chipset capable of HCE and
3563Application ID (AID) routing, then it:</p>
3564
3565<ul>
3566 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3567 <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>
3568</ul>
3569
3570<p>Additionally, device implementations MAY include reader/writer support for the
3571following MIFARE technologies.</p>
3572
3573<ul>
3574 <li>MIFARE Classic</li>
3575 <li>MIFARE Ultralight</li>
3576 <li>NDEF on MIFARE Classic</li>
3577</ul>
3578
3579<p>Note that Android includes APIs for these MIFARE types. If a device
3580implementation supports MIFARE in the reader/writer role, it:</p>
3581
3582<ul>
3583 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3584 <li>MUST report the feature com.nxp.mifare from the
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3585android.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
3586as a constant in the android.content.pm.PackageManager class.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3587 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3588feature unless it also implements general NFC support as described in this
3589section.</li>
3590</ul>
3591
3592<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3593the android.hardware.nfc feature from the
3594android.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>
3595
3596<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3597protocol-independent data representation format, device implementations MUST
3598implement these APIs even if they do not include support for NFC or declare the
3599android.hardware.nfc feature.</p>
3600
3601<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3602
3603
3604<p>Device implementations MUST include support for one or more forms of data
3605networking. Specifically, device implementations MUST include support for at
3606least one data standard capable of 200Kbit/sec or greater. Examples of
3607technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3608Ethernet, Bluetooth PAN, etc.</p>
3609
3610<p>Device implementations where a physical networking standard (such as Ethernet)
3611is the primary data connection SHOULD also include support for at least one
3612common wireless data standard, such as 802.11 (Wi-Fi).</p>
3613
3614<p>Devices MAY implement more than one form of data connectivity.</p>
3615
3616<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3617
3618
3619<p>Device implementations MUST have the master auto-sync setting on by default so
3620that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3621
3622<h2 id="7_5_cameras">7.5. Cameras</h2>
3623
3624
3625<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3626front-facing camera. A rear-facing camera is a camera located on the side of
3627the device opposite the display; that is, it images scenes on the far side of
3628the device, like a traditional camera. A front-facing camera is a camera
3629located on the same side of the device as the display; that is, a camera
3630typically used to image the user, such as for video conferencing and similar
3631applications.</p>
3632
3633<p>If a device implementation includes at least one camera, it SHOULD be possible
3634for an application to simultaneously allocate 3 bitmaps equal to the size of
3635the images produced by the largest-resolution camera sensor on the device.</p>
3636
3637<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3638
3639
3640<p>Device implementations SHOULD include a rear-facing camera. If a device
3641implementation includes at least one rear-facing camera, it:</p>
3642
3643<ul>
3644 <li>MUST report the feature flag android.hardware.camera and
3645android.hardware.camera.any.</li>
3646 <li>MUST have a resolution of at least 2 megapixels.</li>
3647 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3648the camera driver (transparent to application software).</li>
3649 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3650 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3651lit while an android.hardware.Camera.PreviewCallback instance has been
3652registered on a Camera preview surface, unless the application has explicitly
3653enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3654of a Camera.Parameters object. Note that this constraint does not apply to the
3655device&rsquo;s built-in system camera application, but only to third-party
3656applications using Camera.PreviewCallback.</li>
3657</ul>
3658
3659<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3660
3661
3662<p>Device implementations MAY include a front-facing camera. If a device
3663implementation includes at least one front-facing camera, it:</p>
3664
3665<ul>
3666 <li>MUST report the feature flag android.hardware.camera.any and
3667android.hardware.camera.front.</li>
3668 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3669 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3670camera API in Android has specific support for front-facing cameras and device
3671implementations MUST NOT configure the API to to treat a front-facing camera as
3672the default rear-facing camera, even if it is the only camera on the device.</li>
3673 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3674cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3675 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3676CameraPreview, as follows:
3677 <ul>
3678 <li>If the device implementation is capable of being rotated by user (such as
3679automatically via an accelerometer or manually via user input), the camera
3680preview MUST be mirrored horizontally relative to the device&rsquo;s current
3681orientation.</li>
3682 <li>If the current application has explicitly requested that the Camera display be
3683rotated 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
3684orientation specified by the application.</li>
3685 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3686axis.</li>
3687 </ul></li>
3688 <li>MUST mirror the image displayed by the postview in the same manner as the
3689camera preview image stream. If the device implementation does not support
3690postview, this requirement obviously does not apply.</li>
3691 <li>MUST NOT mirror the final captured still image or video streams returned to
3692application callbacks or committed to media storage.</li>
3693</ul>
3694
3695<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3696
3697
3698<p>Device implementations with USB host mode MAY include support for an external
3699camera that connects to the USB port. If a device includes support for an
3700external camera, it:</p>
3701
3702<ul>
3703 <li>MUST declare the platform feature android.hardware.camera.external and
3704android.hardware camera.any.</li>
3705 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3706 <li>MAY support multiple cameras.</li>
3707</ul>
3708
3709<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3710high-quality unencoded streams (i.e. raw or independently compressed picture
3711streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3712unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3713device implementation.</p>
3714
3715<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3716
3717
3718<p>Android includes two API packages to access the camera, the newer
3719android.hardware.camera2 API expose lower-level camera control to the app,
