Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / docs / source.android.com / d34ea08da129e9d05dcf8fb1749359928dca24c1 / . / src / compatibility / android-cdd.html
blob: 3032eafee0286a7d9c2189c29a46a120a834e487 [file] [log] [blame]
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1<!DOCTYPE html>
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>
Unsuk Jung06706432015-08-31 11:26:13 -0700[diff] [blame]868 <li>MUST report, via the above parameters, only those ABIs documented and
869described in the latest version of the Android NDK ABI Management documentation
870[<a href="https://developer.android.com/ndk/guides/abis.html">Resources, XX</a>],
871and MUST include support for the Advanced SIMD (a.k.a. NEON)
872[<a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0388f/Beijfcja.html">Resources,XX</a>]
873extension
874 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]875 <li>SHOULD be built using the source code and header files available in the
876upstream Android Open Source Project</li>
877</ul>
878
879<p>The following native code APIs MUST be available to apps that include native
880code:</p>
881
882<ul>
883 <li>libc (C library)</li>
884 <li>libm (math library)</li>
885 <li>Minimal support for C++</li>
886 <li>JNI interface</li>
887 <li>liblog (Android logging)</li>
888 <li>libz (Zlib compression)</li>
889 <li>libdl (dynamic linker)</li>
890 <li>libGLESv1_CM.so (OpenGL ES 1.x)</li>
891 <li>libGLESv2.so (OpenGL ES 2.0)</li>
892 <li>libGLESv3.so (OpenGL ES 3.x)</li>
893 <li>libEGL.so (native OpenGL surface management)</li>
894 <li>libjnigraphics.so</li>
895 <li>libOpenSLES.so (OpenSL ES 1.0.1 audio support)</li>
896 <li>libOpenMAXAL.so (OpenMAX AL 1.0.1 support)</li>
897 <li>libandroid.so (native Android activity support)</li>
898 <li>libmediandk.so (native media APIs support)</li>
899 <li>Support for OpenGL, as described below</li>
900</ul>
901
902<p>Note that future releases of the Android NDK may introduce support for
903additional ABIs. If a device implementation is not compatible with an existing
904predefined ABI, it MUST NOT report support for any ABIs at all.</p>
905
906<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
907(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
908Android 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
909symbols must be present, only the corresponding functions for OpenGL ES
910versions and extensions actually supported by the device must be fully
911implemented.</p>
912
913<p>Native code compatibility is challenging. For this reason, device implementers
914are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
915Android Open Source Project. </p>
916
917<h3 id="3_3_2_32-bit_arm_native_code_compatibility">
9183.3.2. 32-bit ARM Native Code Compatibility
919</h3>
920
921<p>The ARMv8 architecture deprecates several CPU operations, including some
922operations used in existing native code. On 64-bit ARM devices, the following
923deprecated operations MUST remain available to 32-bit native ARM code, either
924through native CPU support or through software emulation:</p>
925
926<ul>
927<li>SWP and SWPB instructions</li>
928<li>SETEND instruction</li>
929<li>CP15ISB, CP15DSB, and CP15DMB barrier operations</li>
930</ul>
931
932<p>Legacy versions of the Android NDK used /proc/cpuinfo to discover CPU features
933from 32-bit ARM native code. For compatibility with applications built using this
934NDK, devices MUST include the following lines in /proc/cpuinfo when it is read
935by 32-bit ARM applications:</p>
936
937<ul>
938<li>&quot;Features: &quot;, followed by a list of any optional ARMv7 CPU features
939supported by the device</li>
940<li>&quot;CPU architecture: &quot;, followed by an integer describing the device's
941highest supported ARM architecture (e.g., &quot;8&quot; for ARMv8 devices)</li>
942</ul>
943
944<p>These requirements only apply when /proc/cpuinfo is read by 32-bit ARM
945applications. Devices SHOULD not alter /proc/cpuinfo when read by 64-bit ARM or
946non-ARM applications.</p>
947
948<h2 id="3_4_web_compatibility">3.4. Web Compatibility</h2>
949
950
951<h3 id="3_4_1_webview_compatibility">3.4.1. WebView Compatibility</h3>
952
953<div class="note">
954<p>Android Watch devices MAY, but all other device implementations MUST provide
955a complete implementation of the android.webkit.Webview API.</p>
956</div>
957
958
959<p>The platform feature android.software.webview MUST be reported on any device
960that provides a complete implementation of the android.webkit.WebView API, and
961MUST NOT be reported on devices without a complete implementation of the API.
962The Android Open Source implementation uses code from the Chromium Project to
963implement 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
964rendering system, device implementers MUST use the specific upstream build of
965Chromium in the WebView implementation. Specifically:</p>
966
967<ul>
968 <li>Device android.webkit.WebView implementations MUST be based on the Chromium
969build from the upstream Android Open Source Project for Android ANDROID_VERSION. This build
970includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].</li>
971 <li>The user agent string reported by the WebView MUST be in this format:
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]972<p>Mozilla/5.0 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD)$(WEBVIEW))
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]973AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
974Safari/537.36</p>
975 <ul>
976 <li>The value of the $(VERSION) string MUST be the same as the value for
977android.os.Build.VERSION.RELEASE.</li>
978 <li>The $(WEBVIEW) string MAY be omitted, but if included MUST be "; wv" to
979 note that this is a webview</li>
980 <li>The value of the $(MODEL) string MUST be the same as the value for
981android.os.Build.MODEL.</li>
982 <li>The value of the $(BUILD) string MUST be the same as the value for
983android.os.Build.ID.</li>
984 <li>The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
985upstream Android Open Source Project.</li>
986 <li>Device implementations MAY omit Mobile in the user agent string.</li>
987 </ul></li></ul>
988
989<p>The WebView component SHOULD include support for as many HTML5 features as
990possible and if it supports the feature SHOULD conform to the HTML5
991specification [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>].</p>
992
993<h3 id="3_4_2_browser_compatibility">3.4.2. Browser Compatibility</h3>
994
995<div class="note">
996<p>Android Television, Watch, and Android Automotive implementations MAY omit a
997browser application, but MUST support the public intent patterns as described in
998<a href="#3_2_3_1_core_application_intents">section 3.2.3.1</a>. All other types
999of device implementations MUST include a standalone Browser application for
1000general user web browsing.</p>
1001</div>
1002
1003<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1004However, even if an alternate Browser application is used, the
1005android.webkit.WebView component provided to third-party applications MUST be
1006based on WebKit, as described in <a href="#3_4_1_webview_compatibility">section 3.4.1</a>.</p>
1007
1008<p>Implementations MAY ship a custom user agent string in the standalone Browser
1009application.</p>
1010
1011<p>The standalone Browser application (whether based on the upstream WebKit
1012Browser application or a third-party replacement) SHOULD include support for as
1013much of HTML5 [<a href="http://html.spec.whatwg.org/multipage/">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1014APIs associated with HTML5:</p>
1015
1016<ul>
1017 <li>application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]</li>
1018 <li>the &#60;video&#62; tag [<a href="http://www.w3.org/html/wg/drafts/html/master/semantics.html#video">Resources, 16</a>]</li>
1019 <li>geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]</li>
1020</ul>
1021
1022<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1023[<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
1024IndexedDB over webstorage, IndexedDB is expected to become a required component
1025in a future version of Android.</p>
1026
1027<h2 id="3_5_api_behavioral_compatibility">3.5. API Behavioral Compatibility</h2>
1028
1029
1030<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1031consistent with the preferred implementation of the upstream Android Open
1032Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1033
1034<ul>
1035 <li>Devices MUST NOT change the behavior or semantics of a standard intent.</li>
1036 <li>Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1037type of system component (such as Service, Activity, ContentProvider, etc.).</li>
1038 <li>Devices MUST NOT change the semantics of a standard permission.</li>
1039</ul>
1040
1041<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1042significant portions of the platform for behavioral compatibility, but not all.
1043It is the responsibility of the implementer to ensure behavioral compatibility
1044with the Android Open Source Project. For this reason, device implementers
1045SHOULD use the source code available via the Android Open Source Project where
1046possible, rather than re-implement significant parts of the system.</p>
1047
1048<h2 id="3_6_api_namespaces">3.6. API Namespaces</h2>
1049
1050
1051<p>Android follows the package and class namespace conventions defined by the Java
1052programming language. To ensure compatibility with third-party applications,
1053device implementers MUST NOT make any prohibited modifications (see below) to
1054these package namespaces:</p>
1055
1056<ul>
1057 <li>java.*</li>
1058 <li>javax.*</li>
1059 <li>sun.*</li>
1060 <li>android.*</li>
1061 <li>com.android.*</li>
1062</ul>
1063
1064<p><strong>Prohibited modifications include</strong>:</p>
1065
1066<ul>
1067 <li>Device implementations MUST NOT modify the publicly exposed APIs on the Android
1068platform by changing any method or class signatures, or by removing classes or
1069class fields.</li>
1070 <li>Device implementers MAY modify the underlying implementation of the APIs, but
1071such modifications MUST NOT impact the stated behavior and Java-language
1072signature of any publicly exposed APIs.</li>
1073 <li>Device implementers MUST NOT add any publicly exposed elements (such as classes
1074or interfaces, or fields or methods to existing classes or interfaces) to the
1075APIs above.</li>
1076</ul>
1077
1078<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,
1079device implementers MUST NOT expose new APIs or alter existing APIs in the
1080namespaces noted above. Device implementers MAY make internal-only
1081modifications, but those modifications MUST NOT be advertised or otherwise
1082exposed to developers.</p>
1083
1084<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1085namespace owned by or referring to another organization. For instance, device
1086implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1087Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1088namespaces. Additionally, if a device implementation includes custom APIs
1089outside the standard Android namespace, those APIs MUST be packaged in an
1090Android shared library so that only apps that explicitly use them (via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1091lt;uses-librarygt; mechanism) are affected by the increased memory usage of such
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1092APIs.</p>
1093
1094<p>If a device implementer proposes to improve one of the package namespaces above
1095(such as by adding useful new functionality to an existing API, or adding a new
1096API), 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
1097information on that site.</p>
1098
1099<p>Note that the restrictions above correspond to standard conventions for naming
1100APIs in the Java programming language; this section simply aims to reinforce
1101those conventions and make them binding through inclusion in this Compatibility
1102Definition.</p>
1103
1104<h2 id="3_7_runtime_compatibility">3.7. Runtime Compatibility</h2>
1105
1106
1107<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1108Dalvik 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
1109the Dalvik Executable Format, and the reference implementation&rsquo;s package
1110management system.</p>
1111
1112<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1113accordance with the upstream Android platform, and as specified by the
1114following table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and screen density definitions.)</p>
1115
1116<p>Note that memory values specified below are considered minimum values and
1117device implementations MAY allocate more memory per application.</p>
1118
1119<table>
1120 <tr>
1121 <th>Screen Layout</th>
1122 <th>Screen Density</th>
1123 <th>Minimum Application Memory</th>
1124 </tr>
1125 <tr>
1126 <td rowspan="10">small/normal</td>
1127 <td>120 dpi (ldpi)</td>
1128 <td rowspan="2">32MB</td>
1129 </tr>
1130 <tr>
1131 <td>160 dpi (mdpi)</td>
1132 </tr>
1133 <tr>
1134 <td>213 dpi (tvdpi)</td>
1135 <td rowspan="3">48MB</td>
1136 </tr>
1137 <tr>
1138 <td>240 dpi (hdpi)</td>
1139 </tr>
1140 <tr>
1141 <td>280 dpi (280dpi)</td>
1142 </tr>
1143 <tr>
1144 <td>320 dpi (xhdpi)</td>
1145 <td>80MB</td>
1146 </tr>
1147 <tr>
1148 <td>400 dpi (400dpi)</td>
1149 <td>96MB</td>
1150 </tr>
1151 <tr>
1152 <td>480 dpi (xxhdpi)</td>
1153 <td>128MB</td>
1154 </tr>
1155 <tr>
1156 <td>560 dpi (560dpi)</td>
1157 <td>192MB</td>
1158 </tr>
1159 <tr>
1160 <td>640 dpi (xxxhdpi)</td>
1161 <td>256MB</td>
1162 </tr>
1163 <tr>
1164 <td rowspan="10">large</td>
1165 <td>120 dpi (ldpi)</td>
1166 <td>32MB</td>
1167 </tr>
1168 <tr>
1169 <td>160 dpi (mdpi)</td>
1170 <td>48MB</td>
1171 </tr>
1172 <tr>
1173 <td>213 dpi (tvdpi)</td>
1174 <td rowspan="2">80MB</td>
1175 </tr>
1176 <tr>
1177 <td>240 dpi (hdpi)</td>
1178 </tr>
1179 <tr>
1180 <td>280 dpi (280dpi)</td>
1181 <td>96MB</td>
1182 </tr>
1183 <tr>
1184 <td>320 dpi (xhdpi)</td>
1185 <td>128MB</td>
1186 </tr>
1187 <tr>
1188 <td>400 dpi (400dpi)</td>
1189 <td>192MB</td>
1190 </tr>
1191 <tr>
1192 <td>480 dpi (xxhdpi)</td>
1193 <td>256MB</td>
1194 </tr>
1195 <tr>
1196 <td>560 dpi (560dpi)</td>
1197 <td>384MB</td>
1198 </tr>
1199 <tr>
1200 <td>640 dpi (xxxhdpi)</td>
1201 <td>512MB</td>
1202 </tr>
1203 <tr>
1204 <td rowspan="10">xlarge</td>
1205 <td>120 dpi (ldpi)</td>
1206 <td>48MB</td>
1207 </tr>
1208 <tr>
1209 <td>160 dpi (mdpi)</td>
1210 <td>80MB</td>
1211 </tr>
1212 <tr>
1213 <td>213 dpi (tvdpi)</td>
1214 <td rowspan="2">96MB</td>
1215 </tr>
1216 <tr>
1217 <td>240 dpi (hdpi)</td>
1218 </tr>
1219 <tr>
1220 <td>280 dpi (280dpi)</td>
1221 <td>144MB</td>
1222 </tr>
1223 <tr>
1224 <td>320 dpi (xhdpi)</td>
1225 <td>192MB</td>
1226 </tr>
1227 <tr>
1228 <td>400 dpi (400dpi)</td>
1229 <td>288MB</td>
1230 </tr>
1231 <tr>
1232 <td>480 dpi (xxhdpi)</td>
1233 <td>384MB</td>
1234 </tr>
1235 <tr>
1236 <td>560 dpi (560dpi)</td>
1237 <td>576MB</td>
1238 </tr>
1239 <tr>
1240 <td>640 dpi (xxxhdpi)</td>
1241 <td>768MB</td>
1242 </tr>
1243</table>
1244
1245
1246<h2 id="3_8_user_interface_compatibility">3.8. User Interface Compatibility</h2>
1247
1248
1249<h3 id="3_8_1_launcher_home_screen">3.8.1. Launcher (Home Screen)</h3>
1250
1251
1252<p>Android includes a launcher application (home screen) and support for
1253third-party applications to replace the device launcher (home screen). Device
1254implementations that allow third-party applications to replace the device home
1255screen MUST declare the platform feature android.software.home_screen.</p>
1256
1257<h3 id="3_8_2_widgets">3.8.2. Widgets</h3>
1258
1259<div class="note">
1260<p>Widgets are optional for all Android device implementations, but SHOULD be
1261supported on Android Handheld devices.</p>
1262</div>
1263
1264
1265<p>Android defines a component type and corresponding API and lifecycle that
1266allows 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
1267implementations. Device implementations that support embedding widgets on the
1268home screen MUST meet the following requirements and declare support for
1269platform feature android.software.app_widgets.</p>
1270
1271<ul>
1272 <li>Device launchers MUST include built-in support for AppWidgets, and expose user
1273interface affordances to add, configure, view, and remove AppWidgets directly
1274within the Launcher.</li>
1275 <li>Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1276the standard grid size. See the App Widget Design Guidelines in the Android SDK
1277documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.</li>
1278 <li>Device implementations that include support for lock screen MAY support
1279application widgets on the lock screen.</li>
1280</ul>
1281
1282<h3 id="3_8_3_notifications">3.8.3. Notifications</h3>
1283
1284
1285<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>
1286
1287<p>Some APIs allow applications to perform notifications or attract attention
1288using hardware&#8212;specifically sound, vibration, and light. Device implementations
1289MUST support notifications that use hardware features, as described in the SDK
1290documentation, and to the extent possible with the device implementation
1291hardware. For instance, if a device implementation includes a vibrator, it MUST
1292correctly implement the vibration APIs. If a device implementation lacks
1293hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1294is further detailed in <a href="#7_hardware_compatibility">section 7</a>.</p>
1295
1296<p>Additionally, the implementation MUST correctly render all resources (icons, animation files
1297etc.) provided for in the APIs
1298[<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>],
1299or in the Status/System Bar icon style guide
1300[<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>],
1301which in the case of an Android Television device includes the possibility to not display the
1302notifications. Device implementers MAY provide an alternative user experience for
1303notifications than that provided by the reference Android Open Source
1304implementation; however, such alternative notification systems MUST support
1305existing notification resources, as above. </p>
1306
1307<p>Android includes support for various notifications, such as:</p>
1308
1309<ul>
1310 <li><strong>Rich notifications</strong>. Interactive Views for ongoing notifications.</li>
1311 <li><strong>Heads-up notifications</strong>. Interactive Views users can act on or dismiss without leaving the current app.</li>
1312 <li><strong>Lockscreen notifications</strong>. Notifications shown over a lock screen with granular control on visibility.</li>
1313</ul>
1314
1315<p>Android device implementations, when such notifications are made visible, MUST properly execute
1316Rich and Heads-up notifications and include the title/name, icon, text as documented in the Android
1317APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.