3720including efficient zero-copy burst/streaming flows and per-frame controls of
3721exposure, gain, white balance gains, color conversion, denoising, sharpening,
3722and more.</p>
3723
3724<p>The older API package, android.hardware.Camera, is marked as deprecated in
3725Android 5.0 but as it should still be available for apps to use Android device
3726implementations MUST ensure the continued support of the API as described in
3727this section and in the Android SDK.</p>
3728
3729<p>Device implementations MUST implement the following behaviors for the
3730camera-related APIs, for all available cameras:</p>
3731
3732<ul>
3733 <li>If an application has never called
3734android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3735use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3736application callbacks.</li>
3737 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3738and the system calls the onPreviewFrame() method when the preview format is
3739YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3740be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3741 <li>For android.hardware.Camera, device implementations MUST support the YV12
3742format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3743camera previews for both front- and rear-facing cameras. (The hardware video
3744encoder and camera may use any native pixel format, but the device
3745implementation MUST support conversion to YV12.)</li>
3746 <li>For android.hardware.camera2, device implementations must support the
3747android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3748formats as outputs through the android.media.ImageReader API.</li>
3749</ul>
3750
3751<p>Device implementations MUST still implement the full Camera API included in the
3752Android 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
3753capabilities. For instance, cameras that lack autofocus MUST still call any
3754registered android.hardware.Camera.AutoFocusCallback instances (even though
3755this has no relevance to a non-autofocus camera.) Note that this does apply to
3756front-facing cameras; for instance, even though most front-facing cameras do
3757not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3758
3759<p>Device implementations MUST recognize and honor each parameter name defined as
3760a constant on the android.hardware.Camera.Parameters class, if the underlying
3761hardware supports the feature. If the device hardware does not support a
3762feature, the API must behave as documented. Conversely, device implementations
3763MUST NOT honor or recognize string constants passed to the
3764android.hardware.Camera.setParameters() method other than those documented as
3765constants on the android.hardware.Camera.Parameters. That is, device
3766implementations MUST support all standard Camera parameters if the hardware
3767allows, and MUST NOT support custom Camera parameter types. For instance,
3768device implementations that support image capture using high dynamic range
3769(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>
3770
3771<p>Because not all device implementations can fully support all the features of
3772the android.hardware.camera2 API, device implementations MUST report the proper
3773level of support with the android.info.supportedHardwareLevel property as
3774described 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>
3775
3776<p>Device implementations MUST also declare its Individual camera capabilities of
3777android.hardware.camera2 via the android.request.availableCapabilities property
3778and 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>
3779
3780<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3781whenever a new picture is taken by the camera and the entry of the picture has
3782been added to the media store.</p>
3783
3784<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3785whenever a new video is recorded by the camera and the entry of the picture has
3786been added to the media store.</p>
3787
3788<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3789
3790
3791<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3792long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3793when the device is held in the landscape orientation, cameras MUST capture
3794images in the landscape orientation. This applies regardless of the device&rsquo;s
3795natural orientation; that is, it applies to landscape-primary devices as well
3796as portrait-primary devices.</p>
3797
3798<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3799
3800
3801<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3802
3803<div class="note">
3804<p>Android Television devices MUST have at least 5GB of non-volatile storage
3805available for application private data.</p>
3806</div>
3807
3808
3809<p>The memory available to the kernel and userspace on device implementations MUST
3810be at least equal or larger than the minimum values specified by the following
3811table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3812<table>
3813 <tr>
3814 <th>Density and screen size</th>
3815 <th>32-bit device</th>
3816 <th>64-bit device</th>
3817 </tr>
3818 <tr>
3819 <td>Android Watch devices (due to smaller screens)</td>
3820 <td>416MB</td>
3821 <td>Not applicable</td>
3822 </tr>
3823 <tr>
3824 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3825 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3826 <li class="table_list">mdpi or lower on large screens</li>
3827 <li class="table_list">ldpi or lower on extra large screens</li>
3828 </ul></td>
3829 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3830 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3831 </tr>
3832 <tr>
3833 <td><ul>
3834 <li class="table_list">xhdpi or higher on small/normal screens</li>
3835 <li class="table_list">hdpi or higher on large screens</li>
3836 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3837 <td>512MB</td>
3838 <td>832MB</td>
3839 </tr>
3840 <tr>
3841 <td><ul>
3842 <li class="table_list">400dpi or higher on small/normal screens</li>
3843 <li class="table_list">xhdpi or higher on large screens</li>
3844 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3845 <td>896MB</td>
3846 <td>1280MB</td>
3847 </tr>
3848 <tr>
3849 <td><ul>
3850 <li class="table_list">560dpi or higher on small/normal screens</li>
3851 <li class="table_list">400dpi or higher on large screens</li>
3852 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3853 <td>1344MB</td>
3854 <td>1824MB</td>
3855 </tr>
3856</table>
3857
3858
3859<p>The minimum memory values MUST be in addition to any memory space already
3860dedicated to hardware components such as radio, video, and so on that is not
3861under the kernel&rsquo;s control.</p>
3862
3863<p>Device implementations with less than 512MB of memory available to the kernel
3864and userspace, unless an Android Watch, MUST return the value "true" for
3865ActivityManager.isLowRamDevice().</p>
3866
3867<p>Android Television devices MUST have at least 5GB and other device
3868implementations MUST have at least 1.5GB of non-volatile storage available for
3869application private data. That is, the /data partition MUST be at least 5GB for
3870Android Television devices and at least 1.5GB for other device implementations.
3871Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3872they will be able to upgrade to the future platform releases.</p>
3873
3874<p>The Android APIs include a Download Manager that applications MAY use to
3875download 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
3876downloading individual files of at least 100MB in size to the default &ldquo;cache"
3877location.</p>
3878
3879<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3880
3881
3882<p>Device implementations MUST offer shared storage for applications also often
3883referred as &ldquo;shared external storage&rdquo;. </p>
3884
3885<p>Device implementations MUST be configured with shared storage mounted by
3886default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3887path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3888to the actual mount point.</p>
3889
3890<p>Device implementations MAY have hardware for user-accessible removable storage,
3891such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3892shared storage requirement, the device implementation:</p>
3893
3894<ul>
3895 <li>MUST implement a toast or pop-up user interface warning the user when there is
3896no SD card.</li>
3897 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3898and other material available at time of purchase that the SD card has to be
3899separately purchased.</li>
3900 <li>MUST mount the SD card by default.</li>
3901</ul>
3902
3903<p>Alternatively, device implementations MAY allocate internal (non-removable)
3904storage as shared storage for apps as included in the upstream Android Open
3905Source Project; device implementations SHOULD use this configuration and
3906software implementation. If a device implementation uses internal
3907(non-removable) storage to satisfy the shared storage requirement, that storage
3908MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3909symbolic link to the physical location if it is mounted elsewhere).</p>
3910
3911<p>Device implementations MUST enforce as documented the
3912android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3913Shared storage MUST otherwise be writable by any application that obtains that
3914permission.</p>
3915
3916<p>Device implementations that include multiple shared storage paths (such as both
3917an SD card slot and shared internal storage) MUST NOT allow Android
3918applications to write to the secondary external storage, except for their
3919package-specific directories on the secondary external storage, but SHOULD
3920expose content from both storage paths transparently through Android&rsquo;s media
3921scanner service and android.provider.MediaStore.</p>
3922
3923<p>Regardless of the form of shared storage used, if the device implementation
3924has a USB port with USB peripheral mode support, it MUST provide some mechanism
3925to access the contents of shared storage from a host computer. Device
3926implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3927to satisfy this requirement. If the device implementation supports Media
3928Transfer Protocol, it:</p>
3929
3930<ul>
3931 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3932[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3933 <li>SHOULD report a USB device class of 0x00.</li>
3934 <li>SHOULD report a USB interface name of 'MTP'.</li>
3935</ul>
3936
3937<h2 id="7_7_usb">7.7. USB</h2>
3938
3939
3940<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3941USB host mode.</p>
3942
3943<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3944
3945<ul>
3946 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3947-C USB port.</li>
3948 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3949new 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>
3950 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3951SHOULD either locate the port on the bottom of the device (according to natural
3952orientation) or enable software screen rotation for all apps (including home
3953screen), so that the display draws correctly when the device is oriented with
3954the 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>
3955 <li>It MUST allow a USB host connected with the Android device to access the
3956contents of the shared storage volume using either USB mass storage or Media
3957Transfer Protocol.</li>
3958 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3959documented in the Android SDK documentation, and if it is an Android Handheld
3960device it MUST implement the AOA API. Device implementations implementing the
3961AOA specification:
3962 <ul>
3963 <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>
3964 <li>MUST implement the USB audio class as documented in the Android SDK
3965documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3966 </ul></li>
3967 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3968as 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>
3969 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3970the value of android.os.Build.SERIAL.</li>
3971</ul>
3972
3973<p>If a device implementation includes a USB port supporting host mode, it:</p>
3974
3975<ul>
3976 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3977 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3978cables adapting the port to a standard type-A or type-C USB port.</li>
3979 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3980adapting the port to a standard type-A or type-C USB port.</li>
3981 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3982documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3983 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3984MUST 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>
3985 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3986as 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>
3987</ul>
3988
3989<h2 id="7_8_audio">7.8. Audio</h2>
3990
3991
3992<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3993
3994<div class="note">
3995<p>Android Handheld, Watch, and Automotive implementations MUST include a
3996microphone.</p>
3997</div>
3998
3999
4000<p>Device implementations MAY omit a microphone. However, if a device
4001implementation omits a microphone, it MUST NOT report the
4002android.hardware.microphone feature constant, and MUST implement the audio
4003recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4004
4005<ul>
4006 <li>MUST report the android.hardware.microphone feature constant
4007 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
4008 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
4009</ul>
4010
4011<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4012
4013<div class="note">
4014<p>Android Watch devices MAY include an audio output.</p>
4015</div>
4016
4017<p>Device implementations including a speaker or with an audio/multimedia output
4018port for an audio output peripheral as a headset or an external speaker:</p>
4019
4020<ul>
4021 <li>MUST report the android.hardware.audio.output feature constant.</li>
4022 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4023 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4024</ul>
4025
4026<p>Conversely, if a device implementation does not include a speaker or audio