1318</p>
1319
1320<p>Android includes Notification Listener Service APIs that allow apps (once
1321explicitly enabled by the user) to receive a copy of all notifications as they
1322are posted or updated. Device implementations MUST correctly and promptly send
1323notifications in their entirety to all such installed and user-enabled listener
1324services, including any and all metadata attached to the Notification object.</p>
1325
1326<h3 id="3_8_4_search">3.8.4. Search</h3>
1327
1328
1329<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
1330expose their application&rsquo;s data into the global system search. Generally
1331speaking, this functionality consists of a single, system-wide user interface
1332that allows users to enter queries, displays suggestions as users type, and
1333displays results. The Android APIs allow developers to reuse this interface to
1334provide search within their own apps, and allow developers to supply results to
1335the common global search user interface.</p>
1336
1337<p>Android device implementations SHOULD include global search, a single, shared,
1338system-wide search user interface capable of real-time suggestions in response
1339to user input. Device implementations SHOULD implement the APIs that allow
1340developers to reuse this user interface to provide search within their own
1341applications. Device implementations that implement the global search interface
1342MUST implement the APIs that allow third-party applications to add suggestions
1343to the search box when it is run in global search mode. If no third-party
1344applications are installed that make use of this functionality, the default
1345behavior SHOULD be to display web search engine results and suggestions.</p>
1346
1347<h3 id="3_8_5_toasts">3.8.5. Toasts</h3>
1348
1349
1350<p>Applications can use the &ldquo;Toast&rdquo; API to display short non-modal strings to the
1351end 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
1352some high-visibility manner.</p>
1353
1354<h3 id="3_8_6_themes">3.8.6. Themes</h3>
1355
1356
1357<p>Android provides &ldquo;themes&rdquo; as a mechanism for applications to apply styles
1358across an entire Activity or application.</p>
1359
1360<p>Android includes a &ldquo;Holo&rdquo; theme family as a set of defined styles for
1361application developers to use if they want to match the Holo theme look and
1362feel 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
1363exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1364
1365<p>Android includes a &ldquo;Material&rdquo; theme family as a set of defined styles for
1366application developers to use if they want to match the design theme&rsquo;s look and
1367feel across the wide variety of different Android device types. Device
1368implementations MUST support the &ldquo;Material&rdquo; theme family and MUST NOT alter any
1369of 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>
1370
1371<p>Android also includes a &ldquo;Device Default&rdquo; theme family as a set of defined
1372styles for application developers to use if they want to match the look and
1373feel of the device theme as defined by the device implementer. Device
1374implementations MAY modify the Device Default theme attributes exposed to
1375applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1376
1377<p>Android supports a new variant theme with translucent system bars, which allows
1378application developers to fill the area behind the status and navigation bar
1379with their app content. To enable a consistent developer experience in this
1380configuration, it is important the status bar icon style is maintained across
1381different device implementations. Therefore, Android device implementations
1382MUST use white for system status icons (such as signal strength and battery
1383level) and notifications issued by the system, unless the icon is indicating a
1384problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1385
1386<h3 id="3_8_7_live_wallpapers">3.8.7. Live Wallpapers</h3>
1387
1388
1389<p>Android defines a component type and corresponding API and lifecycle that
1390allows 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
1391input capabilities that display as a wallpaper, behind other applications.</p>
1392
1393<p>Hardware is considered capable of reliably running live wallpapers if it can
1394run all live wallpapers, with no limitations on functionality, at a reasonable
1395frame rate with no adverse effects on other applications. If limitations in the
1396hardware cause wallpapers and/or applications to crash, malfunction, consume
1397excessive CPU or battery power, or run at unacceptably low frame rates, the
1398hardware is considered incapable of running live wallpaper. As an example, some
1399live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1400Live wallpaper will not run reliably on hardware that does not support multiple
1401OpenGL contexts because the live wallpaper use of an OpenGL context may
1402conflict with other applications that also use an OpenGL context.</p>
1403
1404<p>Device implementations capable of running live wallpapers reliably as described
1405above SHOULD implement live wallpapers, and when implemented MUST report the
1406platform feature flag android.software.live_wallpaper.</p>
1407
1408<h3 id="3_8_8_activity_switching">3.8.8. Activity Switching</h3>
1409
1410<div class="note">
1411<p>As the Recent function navigation key is OPTIONAL, the requirements to
1412implement the overview screen is OPTIONAL for Android Television devices and
1413Android Watch devices.</p>
1414</div>
1415
1416
1417<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
1418accessed activities and tasks using a thumbnail image of the application&rsquo;s
1419graphical state at the moment the user last left the application. Device
1420implementations 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>
1421
1422<ul>
1423 <li>MUST display affiliated recents as a group that moves together.</li>
1424 <li>MUST support at least up to 20 displayed activities.</li>
1425 <li>MUST at least display the title of 4 activities at a time.</li>
1426 <li>SHOULD display highlight color, icon, screen title in recents.</li>
1427 <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>
1428 <li>SHOULD display a closing affordance ("x") but MAY delay this until user
1429interacts with screens.</li>
1430</ul>
1431
1432<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1433interface (or a similar thumbnail-based interface) for the overview screen.</p>
1434
1435<h3 id="3_8_9_input_management">3.8.9. Input Management</h3>
1436
1437
1438<p>Android includes support for Input Management and support for third-party input
1439method 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
1440the device MUST declare the platform feature android.software.input_methods and
1441support IME APIs as defined in the Android SDK documentation.</p>
1442
1443<p>Device implementations that declare the android.software.input_methods feature
1444MUST provide a user-accessible mechanism to add and configure third-party input
1445methods. Device implementations MUST display the settings interface in response
1446to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1447
1448<h3 id="3_8_10_lock_screen_media_control">3.8.10. Lock Screen Media Control</h3>
1449
1450
1451<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1452Media Notification Template that allows media applications to integrate with
1453playback controls that are displayed on the lock screen [<a href="http://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>].
1454Device implementations that support a lock screen, unless an Android Automotive or Watch
1455implementation, MUST display the Lockscreen Notifications including the Media Notification
1456Template.</p>
1457
1458<h3 id="3_8_11_dreams">3.8.11. Dreams</h3>
1459
1460
1461<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
1462a power source is idle or docked in a desk dock. Android Watch devices MAY
1463implement Dreams, but other types of device implementations SHOULD include
1464support for Dreams and provide a settings option for users to configure Dreams
1465in response to the android.settings.DREAM_SETTINGS intent.</p>
1466
1467<h3 id="3_8_12_location">3.8.12. Location</h3>
1468
1469
1470<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1471location coordinates, location modes MUST be displayed in the Location menu
1472within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>].</p>
1473
1474<h3 id="3_8_13_unicode_and_font">3.8.13. Unicode and Font</h3>
1475
1476
1477<p>Android includes support for color emoji characters. When Android device
1478implementations include an IME, devices SHOULD provide an input method to the
1479user 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>
1480
1481<p>Android includes support for Roboto 2 font with different
1482weights&mdash;sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1483sans-serif-condensed, sans-serif-condensed-light&mdash;which MUST all be included for
1484the languages available on the device and full Unicode 7.0 coverage of Latin,
1485Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1486all glyphs in the currency symbols block of Unicode 7.0.</p>
1487
1488<h2 id="3_9_device_administration">3.9. Device Administration</h2>
1489
1490
1491<p>Android includes features that allow security-aware applications to perform
1492device administration functions at the system level, such as enforcing password
1493policies or performing remote wipe, through the Android Device Administration
1494API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>].
1495Device implementations MUST provide an implementation of the DevicePolicyManager class
1496[<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>].
1497Device implementations that include support for PIN (numeric) or PASSWORD
1498(alphanumeric) based lock screens MUST support the full range of device
1499administration policies defined in the Android SDK documentation
1500[<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]
1501and report the platform feature android.software.device_admin.</p>
1502
1503<p>Device implementations MAY have a preinstalled application performing device
1504administration functions but this application MUST NOT be set out-of-the box as
1505the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1506
1507<h2 id="3_10_accessibility">3.10. Accessibility</h2>
1508
1509
1510<p>Android provides an accessibility layer that helps users with disabilities to
1511navigate their devices more easily. In addition, Android provides platform APIs
1512that enable accessibility service implementations to receive callbacks for user
1513and system events and generate alternate feedback mechanisms, such as
1514text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>].</p>
1515
1516<p>Device implementations include the following requirements:</p>
1517
1518<ul>
1519<li>Android Automotive implementations SHOULD provide an implementation of the
1520Android accessibility framework consistent with the default Android
1521implementation.</li>
1522<li>Device implementations (Android Automotive excluded) MUST provide an
1523implementation of the Android accessibility framework consistent with the
1524default Android implementation.</li>
1525<li>Device implementations (Android Automotive excluded) MUST support
1526third-party accessibility service implementations through the
1527android.accessibilityservice APIs
1528[<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]</li>
1529<li>Device implementations (Android Automotive excluded) MUST generate
1530AccessibilityEvents and deliver these events to all registered
1531AccessibilityService implementations in a manner consistent with the default
1532Android implementation</li>
1533<li> Device implementations (Android Automotive and Android Watch devices with
1534no audio output excluded), MUST provide a user-accessible mechanism to enable
1535and disable accessibility services, and MUST display this interface in response
1536to the android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.</li>
1537</ul>
1538
1539<p>Additionally, device implementations SHOULD provide an implementation of an
1540accessibility service on the device, and SHOULD provide a mechanism for users
1541to enable the accessibility service during device setup. An open source
1542implementation of an accessibility service is available from the Eyes Free
1543project [<a href="http://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1544
1545<h2 id="3_11_text-to-speech">3.11. Text-to-Speech</h2>
1546
1547
1548<p>Android includes APIs that allow applications to make use of text-to-speech
1549(TTS) services and allows service providers to provide implementations of TTS
1550services [<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
1551MUST meet these requirements related to the Android TTS framework. </p>
1552
1553<p>Android Automotive implementations:</p>
1554<ul>
1555<li>MUST support the Android TTS framework APIs.</li>
1556<li>MAY support installation of third-party TTS engines. If supported, partners
1557MUST provide a user-accessible interface that allows the user to select a TTS
1558engine for use at system level.</li>
1559</ul>
1560
1561<p>All other device implementations:</p>
1562
1563<ul>
1564 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1565supporting the languages available on the device. Note that the upstream
1566Android open source software includes a full-featured TTS engine
1567implementation.
1568 <li> MUST support installation of third-party TTS engines
1569 <li> MUST provide a user-accessible interface that allows users to select a TTS
1570engine for use at the system level
1571</ul>
1572
1573<h2 id="3_12_tv_input_framework">3.12. TV Input Framework</h2>
1574
1575
1576<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1577content to Android Television devices. TIF provides a standard API to create
1578input modules that control Android Television devices. Android Television
1579device implementations MUST support Television Input Framework [<a href="http://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1580
1581<p>Device implementations that support TIF MUST declare the platform feature
1582android.software.live_tv.</p>
1583
1584<h1 id="4_application_packaging_compatibility">4. Application Packaging Compatibility</h1>
1585
1586
1587<p>Device implementations MUST install and run Android &ldquo;.apk&rdquo; files as generated
1588by 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>
1589
1590<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
1591files from installing and running correctly on other compatible devices.</p>
1592
1593<h1 id="5_multimedia_compatibility">5. Multimedia Compatibility</h1>
1594
1595
1596<h2 id="5_1_media_codecs">5.1. Media Codecs</h2>
1597
1598
1599<p>Device implementations MUST support the core media formats specified in the
1600Android 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
1601implementations MUST support the media formats, encoders, decoders, file types,
1602and container formats defined in the tables below and reported via MediaCodecList
1603[<a href="http://developer.android.com/reference/android/media/MediaCodecList.html">Resources,112</a>].
1604Device implementations MUST also be able to decode all profiles reported in its CamcorderProfile
1605[<a href="http://developer.android.com/reference/android/media/CamcorderProfile.html">Resources,
1606113</a>].
1607
1608All of these codecs are
1609provided as software implementations in the preferred Android implementation
1610from the Android Open Source Project.</p>
1611
1612<p>Please note that neither Google nor the Open Handset Alliance make any
1613representation that these codecs are free from third-party patents. Those
1614intending to use this source code in hardware or software products are advised
1615that implementations of this code, including in open source software or
1616shareware, may require patent licenses from the relevant patent holders.</p>
1617
1618<h3 id="5_1_1_audio_codecs">5.1.1. Audio Codecs</h3>
1619
1620<table>
1621 <tr>
1622 <th>Format/Codec</th>
1623 <th>Encoder</th>
1624 <th>Decoder</th>
1625 <th>Details</th>
1626 <th>Supported File Types/Container Formats</th>
1627 </tr>
1628 <tr>
1629 <td>MPEG-4 AAC Profile</p>
1630
1631<p>(AAC LC)</td>
1632 <td>REQUIRED<sup>1</sup></td>
1633 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1634 <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]163548 kHz.</td>
1636 <td>
1637 <ul>
1638 <li class="table_list">3GPP (.3gp)</li>
1639 <li class="table_list">MPEG-4 (.mp4, .m4a)</li>
1640 <li class="table_list">ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1641supported)</li>
1642 <li class="table_list">MPEG-TS (.ts, not seekable, Android 3.0+)</li></ul></td>
1643 </tr>
1644 <tr>
1645 <td>MPEG-4 HE AAC Profile (AAC+)</td>
1646 <td>REQUIRED<sup>1</sup><br>(Android 4.1+)</td>
1647 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1648 <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]1649to 48 kHz.</td>
1650 <td></td>
1651 </tr>
1652 <tr>
1653 <td>MPEG-4 HE AACv2</p>
1654
1655<p>Profile (enhanced AAC+)</td>
1656 <td> </td>
1657 <td>REQUIRED</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1658 <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]1659to 48 kHz.</td>
1660 <td></td>
1661 </tr>
1662 <tr>
1663 <td>AAC ELD (enhanced low delay AAC)</td>
1664 <td>REQUIRED<sup>1</sup> </p>
1665
1666<p>(Android 4.1+)</td>
1667 <td>REQUIRED</p>
1668
1669<p>(Android 4.1+)</td>
1670 <td>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</td>
1671 <td></td>
1672 </tr>
1673 <tr>
1674 <td>AMR-NB</td>
1675 <td>REQUIRED<sup>3</sup></td>
1676 <td>REQUIRED<sup>3</sup></td>
1677 <td>4.75 to 12.2 kbps sampled @ 8kHz</td>
1678 <td>3GPP (.3gp)</td>
1679 </tr>
1680 <tr>
1681 <td>AMR-WB</td>
1682 <td>REQUIRED<sup>3</sup></td>
1683 <td>REQUIRED<sup>3</sup></td>
1684 <td>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</td>
1685 <td></td>
1686 </tr>
1687 <tr>
1688 <td>FLAC</td>
1689 <td></td>
1690 <td>REQUIRED <br>(Android 3.1+)</td>
1691 <td>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
1692recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
1693does not include a low-pass filter). 16-bit recommended; no dither applied for
169424-bit.</td>
1695 <td>FLAC (.flac) only</td>
1696 </tr>
1697 <tr>
1698 <td>MP3</td>
1699 <td></td>
1700 <td>REQUIRED</td>
1701 <td>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</td>
1702 <td>MP3 (.mp3)</td>
1703 </tr>
1704 <tr>
1705 <td>MIDI</td>
1706 <td></td>
1707 <td>REQUIRED</td>
1708 <td>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
1709ringtone formats RTTTL/RTX, OTA, and iMelody</td>
1710 <td><ul>
1711 <li class="table_list">Type 0 and 1 (.mid, .xmf, .mxmf)</li>
1712 <li class="table_list">RTTTL/RTX (.rtttl, .rtx)</li>
1713 <li class="table_list">OTA (.ota)</li>
1714 <li class="table_list">iMelody (.imy)</li></ul></td>
1715 </tr>
1716 <tr>
1717 <td>Vorbis</td>
1718 <td></td>
1719 <td>REQUIRED</td>
1720 <td></td>
1721 <td><ul>
1722 <li class="table_list">Ogg (.ogg)</li>
1723 <li class="table_list">Matroska (.mkv, Android 4.0+)</li></ul></td>
1724 </tr>
1725 <tr>
1726 <td>PCM/WAVE</td>
1727 <td>REQUIRED<sup>4</sup><br> (Android 4.1+)</td>
1728 <td>REQUIRED</td>
1729 <td>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
1730sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
1731frequencies.</td>
1732 <td>WAVE (.wav)</td>
1733 </tr>
1734 <tr>
1735 <td>Opus</td>
1736 <td></td>
1737 <td>REQUIRED<br> (Android 5.0+)</td>
1738 <td></td>
1739 <td>Matroska (.mkv)</td>
1740 </tr>
1741</table>
1742
1743
1744<p class="table_footnote"> 1 Required for device implementations that define android.hardware.microphone
1745but optional for Android Watch device implementations.</p>
1746
1747<p class="table_footnote">2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
17482 channels is optional.</p>
1749
1750<p class="table_footnote">3 Required for Android Handheld device implementations. </p>
1751
1752<p class="table_footnote">4 Required for device implementations that define android.hardware.microphone,
1753including Android Watch device implementations.</p>
1754
1755<h3 id="5_1_2_image_codecs">5.1.2. Image Codecs</h3>
1756
1757<table>
1758 <tr>
1759 <th>Format/Codec</th>
1760 <th>Encoder</th>
1761 <th>Decoder</th>
1762 <th>Details</th>
1763 <th>Supported File Types/Container Formats</th>
1764 </tr>
1765 <tr>
1766 <td>JPEG</td>
1767 <td>REQUIRED</td>
1768 <td>REQUIRED</td>
1769 <td>Base+progressive</td>
1770 <td>JPEG (.jpg)</td>
1771 </tr>
1772 <tr>
1773 <td>GIF</td>
1774 <td></td>
1775 <td>REQUIRED</td>
1776 <td></td>
1777 <td>GIF (.gif)</td>
1778 </tr>
1779 <tr>
1780 <td>PNG</td>
1781 <td>REQUIRED</td>
1782 <td>REQUIRED</td>
1783 <td></td>
1784 <td>PNG (.png)</td>
1785 </tr>
1786 <tr>
1787 <td>BMP</td>
1788 <td></td>
1789 <td>REQUIRED</td>
1790 <td></td>
1791 <td>BMP (.bmp)</td>
1792 </tr>
1793 <tr>
1794 <td>WebP</td>
1795 <td>REQUIRED</td>
1796 <td>REQUIRED</td>
1797 <td></td>
1798 <td>WebP (.webp)</td>
1799 </tr>
1800</table>
1801
1802
1803<h3 id="5_1_3_video_codecs">5.1.3. Video Codecs</h3>
1804
1805<p>Video codecs are optional for Android Watch device implementations.</p>
1806
1807<table>
1808 <tr>
1809 <th>Format/Codec</th>
1810 <th>Encoder</th>
1811 <th>Decoder</th>
1812 <th>Details</th>
1813 <th>Supported File Types/<br>Container Formats</th>
1814 </tr>
1815 <tr>
1816 <td>H.263</td>
1817 <td>REQUIRED<sup>1</sup></td>
1818 <td>REQUIRED<sup>2</sup></td>
1819 <td></td>
1820 <td><ul>
1821 <li class="table_list">3GPP (.3gp)</li>
1822 <li class="table_list">MPEG-4 (.mp4)</li></ul></td>
1823 </tr>
1824 <tr>
1825 <td>H.264 AVC</td>
1826 <td>REQUIRED<sup>2</sup></td>
1827 <td>REQUIRED<sup>2</sup></td>
1828 <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>
1829 <td><ul>
1830 <li class="table_list">3GPP (.3gp)</li>
1831 <li class="table_list">MPEG-4 (.mp4)</li>
1832 <li class="table_list">MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</li></ul></td>
1833 </tr>
1834 <tr>
1835 <td>H.265 HEVC</td>
1836 <td></td>
1837 <td>REQUIRED<sup>5</sup></td>
1838 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1839 <td>MPEG-4 (.mp4)</td>
1840 </tr>
1841 <tr>
1842 <td>MPEG-4 SP</td>
1843 <td></td>
1844 <td>REQUIRED<sup>2</sup></td>
1845 <td></td>
1846 <td>3GPP (.3gp)</td>
1847 </tr>
1848 <tr>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1849 <td>VP8<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1850 <td>REQUIRED<sup>2</sup></p>
1851
1852<p>(Android 4.3+)</td>
1853 <td>REQUIRED<sup>2</sup></p>
1854
1855<p>(Android 2.3.3+)</td>
1856 <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>
1857 <td><ul>
1858 <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]1859 <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]1860 </tr>
1861 <tr>
1862 <td>VP9</td>
1863 <td></td>
1864 <td>REQUIRED<sup>2</sup><br> (Android 4.4+)</td>
1865 <td>See <a href="#5_3_video_decoding">section 5.3</a> for details</td>
1866 <td><ul>
1867 <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]1868 <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]1869 </tr>
1870</table>
1871
1872
1873<p class="table_footnote">1 Required for device implementations that include camera hardware and define
1874android.hardware.camera or android.hardware.camera.front.</p>
1875
1876<p class="table_footnote">2 Required for device implementations except Android Watch devices. </p>
1877
1878<p class="table_footnote">3 For acceptable quality of web video streaming and video-conference services,
1879device implementations SHOULD use a hardware VP8 codec that meets the
1880requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
1881
1882<p class="table_footnote">4 Device implementations SHOULD support writing Matroska WebM files.</p>
1883
1884<p class="table_footnote">5 Strongly recommended for Android Automotive, optional for Android Watch, and required for all other device types.</p>
1885
1886<h2 id="5_2_video_encoding">5.2. Video Encoding</h2>
1887
1888<div class="note">
1889<p>Video codecs are optional for Android Watch device implementations.</p>
1890</div>
1891
1892
1893<p>Android device implementations with H.264 codec support, MUST support Baseline
1894Profile Level 3 and the following SD (Standard Definition) video encoding
1895profiles and SHOULD support Main Profile Level 4 and the following HD (High
1896Definition) video encoding profiles. Android Television devices are STRONGLY
1897RECOMMENDED to encode HD 1080p video at 30 fps.</p>
1898<table>
1899 <tr>
1900 <th></th>
1901 <th>SD (Low quality)</th>
1902 <th>SD (High quality)</th>
1903 <th>HD 720p1</th>
1904 <th>HD 1080p1</th>
1905 </tr>
1906 <tr>
1907 <th>Video resolution</th>
1908 <td>320 x 240 px</td>
1909 <td>720 x 480 px</td>
1910 <td>1280 x 720 px</td>
1911 <td>1920 x 1080 px</td>
1912 </tr>
1913 <tr>
1914 <th>Video frame rate</th>
1915 <td>20 fps</td>
1916 <td>30 fps</td>
1917 <td>30 fps</td>
1918 <td>30 fps</td>
1919 </tr>
1920 <tr>
1921 <th>Video bitrate</th>
1922 <td>384 Kbps</td>
1923 <td>2 Mbps</td>
1924 <td>4 Mbps</td>
1925 <td>10 Mbps</td>
1926 </tr>
1927</table>
1928
1929
1930<p class="table_footnote">1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
1931devices.</p>
1932
1933<p>Android device implementations with VP8 codec support MUST support the SD video
1934encoding profiles and SHOULD support the following HD (High Definition) video
1935encoding profiles.</p>
1936<table>
1937 <tr>
1938 <th></th>
1939 <th>SD (Low quality)</th>
1940 <th>SD (High quality)</th>
1941 <th>HD 720p1</th>
1942 <th>HD 1080p1</th>
1943 </tr>
1944 <tr>
1945 <th>Video resolution</th>
1946 <td>320 x 180 px</td>
1947 <td>640 x 360 px</td>
1948 <td>1280 x 720 px</td>
1949 <td>1920 x 1080 px</td>
1950 </tr>
1951 <tr>
1952 <th>Video frame rate</th>
1953 <td>30 fps</td>
1954 <td>30 fps</td>
1955 <td>30 fps</td>
1956 <td>30 fps</td>
1957 </tr>
1958 <tr>
1959 <th>Video bitrate</th>
1960 <td>800 Kbps </td>
1961 <td>2 Mbps</td>
1962 <td>4 Mbps</td>
1963 <td>10 Mbps</td>
1964 </tr>
1965</table>
1966
1967<p class="table_footnote">1 When supported by hardware.</p>
1968
1969<h2 id="5_3_video_decoding">5.3. Video Decoding</h2>
1970
1971<div class="note">
1972<p>Video codecs are optional for Android Watch device implementations.</p>
1973</div>
1974
1975
1976<p>Device implementations MUST support dynamic video resolution switching within
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]1977the same stream for all VP8, VP9, H.264, and H.265 codecs exposed through the
1978standard Android APIs.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]1979
1980<p>Android device implementations with H.264 decoders, MUST support Baseline
1981Profile Level 3 and the following SD video decoding profiles and SHOULD support
1982the HD decoding profiles. Android Television devices MUST support High Profile
1983Level 4.2 and the HD 1080p decoding profile.</p>
1984<table>
1985 <tr>
1986 <th></th>
1987 <th>SD (Low quality)</th>
1988 <th>SD (High quality)</th>
1989 <th>HD 720p1</th>
1990 <th>HD 1080p1</th>
1991 </tr>
1992 <tr>
1993 <th>Video resolution</th>
1994 <td>320 x 240 px</td>
1995 <td>720 x 480 px</td>
1996 <td>1280 x 720 px</td>
1997 <td>1920 x 1080 px</td>
1998 </tr>
1999 <tr>
2000 <th>Video frame rate</th>
2001 <td>30 fps</td>
2002 <td>30 fps</td>
2003 <td>30 fps / 60 fps2</td>
2004 <td>30 fps / 60 fps2</td>
2005 </tr>
2006 <tr>
2007 <th>Video bitrate</th>
2008 <td>800 Kbps </td>
2009 <td>2 Mbps</td>
2010 <td>8 Mbps</td>
2011 <td>20 Mbps</td>
2012 </tr>
2013</table>
2014
2015
2016<p class="table_footnote">1 Required for Android Television device implementations, but for other device
2017types only when supported by hardware.</p>
2018
2019<p class="table_footnote">2 Required for Android Television device implementations.</p>
2020
2021<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
2022decoding profiles. Android Television devices MUST support the HD 1080p
2023decoding profile. </p>
2024<table>
2025 <tr>
2026 <th></th>
2027 <th>SD (Low quality)</th>
2028 <th>SD (High quality)</th>
2029 <th>HD 720p1</th>
2030 <th>HD 1080p1</th>
2031 </tr>
2032 <tr>
2033 <th>Video resolution</th>
2034 <td>320 x 180 px</td>
2035 <td>640 x 360 px</td>
2036 <td>1280 x 720 px</td>
2037 <td>1920 x 1080 px</td>
2038 </tr>
2039 <tr>
2040 <th>Video frame rate</th>
2041 <td>30 fps</td>
2042 <td>30 fps</td>
2043 <td>30 fps / 60 fps2</td>
2044 <td>30 / 60 fps2</td>
2045 </tr>
2046 <tr>
2047 <th>Video bitrate</th>
2048 <td>800 Kbps </td>
2049 <td>2 Mbps</td>
2050 <td>8 Mbps</td>
2051 <td>20 Mbps</td>
2052 </tr>
2053</table>
2054
2055
2056<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2057devices only when supported by hardware.</p>
2058
2059<p class="table_footnote">2 Required for Android Television device implementations.</p>
2060
2061<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
2062HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2063support the HD 1080p decoding profile and SHOULD support the UHD decoding
2064profile. When the UHD video decoding profile is supported, it MUST support 8
2065bit color depth.</p>
2066<table>
2067 <tr>
2068 <th></th>
2069 <th>SD (Low quality)</th>
2070 <th>SD (High quality)</th>
2071 <th>HD 720p 1</th>
2072 <th>HD 1080p 2</th>
2073 <th>UHD 2</th>
2074 </tr>
2075 <tr>
2076 <th>Video resolution</th>
2077 <td>320 x 180 px</td>
2078 <td>640 x 360 px</td>
2079 <td>1280 x 720 px</td>
2080 <td>1920 x 1080 px</td>
2081 <td>3840 x 2160 px</td>
2082 </tr>
2083 <tr>
2084 <th>Video frame rate</th>
2085 <td>30 fps</td>
2086 <td>30 fps</td>
2087 <td>30 fps</td>
2088 <td>30 fps</td>
2089 <td>30 fps</td>
2090 </tr>
2091 <tr>
2092 <th>Video bitrate</th>
2093 <td>600 Kbps </td>
2094 <td>1.6 Mbps</td>
2095 <td>4 Mbps</td>
2096 <td>10 Mbps</td>
2097 <td>20 Mbps</td>
2098 </tr>
2099</table>
2100
2101
2102<p class="table_footnote">1 Required for Android Television device implementations, but for other type of
2103devices only when supported by hardware.</p>
2104
2105<p class="table_footnote">2 STRONGLY RECOMMENDED for Android Television device implementations when
2106supported by hardware.</p>
2107
2108<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
2109decoding profiles and SHOULD support the HD decoding profiles. Android
2110Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
21111080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2112the UHD decoding profile.</p>
2113<table>
2114 <tr>
2115 <th></th>
2116 <th>SD (Low quality)</th>
2117 <th>SD (High quality)</th>
2118 <th>HD 720p </strong>1 </td>
2119 <th>HD 1080p </strong>1 </td>
2120 <th>UHD </strong>2</td>
2121 </tr>
2122 <tr>
2123 <th>Video resolution</th>
2124 <td>352 x 288 px</td>
2125 <td>640 x 360 px</td>
2126 <td>1280 x 720 px</td>
2127 <td>1920 x 1080 px</td>
2128 <td>3840 x 2160 px</td>
2129 </tr>
2130 <tr>
2131 <th>Video frame rate</th>
2132 <td>30 fps</td>
2133 <td>30 fps</td>
2134 <td>30 fps</td>
2135 <td>30 fps</td>
2136 <td>30 fps</td>
2137 </tr>
2138 <tr>
2139 <th>Video bitrate</th>
2140 <td>600 Kbps </td>
2141 <td>1.6 Mbps</td>
2142 <td>4 Mbps</td>
2143 <td>10 Mbps</td>
2144 <td>20 Mbps</td>
2145 </tr>
2146</table>
2147
2148
2149<p class="table_footnote">1 Required for Android Television device implementation, but for other type of
2150devices only when supported by hardware.</p>
2151
2152<p class="table_footnote">2 Required for Android Television device implementations when supported by
2153hardware.</p>
2154
2155<h2 id="5_4_audio_recording">5.4. Audio Recording</h2>
2156
2157
2158<p>While some of the requirements outlined in this section are stated as SHOULD
2159since Android 4.3, the Compatibility Definition for a future version is planned
2160to 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
2161compatibility when upgraded to the future version.</p>
2162
2163<h3 id="5_4_1_raw_audio_capture">5.4.1. Raw Audio Capture</h3>
2164
2165
2166<p>Device implementations that declare android.hardware.microphone MUST allow
2167capture of raw audio content with the following characteristics:</p>
2168
2169<ul>
2170 <li><strong>Format</strong>: Linear PCM, 16-bit
2171 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
2172 <li><strong>Channels</strong>: Mono
2173</ul>
2174
2175<p>Device implementations that declare android.hardware.microphone SHOULD allow
2176capture of raw audio content with the following characteristics:</p>
2177
2178<ul>
2179 <li><strong>Format</strong>: Linear PCM, 16-bit
2180 <li><strong>Sampling rates</strong>: 22050, 48000
2181 <li><strong>Channels</strong>: Stereo
2182</ul>
2183
2184<h3 id="5_4_2_capture_for_voice_recognition">5.4.2. Capture for Voice Recognition</h3>
2185
2186
2187<p>In addition to the above recording specifications, when an application has
2188started recording an audio stream using the
2189android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
2190
2191<ul>
2192 <li>The device SHOULD exhibit approximately flat amplitude versus frequency
2193characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
2194 <li>Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
2195source at 1000 Hz yields RMS of 2500 for 16-bit samples.
2196 <li>PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
2197dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
2198 <li>Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
2199level at the microphone.
2200 <li>Noise reduction processing, if present, MUST be disabled.
2201 <li>Automatic gain control, if present, MUST be disabled
2202</ul>
2203
2204<p>If the platform supports noise suppression technologies tuned for speech
2205recognition, the effect MUST be controllable from the
2206android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
2207noise suppressor&rsquo;s effect descriptor MUST uniquely identify each implementation
2208of the noise suppression technology.</p>
2209
2210<h3 id="5_4_3_capture_for_rerouting_of_playback">5.4.3. Capture for Rerouting of Playback</h3>
2211
2212
2213<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
2214audio source. Devices that declare android.hardware.audio.output MUST properly
2215implement the REMOTE_SUBMIX audio source so that when an application uses the
2216android.media.AudioRecord API to record from this audio source, it can capture
2217a mix of all audio streams except for the following:</p>
2218
2219<ul>
2220 <li>STREAM_RING
2221 <li>STREAM_ALARM
2222 <li>STREAM_NOTIFICATION
2223</ul>
2224
2225<h2 id="5_5_audio_playback">5.5. Audio Playback</h2>
2226
2227
2228<p>Device implementations that declare android.hardware.audio.output MUST conform
2229to the requirements in this section.</p>
2230
2231<h3 id="5_5_1_raw_audio_playback">5.5.1. Raw Audio Playback</h3>
2232
2233
2234<p>The device MUST allow playback of raw audio content with the following
2235characteristics:</p>
2236
2237<ul>
2238 <li><strong>Format</strong>: Linear PCM, 16-bit</li>
2239 <li><strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100</li>
2240 <li><strong>Channels</strong>: Mono, Stereo</li>
2241</ul>
2242
2243<p>The device SHOULD allow playback of raw audio content with the following
2244characteristics:</p>
2245
2246<ul>
2247 <li><strong>Sampling rates</strong>: 24000, 48000</li>
2248</ul>
2249
2250<h3 id="5_5_2_audio_effects">5.5.2. Audio Effects</h3>
2251
2252
2253<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
2254android.hardware.audio.output:</p>
2255
2256<ul>
2257 <li>MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
2258implementations controllable through the AudioEffect subclasses Equalizer,
2259LoudnessEnhancer.</li>
2260 <li>MUST support the visualizer API implementation, controllable through the
2261Visualizer class.</li>
2262 <li>SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
2263EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
2264controllable through the AudioEffect sub-classes BassBoost,
2265EnvironmentalReverb, PresetReverb, and Virtualizer.</li>
2266</ul>
2267
2268<h3 id="5_5_3_audio_output_volume">5.5.3. Audio Output Volume</h3>
2269
2270
2271<p>Android Television device implementations MUST include support for system
2272Master Volume and digital audio output volume attenuation on supported outputs,
2273except for compressed audio passthrough output (where no audio decoding is done
2274on the device).</p>
2275
2276<h2 id="5_6_audio_latency">5.6. Audio Latency</h2>
2277
2278
2279<p>Audio latency is the time delay as an audio signal passes through a system.