4027output port, it MUST NOT report the android.hardware.audio output feature, and
4028MUST implement the Audio Output related APIs as no-ops at least. </p>
4029
4030<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4031other types of Android device implementations MUST have an audio output and
4032declare android.hardware.audio.output.</p>
4033
4034<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4035
4036
4037<p>In order to be compatible with the headsets and other audio accessories using
4038the 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
4039one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4040implementation has a 4 conductor 3.5mm audio jack, it:</p>
4041
4042<ul>
4043 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4044microphone, and SHOULD support audio recording from stereo headsets with a
4045microphone.</li>
4046 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4047audio plugs with the OMTP pin-out order.</li>
4048 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4049the device implementation supports a microphone, and broadcast the
4050android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4051 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4052ranges of equivalent impedance between the microphone and ground conductors on
4053the audio plug:
4054 <ul>
4055 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4056 <li><strong>210&#45;290 Ohm</strong>: KEYCODE_VOLUME_UP</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4057 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4058 </ul></li>
4059 <li>SHOULD support the detection and mapping to the keycode for the following range
4060of equivalent impedance between the microphone and ground conductors on the
4061audio plug:
4062 <ul>
4063 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4064 </ul></li>
4065 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4066contacts on plug are touching their relevant segments on the jack.</li>
4067 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4068speaker impedance.</li>
4069 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4070</ul>
4071
4072<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4073
4074
4075<p>Some minimum performance criterias are critical to the user experience and
4076impacts the baseline assumptions developers would have when developing an app.
4077Android Watch devices SHOULD and other type of device implementations MUST meet
4078the following criteria:</p>
4079
4080<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4081
4082
4083<p>Device implementations MUST provide a smooth user interface by ensuring a
4084consistent frame rate and response times for applications and games. Device
4085implementations MUST meet the following requirements: </p>
4086
4087<ul>
4088 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4089often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4090 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4091list of 10K list entries as defined by the Android Compatibility Test Suite
4092(CTS) in less than 36 secs.</li>
4093 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4094application after it has been launched MUST take less than 1 second.</li>
4095</ul>
4096
4097<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4098
4099
4100<p>Device implementations MUST ensure internal storage file access performance consistency for read
4101and write operations. </p>
4102
4103<ul>
4104 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4105for a 256MB file using 10MB write buffer.</li>
4106 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4107256MB file using 4KB write buffer.</li>
4108 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4109a 256MB file using 10MB write buffer.</li>
4110 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4111256MB file using 4KB write buffer.</li>
4112</ul>
4113
4114<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4115
4116
4117<p>Device implementations MUST implement a security model consistent with the
4118Android platform security model as defined in Security and Permissions
4119reference 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
4120installation of self-signed applications without requiring any additional
4121permissions/certificates from any third parties/authorities. Specifically,
4122compatible devices MUST support the security mechanisms described in the follow
4123subsections.</p>
4124
4125<h2 id="9_1_permissions">9.1. Permissions</h2>
4126
4127
4128<p>Device implementations MUST support the Android permissions model as defined in
4129the 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
4130described in the SDK documentation; no permissions may be omitted, altered, or
4131ignored. Implementations MAY add additional permissions, provided the new
4132permission ID strings are not in the android.* namespace.</p>
4133
Svetoslav4bbf7402015-09-11 14:45:48 -0700[diff] [blame]4134<p>Permissions with a protection level of dangerous are runtime permissions. Applications
4135with targetSdkVersion > 22 request them at runtime. The system MUST show a dedicated UI for the
4136user to decide whether to grant the requested runtime permissions and also provide a UI for the
4137user to manage runtime permissions. On the system there MUST be one and only one
4138implementation of both the UI for the user to accept runtime permissions and the UI for
4139the user to manage runtime permissions.</p>
4140
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4141<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4142
4143
4144<p>Device implementations MUST support the Android application sandbox model, in
4145which each application runs as a unique Unixstyle UID and in a separate
4146process. Device implementations MUST support running multiple applications as
4147the same Linux user ID, provided that the applications are properly signed and
4148constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4149
4150<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4151
4152
4153<p>Device implementations MUST support the Android file access permissions model
4154as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4155
4156<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4157
4158
4159<p>Device implementations MAY include runtime environments that execute
4160applications using some other software or technology than the Dalvik Executable
4161Format or native code. However, such alternate execution environments MUST NOT
4162compromise the Android security model or the security of installed Android
4163applications, as described in this section.</p>
4164
4165<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4166standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4167
4168<p>Alternate runtimes MUST NOT be granted access to resources protected by
4169permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4170&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4171
4172<p>Alternate runtimes MUST NOT permit applications to make use of features
4173protected by Android permissions restricted to system applications.</p>
4174