2280Many classes of applications rely on short latencies, to achieve real-time
2281sound effects.</p>
2282
2283<p>For the purposes of this section, use the following definitions:</p>
2284
2285<ul>
2286 <li><strong>output latency</strong>. The interval between when an application writes a frame of PCM-coded data and
2287when the corresponding sound can be heard by an external listener or observed
2288by a transducer.</li>
2289 <li><strong>cold output latency</strong>. The output latency for the first frame, when the audio output system has been
2290idle and powered down prior to the request.</li>
2291 <li><strong>continuous output latency</strong>. The output latency for subsequent frames, after the device is playing audio.</li>
2292 <li><strong>input latency</strong>. The interval between when an external sound is presented to the device and
2293when an application reads the corresponding frame of PCM-coded data.</li>
2294 <li><strong>cold input latency</strong>. The sum of lost input time and the input latency for the first frame, when the
2295audio input system has been idle and powered down prior to the request.</li>
2296 <li><strong>continuous input latency</strong>. The input latency for subsequent frames, while the device is capturing audio.</li>
2297 <li><strong>cold output jitter</strong>. The variance among separate measurements of cold output latency values.</li>
2298 <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]2299 <li><strong>continuous round-trip latency</strong>. The sum of continuous input latency plus continuous output latency plus
2300 one buffer period.
2301 The buffer period term allows processing time for the app and for the app to
2302 mitigate phase difference between input and output streams.
2303 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2304 <li><strong>OpenSL ES PCM buffer queue API</strong>. The set of PCM-related OpenSL ES APIs within Android NDK; see
2305NDK_root/docs/opensles/index.html.</li>
2306</ul>
2307
2308<p>Device implementations that declare android.hardware.audio.output SHOULD meet
2309or exceed these audio output requirements:</p>
2310
2311<ul>
2312 <li>cold output latency of 100 milliseconds or less</li>
2313 <li>continuous output latency of 45 milliseconds or less</li>
2314 <li>minimize the cold output jitter</li>
2315</ul>
2316
2317<p>If a device implementation meets the requirements of this section after any
2318initial calibration when using the OpenSL ES PCM buffer queue API, for
2319continuous output latency and cold output latency over at least one supported
2320audio output device, it MAY report support for low-latency audio, by reporting
2321the feature android.hardware.audio.low_latency via the
2322android.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
2323MUST NOT report support for low-latency audio.</p>
2324
2325<p>Device implementations that include android.hardware.microphone SHOULD meet
2326these input audio requirements:</p>
2327
2328<ul>
2329 <li>cold input latency of 100 milliseconds or less</li>
2330 <li>continuous input latency of 30 milliseconds or less</li>
2331 <li>continuous round-trip latency of 50 milliseconds or less</li>
2332 <li>minimize the cold input jitter</li>
2333</ul>
2334
2335<h2 id="5_7_network_protocols">5.7. Network Protocols</h2>
2336
2337
2338<p>Devices MUST support the media network protocols for audio and video playback
2339as 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>
2340
2341<ul>
2342 <li>RTSP (RTP, SDP)</li>
2343 <li>HTTP(S) progressive streaming</li>
2344 <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>
2345</ul>
2346
2347<h2 id="5_8_secure_media">5.8. Secure Media</h2>
2348
2349
2350<p>Device implementations that support secure video output and are capable of
2351supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
2352implementations that declare support for Display.FLAG_SECURE, if they support a
2353wireless display protocol, MUST secure the link with a cryptographically strong
2354mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
2355if they support a wired external display, the device implementations MUST
2356support HDCP 1.2 or higher. Android Television device implementations MUST
2357support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
2358lower resolutions. The upstream Android open source implementation includes
2359support for wireless (Miracast) and wired (HDMI) displays that satisfies this
2360requirement.</p>
2361
Glenn Kasten87ef61d2015-07-29 09:01:36 -0700[diff] [blame]2362<h2 id="5_9_midi">5.9. Musical Instrument Digital Interface (MIDI)</h2>
2363
2364<p>
2365If a device implementation supports the inter-app MIDI software transport
2366(virtual MIDI devices), and it supports MIDI over
2367<em>all</em> of the following MIDI-capable hardware transports
2368for which it provides generic non-MIDI connectivity, it MAY report
2369support for feature android.software.midi via the
2370android.content.pm.PackageManager class
2371[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2372</p>
2373
2374<p>The MIDI-capable hardware transports are:</p>
2375<ul>
2376 <li>USB host mode (section 7.7 USB)</li>
2377 <li>USB peripheral mode (section 7.7 USB)</li>
2378</ul>
2379
2380<p>
2381Conversely, if the device implementation provides generic non-MIDI connectivity over a particular
2382MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport,
2383it MUST NOT report support for feature android.software.midi.
2384</p>
2385
2386<p>
2387MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)
2388is in trial use status. A device implementation that reports
2389feature android.software.midi, and which provides generic non-MIDI connectivity
2390over Bluetooth LE, SHOULD support MIDI over Bluetooth LE.
2391</p>
2392
Glenn Kasten78eccbd2015-08-12 10:18:22 -0700[diff] [blame]2393<h2 id="5_10_pro_audio">5.10. Professional Audio</h2>
2394
2395<p>
2396If a device implementation meets <em>all</em> of the following requirements,
2397it MAY report support for feature android.hardware.audio.pro via the
2398android.content.pm.PackageManager class
2399[<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].
2400</p>
2401
2402<ul>
2403
2404<li>
2405The device implementation MUST support android.hardware.audio.low_latency
2406</li>
2407
2408<li> The continuous round-trip audio latency, as defined in section 5.6 Audio Latency,
2409MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one
2410supported path.
2411</li>
2412
2413<li>
2414If the device implementation includes a 4 conductor 3.5mm audio jack,
2415the continuous round-trip audio latency MUST be 20 milliseconds or less over the audio jack path,
2416and SHOULD be 10 milliseconds or less over at the audio jack path.
2417</li>
2418
2419<li>
2420The device implementation MUST include a USB port(s) supporting USB host mode and
2421USB peripheral mode.
2422</li>
2423
2424<li>
2425The USB host mode MUST implement the USB audio class and handle concurrent input/output with
2426a USB audio class-compliant peripheral having the following minimum capabilities:
2427<ul>
2428<li>4-channel input</li>
2429<li>4-channel output</li>
2430<li>24-bit depth PCM</li>
2431<li>96 kHz sample rate</li>
2432</ul>
2433</li>
2434
2435<li>
2436If the device includes an HDMI port, the device implementation
2437MUST support output in stereo and 8 channels
2438at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.
2439</li>
2440
2441<li>
2442The device implementation MUST report support for feature android.software.midi.
2443</li>
2444
2445</ul>
2446
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2447<h1 id="6_developer_tools_and_options_compatibility">6. Developer Tools and Options Compatibility</h1>
2448
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2449<h2 id="6_1_developer_tools">6.1. Developer Tools</h2>
2450
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2451<p>Device implementations MUST support the Android Developer Tools provided in the
2452Android SDK. Android compatible devices MUST be compatible with:</p>
2453
2454<ul>
2455 <li><strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]</li>
2456</ul>
2457
2458<p>Device implementations MUST support all adb functions as documented in the
2459Android 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
2460user-accessible mechanism to turn on the Android Debug Bridge. If a device
2461implementation omits USB peripheral mode, it MUST implement the Android Debug
2462Bridge via local-area network (such as Ethernet or 802.11). </p>
2463
2464<p>Android includes support for secure adb. Secure adb enables adb on known
2465authenticated hosts. Device implementations MUST support secure adb.</p>
2466
2467<ul>
2468 <li><strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]</li>
2469</ul>
2470
2471<p>Device implementations MUST support all ddms features as documented in the
2472Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
2473but MUST be supported whenever the user has activated the Android Debug Bridge,
2474as above.</p>
2475
2476<ul>
2477 <li><strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]</li>
2478</ul>
2479
2480<p>Device implementations MUST include the Monkey framework, and make it available
2481for applications to use.</p>
2482
2483<ul>
2484 <li><strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]</li>
2485</ul>
2486
2487<p>Device implementations MUST support systrace tool as documented in the Android
2488SDK. Systrace must be inactive by default, and there MUST be a user-accessible
2489mechanism to turn on Systrace.</p>
2490
2491<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
2492using the standard Android SDK tools, without additional support; however
2493Microsoft Windows systems typically require a driver for new Android devices.
2494(For instance, new vendor IDs and sometimes new device IDs require custom USB
2495drivers for Windows systems.) If a device implementation is unrecognized by the
2496adb tool as provided in the standard Android SDK, device implementers MUST
2497provide Windows drivers allowing developers to connect to the device using the
2498adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
2499Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
2500
2501<h2 id="6_2_developer_options">6.2. Developer Options</h2>
2502
2503
2504<p>Android includes support for developers to configure application
2505development-related settings. Device implementations MUST honor the
2506android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
2507development-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
2508default and enables users to launch Developer Options after pressing seven (7)
2509times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
2510Developer Options. Specifically, device implementations MUST hide Developer
2511Options by default and MUST provide a mechanism to enable Developer Options
2512that is consistent with the upstream Android implementation.</p>
2513
2514<h1 id="7_hardware_compatibility">7. Hardware Compatibility</h1>
2515
2516
2517<p>If a device includes a particular hardware component that has a corresponding
2518API for third-party developers, the device implementation MUST implement that
2519API as described in the Android SDK documentation. If an API in the SDK
2520interacts with a hardware component that is stated to be optional and the
2521device implementation does not possess that component:</p>
2522
2523<ul>
2524 <li>Complete class definitions (as documented by the SDK) for the component APIs
2525MUST still be presented.
2526 <li>The API&rsquo;s behaviors MUST be implemented as no-ops in some reasonable fashion.
2527 <li>API methods MUST return null values where permitted by the SDK documentation.
2528 <li>API methods MUST return no-op implementations of classes where null values are
2529not permitted by the SDK documentation.
2530 <li>API methods MUST NOT throw exceptions not documented by the SDK documentation.
2531</ul>
2532
2533<p>A typical example of a scenario where these requirements apply is the telephony
2534API: even on non-phone devices, these APIs must be implemented as reasonable
2535no-ops.</p>
2536
2537<p>Device implementations MUST consistently report accurate hardware configuration
2538information via the getSystemAvailableFeatures() and hasSystemFeature(String)
2539methods on the android.content.pm.PackageManager class for the same build
2540fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
2541
2542<h2 id="7_1_display_and_graphics">7.1. Display and Graphics</h2>
2543
2544
2545<p>Android includes facilities that automatically adjust application assets and UI
2546layouts appropriately for the device, to ensure that third-party applications
2547run 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
2548this section.</p>
2549
2550<p>The units referenced by the requirements in this section are defined as
2551follows:</p>
2552
2553<ul>
2554 <li><strong>physical diagonal size</strong>. The distance in inches between two opposing corners of the illuminated portion
2555of the display.</li>
2556 <li><strong>dots per inch (dpi)</strong>. The number of pixels encompassed by a linear horizontal or vertical span of
25571&rdquo;. Where dpi values are listed, both horizontal and vertical dpi must fall
2558within the range.</li>
2559 <li><strong>aspect ratio</strong>. The ratio of the pixels of the longer dimension
2560 to the shorter dimension of the screen. For example, a display of 480x854 pixels
2561 would be 854/480 = 1.779, or roughly &ldquo;16:9&rdquo;.</li>
2562 <li><strong>density-independent pixel (dp)</strong> The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
2563dps * (density/160).</li>
2564</ul>
2565
2566<h3 id="7_1_1_screen_configuration">7.1.1. Screen Configuration</h3>
2567
2568
2569<h4 id="7_1_1_1_screen_size">7.1.1.1. Screen Size</h4>
2570
2571<div class="note">
2572<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>
2573</div>
2574
2575<p>The Android UI framework supports a variety of different screen sizes, and
2576allows applications to query the device screen size (aka &ldquo;screen layout") via
2577android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
2578Device implementations MUST report the correct screen size as defined in the
2579Android 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
2580implementations MUST report the correct screen size according to the following
2581logical density-independent pixel (dp) screen dimensions.</p>
2582
2583<ul>
2584 <li>Devices MUST have screen sizes of at least 426 dp x 320 dp (&lsquo;small&rsquo;), unless it
2585is an Android Watch device.</li>
2586 <li>Devices that report screen size &lsquo;normal&rsquo; MUST have screen sizes of at least 480
2587dp x 320 dp.</li>
2588 <li>Devices that report screen size &lsquo;large&rsquo; MUST have screen sizes of at least 640
2589dp x 480 dp.</li>
2590 <li>Devices that report screen size &lsquo;xlarge&rsquo; MUST have screen sizes of at least 960
2591dp x 720 dp.</li>
2592</ul>
2593
2594<p>In addition, </p>
2595
2596<ul>
2597 <li>Android Watch devices MUST have a screen with the physical diagonal size in the
2598range from 1.1 to 2.5 inches.</li>
2599 <li>Other types of Android device implementations, with a physically integrated
2600screen, MUST have a screen at least 2.5 inches in physical diagonal size.</li>
2601</ul>
2602
2603<p>Devices MUST NOT change their reported screen size at any time.</p>
2604
2605<p>Applications optionally indicate which screen sizes they support via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2606&lt;supports-screens&gt; attribute in the AndroidManifest.xml file. Device
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2607implementations MUST correctly honor applications' stated support for small,
2608normal, large, and xlarge screens, as described in the Android SDK
2609documentation.</p>
2610
2611<h4 id="7_1_1_2_screen_aspect_ratio">7.1.1.2. Screen Aspect Ratio</h4>
2612
2613<div class="note">
2614<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
2615</div>
2616
2617
2618<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
261916:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
2620such a device implementation will use a UI_MODE_TYPE_WATCH as the
2621android.content.res.Configuration.uiMode.</p>
2622
2623<h4 id="7_1_1_3_screen_density">7.1.1.3. Screen Density</h4>
2624
2625
2626<p>The Android UI framework defines a set of standard logical densities to help
2627application developers target application resources. Device implementations
2628MUST report only one of the following logical Android framework densities
2629through the android.util.DisplayMetrics APIs, and MUST execute applications at
2630this standard density and MUST NOT change the value at at any time for the
2631default display.</p>
2632
2633<ul>
2634 <li>120 dpi (ldpi)</li>
2635 <li>160 dpi (mdpi)</li>
2636 <li>213 dpi (tvdpi)</li>
2637 <li>240 dpi (hdpi)</li>
2638 <li>280 dpi (280dpi)</li>
2639 <li>320 dpi (xhdpi)</li>
2640 <li>400 dpi (400dpi)</li>
2641 <li>480 dpi (xxhdpi)</li>
2642 <li>560 dpi (560dpi)</li>
2643 <li>640 dpi (xxxhdpi)</li>
2644</ul>
2645
2646<p>Device implementations SHOULD define the standard Android framework density
2647that is numerically closest to the physical density of the screen, unless that
2648logical density pushes the reported screen size below the minimum supported. If
2649the standard Android framework density that is numerically closest to the
2650physical density results in a screen size that is smaller than the smallest
2651supported compatible screen size (320 dp width), device implementations SHOULD
2652report the next lowest standard Android framework density.</p>
2653
2654<h3 id="7_1_2_display_metrics">7.1.2. Display Metrics</h3>
2655
2656
2657<p>Device implementations MUST report correct values for all display metrics
2658defined 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
2659external screen is used as the default display.</p>
2660
2661<h3 id="7_1_3_screen_orientation">7.1.3. Screen Orientation</h3>
2662
2663
2664<p>Devices MUST report which screen orientations they support
2665(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
2666MUST report at least one supported orientation. For example, a device with a
2667fixed orientation landscape screen, such as a television or laptop, SHOULD only
2668report android.hardware.screen.landscape.</p>
2669
2670<p>Devices that report both screen orientations MUST support dynamic orientation
2671by applications to either portrait or landscape screen orientation. That is,
2672the device must respect the application&rsquo;s request for a specific screen
2673orientation. Device implementations MAY select either portrait or landscape
2674orientation as the default.</p>
2675
2676<p>Devices MUST report the correct value for the device&rsquo;s current orientation,
2677whenever queried via the android.content.res.Configuration.orientation,
2678android.view.Display.getOrientation(), or other APIs.</p>
2679
2680<p>Devices MUST NOT change the reported screen size or density when changing
2681orientation.</p>
2682
2683<h3 id="7_1_4_2d_and_3d_graphics_acceleration">7.1.4. 2D and 3D Graphics Acceleration</h3>
2684
2685
2686<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
2687detailed in the Android SDK documentations. Device implementations SHOULD
2688support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
2689implementations MUST also support Android RenderScript, as detailed in the
2690Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
2691
2692<p>Device implementations MUST also correctly identify themselves as supporting
2693OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
2694
2695<ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]2696 <li>The managed APIs (such as via the GLES10.getString() method) MUST report support
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]2697for OpenGL ES 1.0 and OpenGL ES 2.0.</li>
2698 <li>The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
2699libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
2700ES 2.0.</li>
2701 <li>Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
2702support the corresponding managed APIs and include support for native C/C++
2703APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
2704libGLESv2.so MUST export the corresponding function symbols in addition to the
2705OpenGL ES 2.0 function symbols.</li>
2706</ul>
2707
2708<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
2709interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
2710and the ASTC texture compression format. Android device implementations MAY
2711support this extension pack, and&mdash;only if fully implemented&mdash;MUST identify the
2712support through the android.hardware.opengles.aep feature flag.</p>
2713
2714<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
2715However, device implementations MUST report via the OpenGL ES managed and
2716native APIs all extension strings that they do support, and conversely MUST NOT
2717report extension strings that they do not support.</p>
2718
2719<p>Note that Android includes support for applications to optionally specify that
2720they require specific OpenGL texture compression formats. These formats are
2721typically vendor-specific. Device implementations are not required by Android
2722to implement any specific texture compression format. However, they SHOULD
2723accurately report any texture compression formats that they do support, via the
2724getString() method in the OpenGL API.</p>
2725
2726<p>Android includes a mechanism for applications to declare that they want to
2727enable hardware acceleration for 2D graphics at the Application, Activity,
2728Window, or View level through the use of a manifest tag
2729android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2730
2731<p>Device implementations MUST enable hardware acceleration by default, and MUST
2732disable hardware acceleration if the developer so requests by setting