4175<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4176alternate runtimes:</p>
4177
4178<ul>
4179 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4180Linux user IDs, etc.).</li>
4181 <li>MAY provide a single Android sandbox shared by all applications using the
4182alternate runtime.</li>
4183 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4184sandbox of any other app installed on the device, except through the standard
4185Android mechanisms of shared user ID and signing certificate.</li>
4186 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4187corresponding to other Android applications.</li>
4188 <li>MUST NOT be launched with, be granted, or grant to other applications any
4189privileges of the superuser (root), or of any other user ID.</li>
4190</ul>
4191
4192<p>The .apk files of alternate runtimes MAY be included in the system image of a
4193device implementation, but MUST be signed with a key distinct from the key used
4194to sign other applications included with the device implementation.</p>
4195
4196<p>When installing applications, alternate runtimes MUST obtain user consent for
4197the Android permissions used by the application. If an application needs to
4198make use of a device resource for which there is a corresponding Android
4199permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4200user that the application will be able to access that resource. If the runtime
4201environment does not record application capabilities in this manner, the
4202runtime environment MUST list all permissions held by the runtime itself when
4203installing any application using that runtime.</p>
4204
4205<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4206
4207<div class="note">
4208<p>This feature is optional for all device types.</p>
4209</div>
4210
4211
4212<p>Android includes support for multiple users and provides support for full user
4213isolation [<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
4214the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4215
4216<ul>
4217 <li>Device implementations that do not declare the android.hardware.telephony
4218feature flag MUST support restricted profiles, a feature that allows device
4219owners to manage additional users and their capabilities on the device. With
4220restricted profiles, device owners can quickly set up separate environments for
4221additional users to work in, with the ability to manage finer-grained
4222restrictions in the apps that are available in those environments.</li>
4223 <li>Conversely device implementations that declare the android.hardware.telephony
4224feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4225implementation of controls to enable /disable other users from accessing the
4226voice calls and SMS.</li>
4227 <li>Device implementations MUST, for each user, implement a security model
4228consistent with the Android platform security model as defined in Security and
4229Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4230 <li>Device implementations MAY support creating users and managed profiles via the
4231android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4232platform feature flag android.software.managed_users.
4233 <li>Device implementations that declare the feature flag
4234android.software.managed_users MUST use the upstream AOSP icon badge to
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4235represent the managed applications and other badge UI elements like Recents &amp;
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4236Notifications.</li>
4237 <li>Each user instance on an Android device MUST have separate and isolated
4238external storage directories. Device implementations MAY store multiple users'
4239data on the same volume or filesystem. However, the device implementation MUST
4240ensure that applications owned by and running on behalf a given user cannot
4241list, read, or write to data owned by any other user. Note that removable
4242media, such as SD card slots, can allow one user to access another&rsquo;s data by
4243means of a host PC. For this reason, device implementations that use removable
4244media for the external storage APIs MUST encrypt the contents of the SD card if
4245multiuser is enabled using a key stored only on non-removable media accessible
4246only to the system. As this will make the media unreadable by a host PC, device
4247implementations will be required to switch to MTP or a similar system to
4248provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4249implementations MAY but SHOULD NOT enable multi-user if they use removable
4250media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4251</ul>
4252
4253<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4254
4255
4256<p>Android includes support for warning users of any outgoing premium SMS message
4257[<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
4258carrier that may incur a charge to the user. Device implementations that
4259declare support for android.hardware.telephony MUST warn users before sending a
4260SMS message to numbers identified by regular expressions defined in
4261/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4262Project provides an implementation that satisfies this requirement.</p>
4263
4264<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4265
4266
4267<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4268(SELinux) mandatory access control (MAC) system and other security features in
4269the Linux kernel. SELinux or any other security features, if implemented below
4270the Android framework:</p>
4271
4272<ul>
4273 <li>MUST maintain compatibility with existing applications.</li>
4274 <li>MUST NOT have a visible user interface when a security violation is detected
4275and successfully blocked, but MAY have a visible user interface when an
4276unblocked security violation occurs resulting in a successful exploit.</li>
4277 <li>SHOULD NOT be user or developer configurable.</li>
4278</ul>
4279
4280<p>If any API for configuration of policy is exposed to an application that can
4281affect another application (such as a Device Administration API), the API MUST
4282NOT allow configurations that break compatibility.</p>
4283
4284<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4285if using a kernel other than Linux and meet the following requirements, which
4286are satisfied by the reference implementation in the upstream Android Open
4287Source Project.</p>
4288
4289<p>Device implementations:</p>
4290
4291<ul>
4292 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4293per-domain basis, and MUST configure all domains in enforcing mode. No
4294permissive mode domains are allowed, including domains specific to a
4295device/vendor.</li>
4296 <li>SHOULD load policy from /sepolicy file on the device.</li>
4297 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4298sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4299the policy MUST compile with all neverallow present, for both AOSP SELinux
4300domains as well as device/vendor specific domains.</li>
4301 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4302system image update.</li>
4303</ul>
4304