2733android:hardwareAccelerated="false&rdquo; or disabling hardware acceleration directly
2734through the Android View APIs.</p>
2735
2736<p>In addition, device implementations MUST exhibit behavior consistent with the
2737Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
2738
2739<p>Android includes a TextureView object that lets developers directly integrate
2740hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
2741Device implementations MUST support the TextureView API, and MUST exhibit
2742consistent behavior with the upstream Android implementation.</p>
2743
2744<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
2745that indicates whether the EGLConfig supports rendering to an ANativeWindow
2746that records images to a video. Device implementations MUST support
2747EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
2748
2749<h3 id="7_1_5_legacy_application_compatibility_mode">7.1.5. Legacy Application Compatibility Mode</h3>
2750
2751
2752<p>Android specifies a &ldquo;compatibility mode&rdquo; in which the framework operates in a
2753'normal' screen size equivalent (320dp width) mode for the benefit of legacy
2754applications not developed for old versions of Android that pre-date
2755screen-size independence.</p>
2756
2757<ul>
2758<li>Android Automotive does not support legacy compatibility mode.</li>
2759<li>All other device implementations MUST include support for legacy application
2760compatibility mode as implemented by the upstream Android open source code. That
2761is, device implementations MUST NOT alter the triggers or thresholds at which
2762compatibility mode is activated, and MUST NOT alter the behavior of the
2763compatibility mode itself.</li>
2764</ul>
2765
2766<h3 id="7_1_6_screen_technology">7.1.6. Screen Technology</h3>
2767
2768
2769<p>The Android platform includes APIs that allow applications to render rich
2770graphics to the display. Devices MUST support all of these APIs as defined by
2771the Android SDK unless specifically allowed in this document. </p>
2772
2773<ul>
2774 <li>Devices MUST support displays capable of rendering 16-bit color graphics and
2775SHOULD support displays capable of 24-bit color graphics.</li>
2776 <li>Devices MUST support displays capable of rendering animations.</li>
2777 <li>The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
2778and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
277915% tolerance.</li>
2780</ul>
2781
2782<h3 id="7_1_7_external_displays">7.1.7. Secondary Displays</h3>
2783
2784
2785<p>Android includes support for secondary display to enable media sharing
2786capabilities and developer APIs for accessing external displays. If a device
2787supports an external display either via a wired, wireless, or an embedded
2788additional display connection then the device implementation MUST implement the
2789display 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>
2790
2791<h2 id="7_2_input_devices">7.2. Input Devices</h2>
2792
2793<p>Devices MUST support a touchscreen or meet the requirements listed in 7.2.2
2794for non-touch navigation.</p>
2795
2796<h3 id="7_2_1_keyboard">7.2.1. Keyboard</h3>
2797
2798<div class="note">
2799<p>Android Watch and Android Automotive implementations MAY implement a soft
2800keyboard. All other device implementations MUST implement a soft keyboard and:</p>
2801</div>
2802
2803
2804<p>Device implementations:</p>
2805
2806<ul>
2807 <li>MUST include support for the Input Management Framework (which allows
2808third-party developers to create Input Method Editors&mdash;i.e. soft keyboard) as
2809detailed at <a href="http://developer.android.com">http://developer.android.com</a>.</li>
2810 <li>MUST provide at least one soft keyboard implementation (regardless of whether a
2811hard keyboard is present) except for Android Watch devices where the screen
2812size makes it less reasonable to have a soft keyboard.</li>
2813 <li>MAY include additional soft keyboard implementations.</li>
2814 <li>MAY include a hardware keyboard.</li>
2815 <li>MUST NOT include a hardware keyboard that does not match one of the formats
2816specified 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>
2817</ul>
2818
2819<h3 id="7_2_2_non-touch_navigation">7.2.2. Non-touch Navigation</h3>
2820
2821<div class="note">
2822<p>Android Television devices MUST support D-pad.</p>
2823</div>
2824
2825<p>Device implementations:</p>
2826
2827<ul>
2828 <li>MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
2829device implementation is not an Android Television device.</li>
2830 <li>MUST report the correct value for android.content.res.Configuration.navigation
2831[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>].</li>
2832 <li>MUST provide a reasonable alternative user interface mechanism for the
2833selection and editing of text, compatible with Input Management Engines. The
2834upstream Android open source implementation includes a selection mechanism
2835suitable for use with devices that lack non-touch navigation inputs.</li>
2836</ul>
2837
2838<h3 id="7_2_3_navigation_keys">7.2.3. Navigation Keys</h3>
2839
2840<div class="note">
2841<p>The availability and visibility requirement of the Home, Recents, and Back
2842functions differ between device types as described in this section.</p>
2843</div>
2844
2845<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
2846KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
2847navigation paradigm and therefore:</p>
2848
2849<ul>
2850 <li>Android Handheld device implementations MUST provide the Home, Recents, and
2851Back functions.</li>
2852 <li>Android Television device implementations MUST provide the Home and Back
2853functions.</li>
2854 <li>Android Watch device implementations MUST have the Home function available to
2855the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.</li>
2856 <li>Android Automotive implementations MUST provide the Home function and MAY
2857provide Back and Recent functions.</li>
2858 <li>All other types of device implementations MUST provide the Home and Back
2859functions.</li>
2860</ul>
2861
2862<p>These functions MAY be implemented via dedicated physical buttons (such as
2863mechanical or capacitive touch buttons), or MAY be implemented using dedicated
2864software keys on a distinct portion of the screen, gestures, touch panel, etc.
2865Android supports both implementations. All of these functions MUST be
2866accessible with a single action (e.g. tap, double-click or gesture) when
2867visible.</p>
2868
2869<p>Recents function, if provided, MUST have a visible button or icon unless hidden
2870together with other navigation functions in full-screen mode. This does not
2871apply to devices upgrading from earlier Android versions that have physical
2872buttons for navigation and no recents key.</p>
2873
2874<p> The Home and Back functions, if provided, MUST each have a visible button or
2875icon unless hidden together with other navigation functions in full-screen mode
2876or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
2877
2878<p>The Menu function is deprecated in favor of action bar since Android 4.0.
2879Therefore the new device implementations shipping with Android ANDROID_VERSION and later MUST NOT
2880implement a dedicated physical button for the Menu function. Older device
2881implementations SHOULD NOT implement a dedicated physical button for the Menu
2882function, but if the physical Menu button is implemented and the device is
2883running applications with targetSdkVersion > 10, the device implementation:</p>
2884
2885<ul>
2886 <li>MUST display the action overflow button on the action bar when it is visible
2887and the resulting action overflow menu popup is not empty. For a device
2888implementation launched before Android 4.4 but upgrading to Android ANDROID_VERSION, this
2889is RECOMMENDED.</li>
2890 <li>MUST NOT modify the position of the action overflow popup displayed by
2891selecting the overflow button in the action bar.</li>
2892 <li>MAY render the action overflow popup at a modified position on the screen when
2893it is displayed by selecting the physical menu button.</li>
2894</ul>
2895
2896<p>For backwards compatibility, device implementations MUST make the Menu function
2897available to applications when targetSdkVersion is less than 10, either by a physical
2898button, a software key, or gestures. This Menu function should be presented
2899unless hidden together with other navigation functions.</p>
2900
2901<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
2902the Assist action available to the user at all times when running applications.
2903The Assist action SHOULD be implemented as a long-press on the Home button or a
2904swipe-up gesture on the software Home key. This function MAY be implemented via
2905another physical button, software key, or gesture, but MUST be accessible with
2906a single action (e.g. tap, double-click, or gesture) when other navigation keys
2907are visible.</p>
2908
2909<p>Device implementations MAY use a distinct portion of the screen to display the
2910navigation keys, but if so, MUST meet these requirements:</p>
2911
2912<ul>
2913 <li>Device implementation navigation keys MUST use a distinct portion of the
2914screen, not available to applications, and MUST NOT obscure or otherwise
2915interfere with the portion of the screen available to applications.</li>
2916 <li>Device implementations MUST make available a portion of the display to
2917applications that meets the requirements defined in <a href="#7_1_1_screen_configuration">section 7.1.1</a>.</li>
2918 <li>Device implementations MUST display the navigation keys when applications do
2919not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.</li>
2920 <li>Device implementations MUST present the navigation keys in an unobtrusive &ldquo;low
2921profile&rdquo; (eg. dimmed) mode when applications specify
2922SYSTEM_UI_FLAG_LOW_PROFILE.</li>
2923 <li>Device implementations MUST hide the navigation keys when applications specify
2924SYSTEM_UI_FLAG_HIDE_NAVIGATION.</li>
2925</ul>
2926
2927<h3 id="7_2_4_touchscreen_input">7.2.4. Touchscreen Input</h3>
2928
2929<div class="note">
2930<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
2931</div>
2932
2933
2934<p>Device implementations SHOULD have a pointer input system of some kind (either
2935mouse-like or touch). However, if a device implementation does not support a
2936pointer input system, it MUST NOT report the android.hardware.touchscreen or
2937android.hardware.faketouch feature constant. Device implementations that do
2938include a pointer input system:</p>
2939
2940<ul>
2941 <li>SHOULD support fully independently tracked pointers, if the device input system
2942supports multiple pointers.</li>
2943 <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>
2944</ul>
2945
2946<p>Android includes support for a variety of touchscreens, touch pads, and fake
2947touch input devices. Touchscreen based device implementations are associated
2948with 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
2949screen. Since the user is directly touching the screen, the system does not
2950require any additional affordances to indicate the objects being manipulated.
2951In contrast, a fake touch interface provides a user input system that
2952approximates a subset of touchscreen capabilities. For example, a mouse or
2953remote control that drives an on-screen cursor approximates touch, but requires
2954the user to first point or focus then click. Numerous input devices like the
2955mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
2956trackpad can support fake touch interactions. Android includes the feature
2957constant android.hardware.faketouch, which corresponds to a high-fidelity
2958non-touch (pointer-based) input device such as a mouse or trackpad that can
2959adequately emulate touch-based input (including basic gesture support), and
2960indicates that the device supports an emulated subset of touchscreen
2961functionality. Device implementations that declare the fake touch feature MUST
2962meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2963
2964<p>Device implementations MUST report the correct feature corresponding to the
2965type of input used. Device implementations that include a touchscreen
2966(single-touch or better) MUST report the platform feature constant
2967android.hardware.touchscreen. Device implementations that report the platform
2968feature constant android.hardware.touchscreen MUST also report the platform
2969feature constant android.hardware.faketouch. Device implementations that do not
2970include a touchscreen (and rely on a pointer device only) MUST NOT report any
2971touchscreen feature, and MUST report only android.hardware.faketouch if they
2972meet the fake touch requirements in <a href="#7_2_5_fake_touch_input">section 7.2.5</a>.</p>
2973
2974<h3 id="7_2_5_fake_touch_input">7.2.5. Fake Touch Input</h3>
2975
2976
2977<p>Device implementations that declare support for android.hardware.faketouch:</p>
2978
2979<ul>
2980 <li>MUST report the absolute X and Y screen positions of the pointer location and
2981display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2982 <li>MUST report touch event with the action code that specifies the state change
2983that 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>
2984 <li>MUST support pointer down and up on an object on the screen, which allows users
2985to emulate tap on an object on the screen.</li>
2986 <li>MUST support pointer down, pointer up, pointer down then pointer up in the same
2987place on an object on the screen within a time threshold, which allows users to
2988emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>].</li>
2989 <li>MUST support pointer down on an arbitrary point on the screen, pointer move to
2990any other arbitrary point on the screen, followed by a pointer up, which allows
2991users to emulate a touch drag.</li>
2992 <li>MUST support pointer down then allow users to quickly move the object to a
2993different position on the screen and then pointer up on the screen, which
2994allows users to fling an object on the screen.</li>
2995</ul>
2996
2997<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
2998MUST meet the requirements for faketouch above, and MUST also support distinct
2999tracking of two or more independent pointer inputs.</p>
3000
3001<h3 id="7_2_6_game_controller_support">7.2.6. Game Controller Support</h3>
3002
3003
3004<p>Android Television device implementations MUST support button mappings for game
3005controllers as listed below. The upstream Android implementation includes
3006implementation for game controllers that satisfies this requirement. </p>
3007
3008<h4 id="7_2_6_1_button_mappings">7.2.6.1. Button Mappings</h4>
3009
3010
3011<p>Android Television device implementations MUST support the following key
3012mappings:</p>
3013<table>
3014 <tr>
3015 <th>Button</th>
3016 <th>HID Usage</strong><sup>2</sup></td>
3017 <th>Android Button</th>
3018 </tr>
3019 <tr>
3020 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a><sup>1</sup></td>
3021 <td>0x09 0x0001</td>
3022 <td>KEYCODE_BUTTON_A (96)</td>
3023 </tr>
3024 <tr>
3025 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a><sup>1</sup></td>
3026 <td>0x09 0x0002</td>
3027 <td>KEYCODE_BUTTON_B (97)</td>
3028 </tr>
3029 <tr>
3030 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a><sup>1</sup></td>
3031 <td>0x09 0x0004</td>
3032 <td>KEYCODE_BUTTON_X (99)</td>
3033 </tr>
3034 <tr>
3035 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a><sup>1</sup></td>
3036 <td>0x09 0x0005</td>
3037 <td>KEYCODE_BUTTON_Y (100)</td>
3038 </tr>
3039 <tr>
3040 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a><sup>1</sup></p>
3041
3042<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]3043 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3044 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a><sup>4</sup></td>
3045 </tr>
3046 <tr>
3047 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3048
3049<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]3050 <td>0x01 0x0039<sup>3</sup></td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3051 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X</a><sup>4</sup></td>
3052 </tr>
3053 <tr>
3054 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a><sup>1</sup></td>
3055 <td>0x09 0x0007</td>
3056 <td>KEYCODE_BUTTON_L1 (102)</td>
3057 </tr>
3058 <tr>
3059 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a><sup>1</sup></td>
3060 <td>0x09 0x0008</td>
3061 <td>KEYCODE_BUTTON_R1 (103)</td>
3062 </tr>
3063 <tr>
3064 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a><sup>1</sup></td>
3065 <td>0x09 0x000E</td>
3066 <td>KEYCODE_BUTTON_THUMBL (106)</td>
3067 </tr>
3068 <tr>
3069 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a><sup>1</sup></td>
3070 <td>0x09 0x000F</td>
3071 <td>KEYCODE_BUTTON_THUMBR (107)</td>
3072 </tr>
3073 <tr>
3074 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a><sup>1</sup></td>
3075 <td>0x0c 0x0223</td>
3076 <td>KEYCODE_HOME (3)</td>
3077 </tr>
3078 <tr>
3079 <td><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a><sup>1</sup></td>
3080 <td>0x0c 0x0224</td>
3081 <td>KEYCODE_BACK (4)</td>
3082 </tr>
3083</table>
3084
3085
3086<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3087
3088<p class="table_footnote">2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3089
3090<p class="table_footnote">3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3091Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3092Report Size of 4. The logical value is defined to be the clockwise rotation
3093away from the vertical axis; for example, a logical value of 0 represents no
3094rotation and the up button being pressed, while a logical value of 1 represents
3095a rotation of 45 degrees and both the up and left keys being pressed.</p>
3096
3097<p class="table_footnote">4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3098
3099<table>
3100 <tr>
3101 <th>Analog Controls</strong><sup>1</sup></td>
3102 <th>HID Usage</th>
3103 <th>Android Button</th>
3104 </tr>
3105 <tr>
3106 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></td>
3107 <td>0x02 0x00C5</td>
3108 <td>AXIS_LTRIGGER </td>
3109 </tr>
3110 <tr>
3111 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></td>
3112 <td>0x02 0x00C4</td>
3113 <td>AXIS_RTRIGGER </td>
3114 </tr>
3115 <tr>
3116 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></td>
3117 <td>0x01 0x0030</p>
3118
3119<p>0x01 0x0031</td>
3120 <td>AXIS_X</p>
3121
3122<p>AXIS_Y</td>
3123 </tr>
3124 <tr>
3125 <td><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></td>
3126 <td>0x01 0x0032</p>
3127
3128<p>0x01 0x0035</td>
3129 <td>AXIS_Z</p>
3130
3131<p>AXIS_RZ</td>
3132 </tr>
3133</table>
3134
3135
3136<p class="table_footnote">1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3137
3138<h3 id="7_2_7_remote_control">7.2.7. Remote Control</h3>
3139
3140
3141<p>Android Television device implementations SHOULD provide a remote control to
3142allow users to access the TV interface. The remote control MAY be a physical
3143remote or can be a software-based remote that is accessible from a mobile phone
3144or tablet. The remote control MUST meet the requirements defined below.</p>
3145
3146<ul>
3147 <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>
3148 <li><strong>Navigation</strong>. All Android Television remotes MUST include Back, Home, and Select buttons and
3149support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].</li>
3150</ul>
3151
3152<h2 id="7_3_sensors">7.3. Sensors</h2>
3153
3154
3155<p>Android includes APIs for accessing a variety of sensor types. Devices
3156implementations generally MAY omit these sensors, as provided for in the
3157following subsections. If a device includes a particular sensor type that has a
3158corresponding API for third-party developers, the device implementation MUST
3159implement that API as described in the Android SDK documentation and the
3160Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>]. For example, device implementations:</p>
3161
3162<ul>
3163 <li>MUST accurately report the presence or absence of sensors per the
3164android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>.</li>
3165 <li>MUST return an accurate list of supported sensors via the
3166SensorManager.getSensorList() and similar methods.</li>
3167 <li>MUST behave reasonably for all other sensor APIs (for example, by returning
3168true or false as appropriate when applications attempt to register listeners,
3169not calling sensor listeners when the corresponding sensors are not present;
3170etc.).</li>
3171 <li>MUST report all sensor measurements using the relevant International System of
3172Units (metric) values for each sensor type as defined in the Android SDK
3173documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3174 <li>SHOULD report the event time in nanoseconds as defined in the Android SDK
3175documentation, representing the time the event happened and synchronized with
3176the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
3177are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
3178platform releases where this might become a REQUIRED component. The
3179synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].</li>
3180</ul>
3181
3182<p>The list above is not comprehensive; the documented behavior of the Android SDK
3183and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors/">Resources, 73</a>] is to be considered authoritative.</p>
3184
3185<p>Some sensor types are composite, meaning they can be derived from data provided
3186by one or more other sensors. (Examples include the orientation sensor, and the
3187linear acceleration sensor.) Device implementations SHOULD implement these
3188sensor types, when they include the prerequisite physical sensors as described
3189in [<a href="https://source.android.com/devices/sensors/sensor-types.html">Resources, 76</a>].