4305<p>Device implementations SHOULD retain the default SELinux policy provided in the
4306upstream Android Open Source Project, until they have first audited their
4307additions to the SELinux policy. Device implementations MUST be compatible with
4308the upstream Android Open Source Project.</p>
4309
4310<h2 id="9_8_privacy">9.8. Privacy</h2>
4311
4312<p>If the device implements functionality in the system that captures the contents
4313displayed on the screen and/or records the audio stream played on the device,
4314it MUST continuously notify the user whenever this functionality is enabled and
4315actively capturing/recording.</p>
4316
4317<p>If a device implementation has a mechanism that routes network data traffic
4318through a proxy server or VPN gateway by default (for example, preloading a VPN
4319service with android.permission.CONTROL_VPN granted), the device implementation
4320MUST ask for the user's consent before enabling that mechanism.</p>
4321
4322<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4323
4324<div class="note">
4325<p>Optional for Android device implementations without a lock screen.</p>
4326</div>
4327
4328
4329<p>If the device implementation supports a lock screen with PIN (numeric) or
4330PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4331application private data (/data partition), as well
4332as the SD card partition if it is a permanent, non-removable part of the device
4333[<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
4334be enabled all the time after the user has completed the out-of-box experience.
4335While this requirement is stated as SHOULD for this version of the Android
4336platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4337Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4338for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4339be written to storage at any time without being encrypted. Other than when in
4340active use, the encryption key SHOULD be AES encrypted with the lockscreen
4341passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4342If the user has not specified a lockscreen passcode or has disabled use of the
4343passcode for encryption, the system SHOULD use a default passcode to wrap the
4344encryption key. If the device provides a hardware-backed keystore, the password
4345stretching algorithm MUST be cryptographically bound to that keystore. The
4346encryption key MUST NOT be sent off the device (even when wrapped with the user
4347passcode and/or hardware bound key). The upstream Android Open Source project
4348provides a preferred implementation of this feature based on the linux kernel
4349feature dm-crypt.</p>
4350
4351<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4352
4353<p>
4354Verified boot is a feature that guarantees the integrity of the device software.
4355If a device implementation supports the feature, it MUST:
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4356</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4357<ul>
4358<li>Declare the platform feature flag android.software.verified_boot</li>
4359<li>Perform verification on every boot sequence</li>
4360<li>Start verification from a hardware key that is the root of trust, and go
4361all the way up to the system partition</li>
4362<li>Implement each stage of verification to check the integrity and authenticity
4363of all the bytes in the next stage before executing the code in the next stage</li>
4364<li>Use verification algorithms as strong as current recommendations
4365from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4366</ul>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4367
4368<p>Device implementations SHOULD support verified boot for device integrity.
4369While this requirement is SHOULD for this version of the Android platform,
4370it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4371in future versions of Android. The upstream Android Open Source Project provides
4372a preferred implementation of this feature based on the linux kernel feature dm-verity.
4373</p>
4374
4375<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4376
4377
4378<p>Device implementations MUST pass all tests described in this section.</p>
4379
4380<p>However, note that no software test package is fully comprehensive. For this
4381reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4382preferred implementation of Android available from the Android Open Source
4383Project. This will minimize the risk of introducing bugs that create
4384incompatibilities requiring rework and potential device updates.</p>
4385
4386<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4387
4388
4389<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
4390software on the device. Additionally, device implementers SHOULD use the
4391reference implementation in the Android Open Source tree as much as possible,
4392and MUST ensure compatibility in cases of ambiguity in CTS and for any
4393reimplementations of parts of the reference source code.</p>
4394
4395<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4396may itself contain bugs. The CTS will be versioned independently of this
4397Compatibility Definition, and multiple revisions of the CTS may be released for
4398Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4399at the time the device software is completed.</p>
4400
4401<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4402
4403
4404<p>Device implementations MUST correctly execute all applicable cases in the CTS
4405Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4406is intended to be run by a human operator to test functionality that cannot be
4407tested by an automated system, such as correct functioning of a camera and
4408sensors.</p>
4409
4410<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4411that is optional. Device implementations MUST pass all tests for hardware that
4412they possess; for instance, if a device possesses an accelerometer, it MUST
4413correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4414for features noted as optional by this Compatibility Definition Document MAY be
4415skipped or omitted.</p>
4416
4417<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4418above. However, since many builds are very similar, device implementers are not
4419expected to explicitly run the CTS Verifier on builds that differ only in
4420trivial ways. Specifically, device implementations that differ from an
4421implementation that has passed the CTS Verifier only by the set of included
4422locales, branding, etc. MAY omit the CTS Verifier test.</p>
4423
4424<h1 id="11_updatable_software">11. Updatable Software</h1>
4425
4426
4427<p>Device implementations MUST include a mechanism to replace the entirety of the
4428system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4429device restart MAY be required.</p>
4430
4431<p>Any method can be used, provided that it can replace the entirety of the
4432software preinstalled on the device. For instance, any of the following
4433approaches will satisfy this requirement:</p>
4434
4435<ul>
4436 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4437 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4438 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4439</ul>