3190If a device implementation includes a composite sensor it MUST implement the
3191sensor as described in the Android Open Source documentation on composite
3192sensors [<a href="https://source.android.com/devices/sensors/sensor-types.html#composite_sensor_type_summary">Resources, 76</a>].</p>
3193
3194<p>Some Android sensors support a &ldquo;continuous&rdquo; trigger mode, which returns data
3195continuously [<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
3196sensor, device implementations MUST continuously provide periodic data samples
3197that SHOULD have a jitter below 3%, where jitter is defined as the standard
3198deviation of the difference of the reported timestamp values between
3199consecutive events.</p>
3200
3201<p>Note that the device implementations MUST ensure that the sensor event stream
3202MUST NOT prevent the device CPU from entering a suspend state or waking up from
3203a suspend state.</p>
3204
3205<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
3206exceed the sum of the individual sensor&rsquo;s reported power consumption.</p>
3207
3208<h3 id="7_3_1_accelerometer">7.3.1. Accelerometer</h3>
3209
3210
3211<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
3212devices and Android Watch devices are strongly encouraged to include this
3213sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
3214
3215<ul>
3216 <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>
3217 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3218 Android Watch devices as such devices have a stricter power constraint and
3219 100 Hz for all other device types.</li>
3220 <li>SHOULD report events up to at least 200 Hz.</li>
3221 <li>MUST comply with the Android sensor coordinate system as detailed in the
3222Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3223 <li>MUST be capable of measuring from freefall up to four times the gravity (4g) or
3224more on any axis.</li>
3225 <li>MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
3226least 16-bits.</li>
3227 <li>SHOULD be calibrated while in use if the characteristics changes over the life
3228cycle and compensated, and preserve the compensation parameters between device
3229reboots.</li>
3230 <li>SHOULD be temperature compensated.</li>
3231 <li>MUST have a standard deviation no greater than 0.05 m/s^, where the standard
3232deviation should be calculated on a per axis basis on samples collected over a
3233period of at least 3 seconds at the fastest sampling rate.</li>
3234 <li>SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
3235TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
3236Android 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
3237sensors are implemented, the sum of their power consumption MUST always be less
3238than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
3239dynamic or static condition.</li>
3240 <li>If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
3241TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3242TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3243are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3244 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
3245and a magnetometer sensor is also included.</li>
3246</ul>
3247
3248<h3 id="7_3_2_magnetometer">7.3.2. Magnetometer</h3>
3249
3250
3251<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
3252device does include a 3-axis magnetometer, it:</p>
3253
3254<ul>
3255 <li>MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
3256TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
3257strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.</li>
3258 <li>MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
3259report events up to at least 50 Hz.</li>
3260 <li>MUST comply with the Android sensor coordinate system as detailed in the
3261Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>].</li>
3262 <li>MUST be capable of measuring between -900 &micro;T and +900 &micro;T on each axis before
3263saturating.</li>
3264 <li>MUST have a hard iron offset value less than 700 &micro;T and SHOULD have a value
3265below 200 &micro;T, by placing the magnetometer far from dynamic (current-induced)
3266and static (magnet-induced) magnetic fields.</li>
3267 <li>MUST have a resolution equal or denser than 0.6 &micro;T and SHOULD have a resolution
3268equal or denser than 0.2 &micro;.</li>
3269 <li>SHOULD be temperature compensated.</li>
3270 <li>MUST support online calibration and compensation of the hard iron bias, and
3271preserve the compensation parameters between device reboots.</li>
3272 <li>MUST have the soft iron compensation applied&mdash;the calibration can be done either
3273while in use or during the production of the device.</li>
3274 <li>SHOULD have a standard deviation, calculated on a per axis basis on samples
3275collected over a period of at least 3 seconds at the fastest sampling rate, no
3276greater than 0.5 &micro;T.</li>
3277 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3278sensor and a gyroscope sensor is also included.</li>
3279 <li>MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
3280sensor is also implemented. However if implemented, it MUST consume less than
328110 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
3282mode at 10 Hz.</li>
3283</ul>
3284
3285<h3 id="7_3_3_gps">7.3.3. GPS</h3>
3286
3287
3288<p>Device implementations SHOULD include a GPS receiver. If a device
3289implementation does include a GPS receiver, it SHOULD include some form of&ldquo;assisted GPS&rdquo; technique to minimize GPS lock-on time.</p>
3290
3291<h3 id="7_3_4_gyroscope">7.3.4. Gyroscope</h3>
3292
3293
3294<p>Device implementations SHOULD include a gyroscope (angular change sensor).
3295Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
3296also included. If a device implementation includes a gyroscope, it:</p>
3297
3298<ul>
3299 <li>MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
3300TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
3301strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.</li>
3302 <li>MUST be capable of measuring orientation changes up to 1,000 degrees per second.</li>
3303 <li>MUST be able to report events up to a frequency of at least 50 Hz for
3304 Android Watch devices as such devices have a stricter power constraint and
3305 100 Hz for all other device types.</li>
3306 <li>SHOULD report events up to at least 200 Hz.</li>
3307 <li>MUST have a resolution of 12-bits or more and SHOULD have a resolution of
330816-bits or more.</li>
3309 <li>MUST be temperature compensated.</li>
3310 <li>MUST be calibrated and compensated while in use, and preserve the compensation
3311parameters between device reboots.</li>
3312 <li>MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
3313or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
3314be constrained by this value. In other words, if you measure the variance of
3315the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.</li>
3316 <li>SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
3317sensor and a magnetometer sensor is also included.</li>
3318 <li>If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
3319TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
3320TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
3321are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.</li>
3322</ul>
3323
3324<h3 id="7_3_5_barometer">7.3.5. Barometer</h3>
3325
3326
3327<p>Device implementations SHOULD include a barometer (ambient air pressure
3328sensor). If a device implementation includes a barometer, it:</p>
3329
3330<ul>
3331 <li>MUST implement and report TYPE_PRESSURE sensor.</li>
3332 <li>MUST be able to deliver events at 5 Hz or greater.</li>
3333 <li>MUST have adequate precision to enable estimating altitude.</li>
3334 <li>MUST be temperature compensated.</li>
3335</ul>
3336
3337<h3 id="7_3_6_thermometer">7.3.6. Thermometer</h3>
3338
3339
3340<p>Device implementations MAY include an ambient thermometer (temperature sensor).
3341If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
3342measure the ambient (room) temperature in degrees Celsius.</p>
3343
3344<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
3345present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
3346temperature of the device CPU, and it MUST NOT measure any other temperature.
3347Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
3348
3349<h3 id="7_3_7_photometer">7.3.7. Photometer</h3>
3350
3351
3352<p>Device implementations MAY include a photometer (ambient light sensor).</p>
3353
3354<h3 id="7_3_8_proximity_sensor">7.3.8. Proximity Sensor</h3>
3355
3356
3357<p>Device implementations MAY include a proximity sensor. Devices that can make a
3358voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
3359SHOULD include a proximity sensor. If a device implementation does include a
3360proximity sensor, it:</p>
3361
3362<ul>
3363 <li>MUST measure the proximity of an object in the same direction as the screen.
3364That is, the proximity sensor MUST be oriented to detect objects close to the
3365screen, as the primary intent of this sensor type is to detect a phone in use
3366by the user. If a device implementation includes a proximity sensor with any
3367other orientation, it MUST NOT be accessible through this API.</li>
3368 <li>MUST have 1-bit of accuracy or more.</li>
3369</ul>
3370
3371<h2 id="7_4_data_connectivity">7.4. Data Connectivity</h2>
3372
3373
3374<h3 id="7_4_1_telephony">7.4.1. Telephony</h3>
3375
3376
3377<p>&ldquo;Telephony&rdquo; as used by the Android APIs and this document refers specifically
3378to hardware related to placing voice calls and sending SMS messages via a GSM
3379or CDMA network. While these voice calls may or may not be packet-switched,
3380they are for the purposes of Android considered independent of any data
3381connectivity that may be implemented using the same network. In other words,
3382the Android &ldquo;telephony&rdquo; functionality and APIs refer specifically to voice
3383calls and SMS. For instance, device implementations that cannot place calls or
3384send/receive SMS messages MUST NOT report the android.hardware.telephony
3385feature or any subfeatures, regardless of whether they use a cellular network
3386for data connectivity.</p>
3387
3388<p>Android MAY be used on devices that do not include telephony hardware. That is,
3389Android is compatible with devices that are not phones. However, if a device
3390implementation does include GSM or CDMA telephony, it MUST implement full
3391support for the API for that technology. Device implementations that do not
3392include telephony hardware MUST implement the full APIs as no-ops.</p>
3393
3394<h3 id="7_4_2_ieee_802_11_wi-fi">7.4.2. IEEE 802.11 (Wi-Fi)</h3>
3395
3396<div class="note">
3397<p>Android Television device implementations MUST include Wi-Fi support.</p>
3398</div>
3399
3400
3401<p>Android Television device implementations MUST include support for one or more
3402forms of 802.11 (b/g/a/n, etc.) and other types of Android device
3403implementation SHOULD include support for one or more forms of 802.11. If a
3404device implementation does include support for 802.11 and exposes the
3405functionality to a third-party application, it MUST implement the corresponding
3406Android API and:</p>
3407
3408<ul>
3409 <li>MUST report the hardware feature flag android.hardware.wifi.</li>
3410 <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>
3411 <li>MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
3412(224.0.0.251) at any time of operation including when the screen is not in an
3413active state.</li>
3414</ul>
3415
3416<h4 id="7_4_2_1_wi-fi_direct">7.4.2.1. Wi-Fi Direct</h4>
3417
3418
3419<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
3420peer-to-peer). If a device implementation does include support for Wi-Fi
3421Direct, it MUST implement the corresponding Android API as described in the SDK
3422documentation [<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>
3423
3424<ul>
3425 <li>MUST report the hardware feature android.hardware.wifi.direct.</li>
3426 <li>MUST support regular Wi-Fi operation.</li>
3427 <li>SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation.</li>
3428</ul>
3429
3430<h4 id="7_4_2_2_wi-fi_tunneled_direct_link_setup">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
3431
3432<div class="note">
3433<p>Android Television device implementations MUST include support for Wi-Fi
3434Tunneled Direct Link Setup (TDLS).</p>
3435</div>
3436
3437
3438<p>Android Television device implementations MUST include support for Wi-Fi
3439Tunneled Direct Link Setup (TDLS) and other types of Android device
3440implementations SHOULD include support for Wi-Fi TDLS as described in the
3441Android 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
3442by the WiFiManager API, the device:</p>
3443
3444<ul>
3445 <li>SHOULD use TDLS only when it is possible AND beneficial.</li>
3446 <li>SHOULD have some heuristic and NOT use TDLS when its performance might be worse
3447than going through the Wi-Fi access point.</li>
3448</ul>
3449
3450<h3 id="7_4_3_bluetooth">7.4.3. Bluetooth</h3>
3451
3452<div class="note">
3453<p>Android Watch and Automotive implementations MUST support Bluetooth. Android
3454Television implementations MUST support Bluetooth and Bluetooth LE.</p>
3455</div>
3456
3457
3458<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
3459Energy MUST declare the relevant platform features (android.hardware.bluetooth
3460and android.hardware.bluetooth_le respectively) and implement the platform
3461APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
3462as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
3463device implementations MUST support Bluetooth and Bluetooth LE. </p>
3464
3465<p>Device implementations including support for Bluetooth Low Energy:</p>
3466
3467<ul>
3468 <li>MUST declare the hardware feature android.hardware.bluetooth_le.</li>
3469 <li>MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
3470described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>].</li>
3471 <li>SHOULD support offloading of the filtering logic to the bluetooth chipset when
3472implementing 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
3473android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method.</li>
3474 <li>SHOULD support offloading of the batched scanning to the bluetooth chipset, but
3475if not supported, MUST report &lsquo;false&rsquo; whenever queried via the
3476android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.</li>
3477 <li>SHOULD support multi advertisement with at least 4 slots, but if not supported,
3478MUST report &lsquo;false&rsquo; whenever queried via the
3479android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method.</li>
3480</ul>
3481
3482<h3 id="7_4_4_near-field_communications">7.4.4. Near-Field Communications</h3>
3483
3484
3485<p>Device implementations SHOULD include a transceiver and related hardware for
3486Near-Field Communications (NFC). If a device implementation does include NFC
3487hardware and plans to make it available to third-party apps, then it:</p>
3488
3489<ul>
3490 <li>MUST report the android.hardware.nfc feature from the
3491android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>].</li>
3492 <li>MUST be capable of reading and writing NDEF messages via the following NFC
3493standards:
3494 <ul>
3495 <li>MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
3496Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
3497following NFC standards:
3498 <ul>
3499 <li>NfcA (ISO14443-3A)</li>
3500 <li>NfcB (ISO14443-3B)</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3501 <li>NfcF (JIS X 6319-4)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3502 <li>IsoDep (ISO 14443-4)</li>
3503 <li>NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)</li>
3504 </ul>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3505 <li>MUST be capable of reading and writing NDEF messages as well as raw
3506 data via the following NFC standards:</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3507 <ul>
3508 <li>NfcV (ISO 15693)</li>
3509 </ul></li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3510 <li>SHOULD be capable of reading the barcode and URL (if encoded) of
3511 Thinfilm NFC Barcode
3512 [<a href="http://developer.android.com/reference/android/nfc/tech/NfcBarcode.html">Resources, XX</a>] products.