4440
4441<p>However, if the device implementation includes support for an unmetered data
4442connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4443
4444<ul>
4445<li>Android Automotive implementations SHOULD support OTA downloads with offline
4446update via reboot.</li>
4447<li>All other device implementations MUST support OTA downloads with offline
4448update via reboot.</li>
4449</ul>
4450
4451<p>The update mechanism used MUST support updates without wiping user data. That
4452is, the update mechanism MUST preserve application private data and application
4453shared data. Note that the upstream Android software includes an update
4454mechanism that satisfies this requirement.</p>
4455
4456<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4457update mechanism SHOULD support verifying that the system image is binary
4458identical to expected result following an OTA. The block-based OTA
4459implementation in the upstream Android Open Source Project, added since Android
44605.1, satisfies this requirement.</p>
4461
4462<p>If an error is found in a device implementation after it has been released but
4463within its reasonable product lifetime that is determined in consultation with
4464the Android Compatibility Team to affect the compatibility of third-party
4465applications, the device implementer MUST correct the error via a software
4466update available that can be applied per the mechanism just described.</p>
4467
4468<h1 id="12_document_changelog">12. Document Changelog</h1>
4469
4470
4471<p>The following table contains a summary of the changes to the Compatibility
4472Definition in this release. </p>
4473<table>
4474 <tr>
4475 <th>Section</th>
4476 <th>Summary of change</th>
4477 </tr>
4478 <tr>
4479 <td>2. Device Types</td>
4480 <td>Added definition for Android automotive implementation.</td>
4481 </tr>
4482 <tr>
4483 <td>2.1 Device Configurations</td>
4484 <td>Added column for Android automotive implementation.</td>
4485 </tr>
4486 <tr>
4487 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4488 <td>New section added.</td>
4489 </tr>
4490 <tr>
4491 <td>3.4.1. WebView Compatibility</td>
4492 <td>Updated webview user agent string requirement to accomodate upstream
4493 implementation change.</td>
4494 </tr>
4495 <tr>
4496 <td>3.4.2. Browser compatibility</td>
4497 <td>Added Android automotive implementations as another case that MAY omit a
4498 browser application.</td>
4499 </tr>
4500 <tr>
4501 <td>3.7. Runtime Compatibility</td>
4502 <td>Updated required runtime heap size for smaller screens and added requirement
4503 for the new dpi bucket (280dpi).</td>
4504 </tr>
4505 <tr>
4506 <td>3.8.3. Notifications</td>
4507 <td>Clarified notification requirement for Android Watch, Television and
4508 Automotive implementations.</td>
4509 </tr>
4510 <tr>
4511 <td>3.8.10. Lock Screen Media Control<</td>
4512 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4513 </tr>
4514 <tr>
4515 <td>3.8.13. Unicode and font</td>
4516 <td>Relaxed Emoji character input method requirement.</td>
4517 </tr>
4518 <tr>
4519 <td>3.9. Device Administration</td>
4520 <td>Clarified condition when the full range of device administration policies
4521 has to be supported.</td>
4522 </tr>
4523 <tr>
4524 <td>3.10. Accessibility</td>
4525 <td>Added Android automotive requirements.</td>
4526 </tr>
4527 <tr>
4528 <td>3.11. Text-To-Speech</td>
4529 <td>Added Android automotive requirements.</td>
4530 </tr>
4531 <tr>
4532 <td>5.1. Media Codecs</td>
4533 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4534 </tr>
4535 <tr>
4536 <td>5.1.3 Video Codecs</td>
4537 <td>Added Android automotive requirements.</td>
4538 </tr>
4539 <tr>
4540 <td>7.1.1.3. Screen Density</td>
4541 <td>Added a new screen dpi (280dpi).</td>
4542 </tr>
4543 <tr>
4544 <td>7.1.5. Legacy Application Compatibility Mode</td>
4545 <td>Added Android automotive requirements.</td>
4546 </tr>
4547 <tr>
4548 <td>7.2 Input Devices</td>
4549 <td>Added general introduction statement.</td>
4550 </tr>
4551 <tr>
4552 <td>7.2.1. Keyboard</td>
4553 <td>Added Android Automotive requirements.</td>
4554 </tr>
4555 <tr>
4556 <td>7.2.3. Navigation Keys</td>
4557 <td>Added Android Automotive requirements.</td>
4558 </tr>
4559 <tr>
4560 <td>7.3.1. Accelerometer</td>
4561 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4562 </tr>
4563 <tr>
4564 <td>7.3.4. Gyroscope</td>
4565 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4566 </tr>
4567 <tr>
4568 <td>7.4.3 Bluetooth</td>
4569 <td>Added Android Automotive requirements.</td>
4570 </tr>
4571 <tr>
4572 <td>7.4.4. Near-Field Communications</td>
4573 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4574 </tr>
4575 <tr>
4576 <td>7.6.1. Minimum Memory and Storage</td>
4577 <td>Updated minimum memory requirements for lower resulution screen devices
4578 and added hard-limit requirement isLowRamDevice().</td>
4579 </tr>
4580 <tr>
4581 <td>7.6.2. Application Shared Storage</td>
4582 <td>Updated requirements when support for host machine access is mandatory.</td>
4583 </tr>
4584 <tr>
4585 <td>7.8.1. Microphone</td>
4586 <td>Added Android Automotive requirements.</td>
4587 </tr>
4588 <tr>
4589 <td>8.2. File I/O Access Performance</td>
4590 <td>Clarified requirements.</td>
4591 </tr>
4592 <tr>
4593 <td>9.8. Privacy</td>
4594 <td>Added privacy requirement for preloaded VPNs.</td>
4595 </tr>
4596 <tr>
4597 <td>9.9. Full-Disk Encryption</td>
4598 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4599 </tr>
4600 <tr>
4601 <td>9.10. Verified Boot</td>
4602 <td>Clarified definition of verified boot.</td>
4603 </tr>
4604 <tr>
4605 <td>11. Updatable Software</td>
4606 <td>Clarified the OTA download requirement is allowed but not mandatory for
4607 Android Automotive implementations.</td>
4608 </tr>
4609</table>
4610
4611
4612<h1 id="13_contact_us">13. Contact Us</h1>
4613
4614
4615<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
4616does not cover.</p>
4617
4618<h1 id="14_resources">14. Resources</h1>
4619
4620
4621<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4622
4623<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4624
4625<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>
4626
4627<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>
4628
4629<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4630
4631<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>
4632
4633<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>
4634
4635<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>
4636
4637<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>
4638
4639<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>
4640
4641<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>
4642
4643<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>
4644
4645<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4646
4647<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4648
4649<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>
4650
4651<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>
4652
4653<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4654
4655<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4656
4657<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4658
4659<p>20. Dalvik Executable Format and bytecode specification: available in the
4660Android source code, at dalvik/docs</p>
4661
4662<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>
4663
4664<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>
4665
4666<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>
4667
4668<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>
4669
4670<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4671
4672<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>
4673
4674<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>
4675
4676<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>
4677
4678<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>
4679
4680<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>
4681
4682<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>
4683
4684<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>
4685
4686<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>
4687
4688<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>
4689
4690<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>
4691
4692<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>
4693
4694<p>37. Settings.Secure LOCATION_MODE:</p>
4695
4696<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>
4697
4698<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>
4699
4700<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>
4701
4702<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>
4703
4704<p>41. Android Device Owner App:</p>
4705
4706<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>
4707
4708<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>
4709
4710<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>
4711
4712<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4713
4714<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>
4715
4716<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>
4717
4718<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>
4719
4720<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>
4721
4722<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>
4723
4724<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>
4725
4726<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>
4727
4728<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>
4729
4730<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4731
4732<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>
4733
4734<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>
4735
4736<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4737
4738<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4739
4740<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4741
4742<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>
4743
4744<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4745
4746<p>60. Android Application Development-Related Settings:</p>
4747
4748<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>
4749
4750<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>
4751
4752<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>
4753
4754<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4755
4756<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>
4757
4758<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>
4759
4760<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4761
4762<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>
4763
4764<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>
4765
4766<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>
4767
4768<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>
4769
4770<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>
4771
4772<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>
4773
4774<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>
4775
4776<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4777
4778<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>
4779
4780<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>
4781
4782<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>
4783
4784<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>
4785
4786<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>
4787
4788<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>
4789
4790<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>
4791
4792<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>
4793
4794<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>
4795
4796<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>
4797
4798<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>
4799
4800<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>
4801
4802<p>86. Android NFC Sharing Settings:</p>
4803
4804<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>
4805
4806<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>
4807
4808<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>
4809
4810<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>
4811
4812<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>
4813
4814<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>
4815
4816<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>
4817
4818<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>
4819
4820<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>
4821
4822<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>
4823
4824<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4825
4826<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>
4827
4828<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>
4829
4830<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>
4831
4832<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>
4833
4834<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>
4835
4836<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>
4837
4838<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>
4839
4840<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4841
4842<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>
4843
4844<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4845
4846<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>
4847
4848<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4849
4850<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>
4851
4852<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4853
4854<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>
4855
4856<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>
4857
4858<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>
4859
4860<p>Many of these resources are derived directly or indirectly from the Android
4861SDK, and will be functionally identical to the information in that SDK&rsquo;s
4862documentation. In any cases where this Compatibility Definition or the
4863Compatibility Test Suite disagrees with the SDK documentation, the SDK
4864documentation is considered authoritative. Any technical details provided in
4865the references included above are considered by inclusion to be part of this
4866Compatibility Definition.</p>
4867
4868</div>
4869</body>
4870</html>