3513 </li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3514 <li>MUST be capable of transmitting and receiving data via the following
3515peer-to-peer standards and protocols:
3516 <ul>
3517 <li>ISO 18092</li>
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3518 <li>LLCP 1.2 (defined by the NFC Forum)</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3519 <li>SDP 1.0 (defined by the NFC Forum)</li>
3520 <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>
3521 <li>SNEP 1.0 (defined by the NFC Forum)</li>
3522 </ul></li>
3523 <li>MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
3524 <ul>
3525 <li>MUST implement the SNEP default server. Valid NDEF messages received by the
3526default SNEP server MUST be dispatched to applications using the
3527android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
3528MUST NOT disable dispatch of incoming NDEF message.</li>
3529 <li>MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
3530settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>].</li>
3531 <li>MUST implement the NPP server. Messages received by the NPP server MUST be
3532processed the same way as the SNEP default server.</li>
3533 <li>MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
3534default SNEP server when Android Beam is enabled. If no default SNEP server is
3535found then the client MUST attempt to send to an NPP server.</li>
3536 <li>MUST allow foreground activities to set the outbound P2P NDEF message using
3537android.nfc.NfcAdapter.setNdefPushMessage, and
3538android.nfc.NfcAdapter.setNdefPushMessageCallback, and
3539android.nfc.NfcAdapter.enableForegroundNdefPush.</li>
3540 <li>SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
3541sending outbound P2P NDEF messages.</li>
3542 <li>SHOULD enable Android Beam by default and MUST be able to send and receive
3543using Android Beam, even when another proprietary NFC P2p mode is turned on.</li>
3544 <li>MUST support NFC Connection handover to Bluetooth when the device supports
3545Bluetooth Object Push Profile. Device implementations MUST support connection
3546handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
3547implementing 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
3548LLCP service with service name &ldquo;urn:nfc:sn:handover&rdquo; for exchanging the
3549handover request/select records over NFC, and it MUST use the Bluetooth Object
3550Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
3551remain compatible with Android 4.1 devices), the implementation SHOULD still
3552accept SNEP GET requests for exchanging the handover request/select records
3553over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
3554for performing connection handover.</li>
3555 </ul></li>
3556 <li>MUST poll for all supported technologies while in NFC discovery mode.</li>
3557 <li>SHOULD be in NFC discovery mode while the device is awake with the screen
3558active and the lock-screen unlocked.</li>
3559</ul>
3560</ul>
3561
3562<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
3563Forum specifications cited above.)</p>
3564
3565<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
3566device implementation does include an NFC controller chipset capable of HCE and
3567Application ID (AID) routing, then it:</p>
3568
3569<ul>
3570 <li>MUST report the android.hardware.nfc.hce feature constant.</li>
3571 <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>
3572</ul>
3573
3574<p>Additionally, device implementations MAY include reader/writer support for the
3575following MIFARE technologies.</p>
3576
3577<ul>
3578 <li>MIFARE Classic</li>
3579 <li>MIFARE Ultralight</li>
3580 <li>NDEF on MIFARE Classic</li>
3581</ul>
3582
3583<p>Note that Android includes APIs for these MIFARE types. If a device
3584implementation supports MIFARE in the reader/writer role, it:</p>
3585
3586<ul>
3587 <li>MUST implement the corresponding Android APIs as documented by the Android SDK.</li>
3588 <li>MUST report the feature com.nxp.mifare from the
Martijn Coenen048f4aa2015-09-17 14:24:55 +0200[diff] [blame]3589android.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
3590as a constant in the android.content.pm.PackageManager class.</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3591 <li>MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
3592feature unless it also implements general NFC support as described in this
3593section.</li>
3594</ul>
3595
3596<p>If a device implementation does not include NFC hardware, it MUST NOT declare
3597the android.hardware.nfc feature from the
3598android.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>
3599
3600<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
3601protocol-independent data representation format, device implementations MUST
3602implement these APIs even if they do not include support for NFC or declare the
3603android.hardware.nfc feature.</p>
3604
3605<h3 id="7_4_5_minimum_network_capability">7.4.5. Minimum Network Capability</h3>
3606
3607
3608<p>Device implementations MUST include support for one or more forms of data
3609networking. Specifically, device implementations MUST include support for at
3610least one data standard capable of 200Kbit/sec or greater. Examples of
3611technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
3612Ethernet, Bluetooth PAN, etc.</p>
3613
3614<p>Device implementations where a physical networking standard (such as Ethernet)
3615is the primary data connection SHOULD also include support for at least one
3616common wireless data standard, such as 802.11 (Wi-Fi).</p>
3617
3618<p>Devices MAY implement more than one form of data connectivity.</p>
3619
3620<h3 id="7_4_6_sync_settings">7.4.6. Sync Settings</h3>
3621
3622
3623<p>Device implementations MUST have the master auto-sync setting on by default so
3624that the method getMasterSyncAutomatically() returns &ldquo;true&rdquo; [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
3625
3626<h2 id="7_5_cameras">7.5. Cameras</h2>
3627
3628
3629<p>Device implementations SHOULD include a rear-facing camera and MAY include a
3630front-facing camera. A rear-facing camera is a camera located on the side of
3631the device opposite the display; that is, it images scenes on the far side of
3632the device, like a traditional camera. A front-facing camera is a camera
3633located on the same side of the device as the display; that is, a camera
3634typically used to image the user, such as for video conferencing and similar
3635applications.</p>
3636
3637<p>If a device implementation includes at least one camera, it SHOULD be possible
3638for an application to simultaneously allocate 3 bitmaps equal to the size of
3639the images produced by the largest-resolution camera sensor on the device.</p>
3640
3641<h3 id="7_5_1_rear-facing_camera">7.5.1. Rear-Facing Camera</h3>
3642
3643
3644<p>Device implementations SHOULD include a rear-facing camera. If a device
3645implementation includes at least one rear-facing camera, it:</p>
3646
3647<ul>
3648 <li>MUST report the feature flag android.hardware.camera and
3649android.hardware.camera.any.</li>
3650 <li>MUST have a resolution of at least 2 megapixels.</li>
3651 <li>SHOULD have either hardware auto-focus or software auto-focus implemented in
3652the camera driver (transparent to application software).</li>
3653 <li>MAY have fixed-focus or EDOF (extended depth of field) hardware.</li>
3654 <li>MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
3655lit while an android.hardware.Camera.PreviewCallback instance has been
3656registered on a Camera preview surface, unless the application has explicitly
3657enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
3658of a Camera.Parameters object. Note that this constraint does not apply to the
3659device&rsquo;s built-in system camera application, but only to third-party
3660applications using Camera.PreviewCallback.</li>
3661</ul>
3662
3663<h3 id="7_5_2_front-facing_camera">7.5.2. Front-Facing Camera</h3>
3664
3665
3666<p>Device implementations MAY include a front-facing camera. If a device
3667implementation includes at least one front-facing camera, it:</p>
3668
3669<ul>
3670 <li>MUST report the feature flag android.hardware.camera.any and
3671android.hardware.camera.front.</li>
3672 <li>MUST have a resolution of at least VGA (640x480 pixels).</li>
3673 <li>MUST NOT use a front-facing camera as the default for the Camera API. The
3674camera API in Android has specific support for front-facing cameras and device
3675implementations MUST NOT configure the API to to treat a front-facing camera as
3676the default rear-facing camera, even if it is the only camera on the device.</li>
3677 <li>MAY include features (such as auto-focus, flash, etc.) available to rear-facing
3678cameras as described in <a href="#7_5_1_rear-facing_camera">section 7.5.1</a>.</li>
3679 <li>MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
3680CameraPreview, as follows:
3681 <ul>
3682 <li>If the device implementation is capable of being rotated by user (such as
3683automatically via an accelerometer or manually via user input), the camera
3684preview MUST be mirrored horizontally relative to the device&rsquo;s current
3685orientation.</li>
3686 <li>If the current application has explicitly requested that the Camera display be
3687rotated 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
3688orientation specified by the application.</li>
3689 <li>Otherwise, the preview MUST be mirrored along the device&rsquo;s default horizontal
3690axis.</li>
3691 </ul></li>
3692 <li>MUST mirror the image displayed by the postview in the same manner as the
3693camera preview image stream. If the device implementation does not support
3694postview, this requirement obviously does not apply.</li>
3695 <li>MUST NOT mirror the final captured still image or video streams returned to
3696application callbacks or committed to media storage.</li>
3697</ul>
3698
3699<h3 id="7_5_3_external_camera">7.5.3. External Camera</h3>
3700
3701
3702<p>Device implementations with USB host mode MAY include support for an external
3703camera that connects to the USB port. If a device includes support for an
3704external camera, it:</p>
3705
3706<ul>
3707 <li>MUST declare the platform feature android.hardware.camera.external and
3708android.hardware camera.any.</li>
3709 <li>MUST support USB Video Class (UVC 1.0 or higher).</li>
3710 <li>MAY support multiple cameras.</li>
3711</ul>
3712
3713<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
3714high-quality unencoded streams (i.e. raw or independently compressed picture
3715streams). Camera-based video encoding MAY be supported. If so, a simultaneous
3716unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
3717device implementation.</p>
3718
3719<h3 id="7_5_4_camera_api_behavior">7.5.4. Camera API Behavior</h3>
3720
3721
3722<p>Android includes two API packages to access the camera, the newer
3723android.hardware.camera2 API expose lower-level camera control to the app,
3724including efficient zero-copy burst/streaming flows and per-frame controls of
3725exposure, gain, white balance gains, color conversion, denoising, sharpening,
3726and more.</p>
3727
3728<p>The older API package, android.hardware.Camera, is marked as deprecated in
3729Android 5.0 but as it should still be available for apps to use Android device
3730implementations MUST ensure the continued support of the API as described in
3731this section and in the Android SDK.</p>
3732
3733<p>Device implementations MUST implement the following behaviors for the
3734camera-related APIs, for all available cameras:</p>
3735
3736<ul>
3737 <li>If an application has never called
3738android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
3739use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
3740application callbacks.</li>
3741 <li>If an application registers an android.hardware.Camera.PreviewCallback instance
3742and the system calls the onPreviewFrame() method when the preview format is
3743YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
3744be in the NV21 encoding format. That is, NV21 MUST be the default.</li>
3745 <li>For android.hardware.Camera, device implementations MUST support the YV12
3746format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
3747camera previews for both front- and rear-facing cameras. (The hardware video
3748encoder and camera may use any native pixel format, but the device
3749implementation MUST support conversion to YV12.)</li>
3750 <li>For android.hardware.camera2, device implementations must support the
3751android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
3752formats as outputs through the android.media.ImageReader API.</li>
3753</ul>
3754
3755<p>Device implementations MUST still implement the full Camera API included in the
3756Android 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
3757capabilities. For instance, cameras that lack autofocus MUST still call any
3758registered android.hardware.Camera.AutoFocusCallback instances (even though
3759this has no relevance to a non-autofocus camera.) Note that this does apply to
3760front-facing cameras; for instance, even though most front-facing cameras do
3761not support autofocus, the API callbacks must still be &ldquo;faked&rdquo; as described.</p>
3762
3763<p>Device implementations MUST recognize and honor each parameter name defined as
3764a constant on the android.hardware.Camera.Parameters class, if the underlying
3765hardware supports the feature. If the device hardware does not support a
3766feature, the API must behave as documented. Conversely, device implementations
3767MUST NOT honor or recognize string constants passed to the
3768android.hardware.Camera.setParameters() method other than those documented as
3769constants on the android.hardware.Camera.Parameters. That is, device
3770implementations MUST support all standard Camera parameters if the hardware
3771allows, and MUST NOT support custom Camera parameter types. For instance,
3772device implementations that support image capture using high dynamic range
3773(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>
3774
3775<p>Because not all device implementations can fully support all the features of
3776the android.hardware.camera2 API, device implementations MUST report the proper
3777level of support with the android.info.supportedHardwareLevel property as
3778described 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>
3779
3780<p>Device implementations MUST also declare its Individual camera capabilities of
3781android.hardware.camera2 via the android.request.availableCapabilities property
3782and 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>
3783
3784<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
3785whenever a new picture is taken by the camera and the entry of the picture has
3786been added to the media store.</p>
3787
3788<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
3789whenever a new video is recorded by the camera and the entry of the picture has
3790been added to the media store.</p>
3791
3792<h3 id="7_5_5_camera_orientation">7.5.5. Camera Orientation</h3>
3793
3794
3795<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
3796long dimension of the camera aligns with the screen&rsquo;s long dimension. That is,
3797when the device is held in the landscape orientation, cameras MUST capture
3798images in the landscape orientation. This applies regardless of the device&rsquo;s
3799natural orientation; that is, it applies to landscape-primary devices as well
3800as portrait-primary devices.</p>
3801
3802<h2 id="7_6_memory_and_storage">7.6. Memory and Storage</h2>
3803
3804
3805<h3 id="7_6_1_minimum_memory_and_storage">7.6.1. Minimum Memory and Storage</h3>
3806
3807<div class="note">
3808<p>Android Television devices MUST have at least 5GB of non-volatile storage
3809available for application private data.</p>
3810</div>
3811
3812
3813<p>The memory available to the kernel and userspace on device implementations MUST
3814be at least equal or larger than the minimum values specified by the following
3815table. (See <a href="#7_1_1_screen_configuration">section 7.1.1</a> for screen size and density definitions.)</p>
3816<table>
3817 <tr>
3818 <th>Density and screen size</th>
3819 <th>32-bit device</th>
3820 <th>64-bit device</th>
3821 </tr>
3822 <tr>
3823 <td>Android Watch devices (due to smaller screens)</td>
3824 <td>416MB</td>
3825 <td>Not applicable</td>
3826 </tr>
3827 <tr>
3828 <td><ul>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3829 <li class="table_list">280dpi or lower on small/normal screens</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3830 <li class="table_list">mdpi or lower on large screens</li>
3831 <li class="table_list">ldpi or lower on extra large screens</li>
3832 </ul></td>
3833 <td>424MB</td>
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]3834 <td>704MB</td>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]3835 </tr>
3836 <tr>
3837 <td><ul>
3838 <li class="table_list">xhdpi or higher on small/normal screens</li>
3839 <li class="table_list">hdpi or higher on large screens</li>
3840 <li class="table_list">mdpi or higher on extra large screens</li></ul></td>
3841 <td>512MB</td>
3842 <td>832MB</td>
3843 </tr>
3844 <tr>
3845 <td><ul>
3846 <li class="table_list">400dpi or higher on small/normal screens</li>
3847 <li class="table_list">xhdpi or higher on large screens</li>
3848 <li class="table_list">tvdpi or higher on extra large screens</li></ul></td>
3849 <td>896MB</td>
3850 <td>1280MB</td>
3851 </tr>
3852 <tr>
3853 <td><ul>
3854 <li class="table_list">560dpi or higher on small/normal screens</li>
3855 <li class="table_list">400dpi or higher on large screens</li>
3856 <li class="table_list">xhdpi or higher on extra large screens</li></ul></td>
3857 <td>1344MB</td>
3858 <td>1824MB</td>
3859 </tr>
3860</table>
3861
3862
3863<p>The minimum memory values MUST be in addition to any memory space already
3864dedicated to hardware components such as radio, video, and so on that is not
3865under the kernel&rsquo;s control.</p>
3866
3867<p>Device implementations with less than 512MB of memory available to the kernel
3868and userspace, unless an Android Watch, MUST return the value "true" for
3869ActivityManager.isLowRamDevice().</p>
3870
3871<p>Android Television devices MUST have at least 5GB and other device
3872implementations MUST have at least 1.5GB of non-volatile storage available for
3873application private data. That is, the /data partition MUST be at least 5GB for
3874Android Television devices and at least 1.5GB for other device implementations.
3875Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
3876they will be able to upgrade to the future platform releases.</p>
3877
3878<p>The Android APIs include a Download Manager that applications MAY use to
3879download 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
3880downloading individual files of at least 100MB in size to the default &ldquo;cache"
3881location.</p>
3882
3883<h3 id="7_6_2_application_shared_storage">7.6.2. Application Shared Storage</h3>
3884
3885
3886<p>Device implementations MUST offer shared storage for applications also often
3887referred as &ldquo;shared external storage&rdquo;. </p>
3888
3889<p>Device implementations MUST be configured with shared storage mounted by
3890default, &ldquo;out of the box&rdquo;. If the shared storage is not mounted on the Linux
3891path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
3892to the actual mount point.</p>
3893
3894<p>Device implementations MAY have hardware for user-accessible removable storage,
3895such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
3896shared storage requirement, the device implementation:</p>
3897
3898<ul>
3899 <li>MUST implement a toast or pop-up user interface warning the user when there is
3900no SD card.</li>
3901 <li>MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
3902and other material available at time of purchase that the SD card has to be
3903separately purchased.</li>
3904 <li>MUST mount the SD card by default.</li>
3905</ul>
3906
3907<p>Alternatively, device implementations MAY allocate internal (non-removable)
3908storage as shared storage for apps as included in the upstream Android Open
3909Source Project; device implementations SHOULD use this configuration and
3910software implementation. If a device implementation uses internal
3911(non-removable) storage to satisfy the shared storage requirement, that storage
3912MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
3913symbolic link to the physical location if it is mounted elsewhere).</p>
3914
3915<p>Device implementations MUST enforce as documented the
3916android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
3917Shared storage MUST otherwise be writable by any application that obtains that
3918permission.</p>
3919
3920<p>Device implementations that include multiple shared storage paths (such as both
3921an SD card slot and shared internal storage) MUST NOT allow Android
3922applications to write to the secondary external storage, except for their
3923package-specific directories on the secondary external storage, but SHOULD
3924expose content from both storage paths transparently through Android&rsquo;s media
3925scanner service and android.provider.MediaStore.</p>
3926
3927<p>Regardless of the form of shared storage used, if the device implementation
3928has a USB port with USB peripheral mode support, it MUST provide some mechanism
3929to access the contents of shared storage from a host computer. Device
3930implementations MAY use USB mass storage, but SHOULD use Media Transfer Protocol
3931to satisfy this requirement. If the device implementation supports Media
3932Transfer Protocol, it:</p>
3933
3934<ul>
3935 <li>SHOULD be compatible with the reference Android MTP host, Android File Transfer
3936[<a href="http://www.android.com/filetransfer">Resources, 96</a>].</li>
3937 <li>SHOULD report a USB device class of 0x00.</li>
3938 <li>SHOULD report a USB interface name of 'MTP'.</li>
3939</ul>
3940
3941<h2 id="7_7_usb">7.7. USB</h2>
3942
3943
3944<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
3945USB host mode.</p>
3946
3947<p>If a device implementation includes a USB port supporting peripheral mode:</p>
3948
3949<ul>
3950 <li>The port MUST be connectable to a USB host that has a standard type-A or type
3951-C USB port.</li>
3952 <li>The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
3953new 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>
3954 <li>The port SHOULD be centered in the middle of an edge. Device implementations
3955SHOULD either locate the port on the bottom of the device (according to natural
3956orientation) or enable software screen rotation for all apps (including home
3957screen), so that the display draws correctly when the device is oriented with
3958the 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>
3959 <li>It MUST allow a USB host connected with the Android device to access the
3960contents of the shared storage volume using either USB mass storage or Media
3961Transfer Protocol.</li>
3962 <li>It SHOULD implement the Android Open Accessory (AOA) API and specification as
3963documented in the Android SDK documentation, and if it is an Android Handheld
3964device it MUST implement the AOA API. Device implementations implementing the
3965AOA specification:
3966 <ul>
3967 <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>
3968 <li>MUST implement the USB audio class as documented in the Android SDK
3969documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3970 </ul></li>
3971 <li>It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
3972as 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>
3973 <li>The value of iSerialNumber in USB standard device descriptor MUST be equal to
3974the value of android.os.Build.SERIAL.</li>
3975</ul>
3976
3977<p>If a device implementation includes a USB port supporting host mode, it:</p>
3978
3979<ul>
3980 <li>SHOULD use a type-C USB port, if the device implementation supports USB 3.1.</li>
3981 <li>MAY use a non-standard port form factor, but if so MUST ship with a cable or
3982cables adapting the port to a standard type-A or type-C USB port.</li>
3983 <li>MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
3984adapting the port to a standard type-A or type-C USB port.</li>
3985 <li>is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
3986documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>].</li>
3987 <li>MUST implement the Android USB host API as documented in the Android SDK, and
3988MUST 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>
3989 <li>SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
3990as 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>
3991</ul>
3992
3993<h2 id="7_8_audio">7.8. Audio</h2>
3994
3995
3996<h3 id="7_8_1_microphone">7.8.1. Microphone</h3>
3997
3998<div class="note">
3999<p>Android Handheld, Watch, and Automotive implementations MUST include a
4000microphone.</p>
4001</div>
4002
4003
4004<p>Device implementations MAY omit a microphone. However, if a device
4005implementation omits a microphone, it MUST NOT report the
4006android.hardware.microphone feature constant, and MUST implement the audio
4007recording API at least as no-ops, per <a href="#7_hardware_compatibility">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4008
4009<ul>
4010 <li>MUST report the android.hardware.microphone feature constant
4011 <li>MUST meet the audio recording requirements in <a href="#5_4_audio_recording">section 5.4</a>
4012 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>
4013</ul>
4014
4015<h3 id="7_8_2_audio_output">7.8.2. Audio Output</h3>
4016
4017<div class="note">
4018<p>Android Watch devices MAY include an audio output.</p>
4019</div>
4020
4021<p>Device implementations including a speaker or with an audio/multimedia output
4022port for an audio output peripheral as a headset or an external speaker:</p>
4023
4024<ul>
4025 <li>MUST report the android.hardware.audio.output feature constant.</li>
4026 <li>MUST meet the audio playback requirements in <a href="#5_5_audio_playback">section 5.5</a>.</li>
4027 <li>MUST meet the audio latency requirements in <a href="#5_6_audio_latency">section 5.6</a>.</li>
4028</ul>
4029
4030<p>Conversely, if a device implementation does not include a speaker or audio
4031output port, it MUST NOT report the android.hardware.audio output feature, and
4032MUST implement the Audio Output related APIs as no-ops at least. </p>
4033
4034<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4035other types of Android device implementations MUST have an audio output and
4036declare android.hardware.audio.output.</p>
4037
4038<h4 id="7_8_2_1_analog_audio_ports">7.8.2.1. Analog Audio Ports</h4>
4039
4040
4041<p>In order to be compatible with the headsets and other audio accessories using
4042the 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
4043one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4044implementation has a 4 conductor 3.5mm audio jack, it:</p>
4045
4046<ul>
4047 <li>MUST support audio playback to stereo headphones and stereo headsets with a
4048microphone, and SHOULD support audio recording from stereo headsets with a
4049microphone.</li>
4050 <li>MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4051audio plugs with the OMTP pin-out order.</li>
4052 <li>MUST support the detection of microphone on the plugged in audio accessory, if
4053the device implementation supports a microphone, and broadcast the
4054android.intent.action.HEADSET_PLUG with the extra value microphone set as 1.</li>
4055 <li>SHOULD support the detection and mapping to the keycodes for the following 3
4056ranges of equivalent impedance between the microphone and ground conductors on
4057the audio plug:
4058 <ul>
4059 <li><strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK</li>
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4060 <li><strong>210&#45;290 Ohm</strong>: KEYCODE_VOLUME_UP</li>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4061 <li><strong>360&#45;680 Ohm</strong>: KEYCODE_VOLUME_DOWN</li>
4062 </ul></li>
4063 <li>SHOULD support the detection and mapping to the keycode for the following range
4064of equivalent impedance between the microphone and ground conductors on the
4065audio plug:
4066 <ul>
4067 <li><strong>110&#45;180 Ohm: </strong>KEYCODE_VOICE_ASSIST</li>
4068 </ul></li>
4069 <li>MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
4070contacts on plug are touching their relevant segments on the jack.</li>
4071 <li>MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
4072speaker impedance.</li>
4073 <li>MUST have a microphone bias voltage between 1.8V ~ 2.9V.</li>
4074</ul>
4075
4076<h1 id="8_performance_compatibility">8. Performance Compatibility</h1>
4077
4078
4079<p>Some minimum performance criterias are critical to the user experience and
4080impacts the baseline assumptions developers would have when developing an app.
4081Android Watch devices SHOULD and other type of device implementations MUST meet
4082the following criteria:</p>
4083
4084<h2 id="8_1_user_experience_consistency">8.1. User Experience Consistency</h2>
4085
4086
4087<p>Device implementations MUST provide a smooth user interface by ensuring a
4088consistent frame rate and response times for applications and games. Device
4089implementations MUST meet the following requirements: </p>
4090
4091<ul>
4092 <li><strong>Consistent frame latency</strong>. Inconsistent frame latency or a delay to render frames MUST NOT happen more
4093often than 5 frames in a second, and SHOULD be below 1 frames in a second.</li>
4094 <li><strong>User interface latency</strong>. Device implementations MUST ensure low latency user experience by scrolling a
4095list of 10K list entries as defined by the Android Compatibility Test Suite
4096(CTS) in less than 36 secs.</li>
4097 <li><strong>Task switching</strong>. When multiple applications have been launched, re-launching an already-running
4098application after it has been launched MUST take less than 1 second.</li>
4099</ul>
4100
4101<h2 id="8_2_file_i_o_access_performance">8.2. File I/O Access Performance</h2>
4102
4103
4104<p>Device implementations MUST ensure internal storage file access performance consistency for read
4105and write operations. </p>
4106
4107<ul>
4108 <li><strong>Sequential write</strong>. Device implementations MUST ensure a sequential write performance of at least 5MB/s
4109for a 256MB file using 10MB write buffer.</li>
4110 <li><strong>Random write</strong>. Device implementations MUST ensure a random write performance of at least 0.5MB/s for a
4111256MB file using 4KB write buffer.</li>
4112 <li><strong>Sequential read</strong>. Device implementations MUST ensure a sequential read performance of at least 15MB/s for
4113a 256MB file using 10MB write buffer.</li>
4114 <li><strong>Random read</strong>. Device implementations MUST ensure a random read performance of at least 3.5MB/s for a
4115256MB file using 4KB write buffer.</li>
4116</ul>
4117
4118<h1 id="9_security_model_compatibility">9. Security Model Compatibility</h1>
4119
4120
4121<p>Device implementations MUST implement a security model consistent with the
4122Android platform security model as defined in Security and Permissions
4123reference 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
4124installation of self-signed applications without requiring any additional
4125permissions/certificates from any third parties/authorities. Specifically,
4126compatible devices MUST support the security mechanisms described in the follow
4127subsections.</p>
4128
4129<h2 id="9_1_permissions">9.1. Permissions</h2>
4130
4131
4132<p>Device implementations MUST support the Android permissions model as defined in
4133the 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
4134described in the SDK documentation; no permissions may be omitted, altered, or
4135ignored. Implementations MAY add additional permissions, provided the new
4136permission ID strings are not in the android.* namespace.</p>
4137
Svetoslav4bbf7402015-09-11 14:45:48 -0700[diff] [blame]4138<p>Permissions with a protection level of dangerous are runtime permissions. Applications
4139with targetSdkVersion > 22 request them at runtime. The system MUST show a dedicated UI for the
4140user to decide whether to grant the requested runtime permissions and also provide a UI for the
4141user to manage runtime permissions. On the system there MUST be one and only one
4142implementation of both the UI for the user to accept runtime permissions and the UI for
4143the user to manage runtime permissions.</p>
4144
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4145<h2 id="9_2_uid_and_process_isolation">9.2. UID and Process Isolation</h2>
4146
4147
4148<p>Device implementations MUST support the Android application sandbox model, in
4149which each application runs as a unique Unixstyle UID and in a separate
4150process. Device implementations MUST support running multiple applications as
4151the same Linux user ID, provided that the applications are properly signed and
4152constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4153
4154<h2 id="9_3_filesystem_permissions">9.3. Filesystem Permissions</h2>
4155
4156
4157<p>Device implementations MUST support the Android file access permissions model
4158as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
4159
4160<h2 id="9_4_alternate_execution_environments">9.4. Alternate Execution Environments</h2>
4161
4162
4163<p>Device implementations MAY include runtime environments that execute
4164applications using some other software or technology than the Dalvik Executable
4165Format or native code. However, such alternate execution environments MUST NOT
4166compromise the Android security model or the security of installed Android
4167applications, as described in this section.</p>
4168
4169<p>Alternate runtimes MUST themselves be Android applications, and abide by the
4170standard Android security model, as described elsewhere in <a href="#9_security_model_compatibility">section 9</a>.</p>
4171
4172<p>Alternate runtimes MUST NOT be granted access to resources protected by
4173permissions not requested in the runtime&rsquo;s AndroidManifest.xml file via the
Unsuk Jung2e62f9a2015-07-16 23:01:44 -0700[diff] [blame]4174&lt;uses-permission&gt; mechanism.</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4175
4176<p>Alternate runtimes MUST NOT permit applications to make use of features
4177protected by Android permissions restricted to system applications.</p>
4178
4179<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
4180alternate runtimes:</p>
4181
4182<ul>
4183 <li>SHOULD install apps via the PackageManager into separate Android sandboxes (
4184Linux user IDs, etc.).</li>
4185 <li>MAY provide a single Android sandbox shared by all applications using the
4186alternate runtime.</li>
4187 <li>and installed applications using an alternate runtime, MUST NOT reuse the
4188sandbox of any other app installed on the device, except through the standard
4189Android mechanisms of shared user ID and signing certificate.</li>
4190 <li>MUST NOT launch with, grant, or be granted access to the sandboxes
4191corresponding to other Android applications.</li>
4192 <li>MUST NOT be launched with, be granted, or grant to other applications any
4193privileges of the superuser (root), or of any other user ID.</li>
4194</ul>
4195
4196<p>The .apk files of alternate runtimes MAY be included in the system image of a
4197device implementation, but MUST be signed with a key distinct from the key used
4198to sign other applications included with the device implementation.</p>
4199
4200<p>When installing applications, alternate runtimes MUST obtain user consent for
4201the Android permissions used by the application. If an application needs to
4202make use of a device resource for which there is a corresponding Android
4203permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
4204user that the application will be able to access that resource. If the runtime
4205environment does not record application capabilities in this manner, the
4206runtime environment MUST list all permissions held by the runtime itself when
4207installing any application using that runtime.</p>
4208
4209<h2 id="9_5_multi-user_support">9.5. Multi-User Support</h2>
4210
4211<div class="note">
4212<p>This feature is optional for all device types.</p>
4213</div>
4214
4215
4216<p>Android includes support for multiple users and provides support for full user
4217isolation [<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
4218the following requirements related to multi-user support [<a href="http://source.android.com/devices/storage/">Resources, 104</a>]:</p>
4219
4220<ul>
4221 <li>Device implementations that do not declare the android.hardware.telephony
4222feature flag MUST support restricted profiles, a feature that allows device
4223owners to manage additional users and their capabilities on the device. With
4224restricted profiles, device owners can quickly set up separate environments for
4225additional users to work in, with the ability to manage finer-grained
4226restrictions in the apps that are available in those environments.</li>
4227 <li>Conversely device implementations that declare the android.hardware.telephony
4228feature flag MUST NOT support restricted profiles but MUST align with the AOSP
4229implementation of controls to enable /disable other users from accessing the
4230voice calls and SMS.</li>
4231 <li>Device implementations MUST, for each user, implement a security model
4232consistent with the Android platform security model as defined in Security and
4233Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</li>
4234 <li>Device implementations MAY support creating users and managed profiles via the
4235android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
4236platform feature flag android.software.managed_users.
4237 <li>Device implementations that declare the feature flag
4238android.software.managed_users MUST use the upstream AOSP icon badge to
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4239represent the managed applications and other badge UI elements like Recents &amp;
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4240Notifications.</li>
4241 <li>Each user instance on an Android device MUST have separate and isolated
4242external storage directories. Device implementations MAY store multiple users'
4243data on the same volume or filesystem. However, the device implementation MUST
4244ensure that applications owned by and running on behalf a given user cannot
4245list, read, or write to data owned by any other user. Note that removable
4246media, such as SD card slots, can allow one user to access another&rsquo;s data by
4247means of a host PC. For this reason, device implementations that use removable
4248media for the external storage APIs MUST encrypt the contents of the SD card if
4249multiuser is enabled using a key stored only on non-removable media accessible
4250only to the system. As this will make the media unreadable by a host PC, device
4251implementations will be required to switch to MTP or a similar system to
4252provide host PCs with access to the current user&rsquo;s data. Accordingly, device
4253implementations MAY but SHOULD NOT enable multi-user if they use removable
4254media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.</li>
4255</ul>
4256
4257<h2 id="9_6_premium_sms_warning">9.6. Premium SMS Warning</h2>
4258
4259
4260<p>Android includes support for warning users of any outgoing premium SMS message
4261[<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
4262carrier that may incur a charge to the user. Device implementations that
4263declare support for android.hardware.telephony MUST warn users before sending a
4264SMS message to numbers identified by regular expressions defined in
4265/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
4266Project provides an implementation that satisfies this requirement.</p>
4267
4268<h2 id="9_7_kernel_security_features">9.7. Kernel Security Features</h2>
4269
4270
4271<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
4272(SELinux) mandatory access control (MAC) system and other security features in
4273the Linux kernel. SELinux or any other security features, if implemented below
4274the Android framework:</p>
4275
4276<ul>
4277 <li>MUST maintain compatibility with existing applications.</li>
4278 <li>MUST NOT have a visible user interface when a security violation is detected
4279and successfully blocked, but MAY have a visible user interface when an
4280unblocked security violation occurs resulting in a successful exploit.</li>
4281 <li>SHOULD NOT be user or developer configurable.</li>
4282</ul>
4283
4284<p>If any API for configuration of policy is exposed to an application that can
4285affect another application (such as a Device Administration API), the API MUST
4286NOT allow configurations that break compatibility.</p>
4287
4288<p>Devices MUST implement SELinux or an equivalent mandatory access control system
4289if using a kernel other than Linux and meet the following requirements, which
4290are satisfied by the reference implementation in the upstream Android Open
4291Source Project.</p>
4292
4293<p>Device implementations:</p>
4294
4295<ul>
4296 <li>MUST support a SELinux policy that allows the SELinux mode to be set on a
4297per-domain basis, and MUST configure all domains in enforcing mode. No
4298permissive mode domains are allowed, including domains specific to a
4299device/vendor.</li>
4300 <li>SHOULD load policy from /sepolicy file on the device.</li>
4301 <li>MUST NOT modify, omit, or replace the neverallow rules present within the
4302sepolicy file provided in the upstream Android Open Source Project (AOSP) and
4303the policy MUST compile with all neverallow present, for both AOSP SELinux
4304domains as well as device/vendor specific domains.</li>
4305 <li>MUST support dynamic updates of the SELinux policy file without requiring a
4306system image update.</li>
4307</ul>
4308
4309<p>Device implementations SHOULD retain the default SELinux policy provided in the
4310upstream Android Open Source Project, until they have first audited their
4311additions to the SELinux policy. Device implementations MUST be compatible with
4312the upstream Android Open Source Project.</p>
4313
4314<h2 id="9_8_privacy">9.8. Privacy</h2>
4315
4316<p>If the device implements functionality in the system that captures the contents
4317displayed on the screen and/or records the audio stream played on the device,
4318it MUST continuously notify the user whenever this functionality is enabled and
4319actively capturing/recording.</p>
4320
4321<p>If a device implementation has a mechanism that routes network data traffic
4322through a proxy server or VPN gateway by default (for example, preloading a VPN
4323service with android.permission.CONTROL_VPN granted), the device implementation
4324MUST ask for the user's consent before enabling that mechanism.</p>
4325
4326<h2 id="9_9_full-disk_encryption">9.9. Full-Disk Encryption</h2>
4327
4328<div class="note">
4329<p>Optional for Android device implementations without a lock screen.</p>
4330</div>
4331
4332
4333<p>If the device implementation supports a lock screen with PIN (numeric) or
4334PASSWORD (alphanumeric), the device MUST support full-disk encryption of the
4335application private data (/data partition), as well
4336as the SD card partition if it is a permanent, non-removable part of the device
4337[<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
4338be enabled all the time after the user has completed the out-of-box experience.
4339While this requirement is stated as SHOULD for this version of the Android
4340platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
4341Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
4342for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
4343be written to storage at any time without being encrypted. Other than when in
4344active use, the encryption key SHOULD be AES encrypted with the lockscreen
4345passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
4346If the user has not specified a lockscreen passcode or has disabled use of the
4347passcode for encryption, the system SHOULD use a default passcode to wrap the
4348encryption key. If the device provides a hardware-backed keystore, the password
4349stretching algorithm MUST be cryptographically bound to that keystore. The
4350encryption key MUST NOT be sent off the device (even when wrapped with the user
4351passcode and/or hardware bound key). The upstream Android Open Source project
4352provides a preferred implementation of this feature based on the linux kernel
4353feature dm-crypt.</p>
4354
4355<h2 id="9_10_verified_boot">9.10. Verified Boot</h2>
4356
4357<p>
4358Verified boot is a feature that guarantees the integrity of the device software.
4359If a device implementation supports the feature, it MUST:
Glenn Kasten54e6ac12015-08-12 09:07:12 -0700[diff] [blame]4360</p>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4361<ul>
4362<li>Declare the platform feature flag android.software.verified_boot</li>
4363<li>Perform verification on every boot sequence</li>
4364<li>Start verification from a hardware key that is the root of trust, and go
4365all the way up to the system partition</li>
4366<li>Implement each stage of verification to check the integrity and authenticity
4367of all the bytes in the next stage before executing the code in the next stage</li>
4368<li>Use verification algorithms as strong as current recommendations
4369from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048)</li>
4370</ul>
Unsuk Jung5bc81142015-07-16 22:27:20 -0700[diff] [blame]4371
4372<p>Device implementations SHOULD support verified boot for device integrity.
4373While this requirement is SHOULD for this version of the Android platform,
4374it is <strong>strongly RECOMMENDED</strong> as we expect this to change to MUST
4375in future versions of Android. The upstream Android Open Source Project provides
4376a preferred implementation of this feature based on the linux kernel feature dm-verity.
4377</p>
4378
4379<h1 id="10_software_compatibility_testing">10. Software Compatibility Testing</h1>
4380
4381
4382<p>Device implementations MUST pass all tests described in this section.</p>
4383
4384<p>However, note that no software test package is fully comprehensive. For this
4385reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
4386preferred implementation of Android available from the Android Open Source
4387Project. This will minimize the risk of introducing bugs that create
4388incompatibilities requiring rework and potential device updates.</p>
4389
4390<h2 id="10_1_compatibility_test_suite">10.1. Compatibility Test Suite</h2>
4391
4392
4393<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
4394software on the device. Additionally, device implementers SHOULD use the
4395reference implementation in the Android Open Source tree as much as possible,
4396and MUST ensure compatibility in cases of ambiguity in CTS and for any
4397reimplementations of parts of the reference source code.</p>
4398
4399<p>The CTS is designed to be run on an actual device. Like any software, the CTS
4400may itself contain bugs. The CTS will be versioned independently of this
4401Compatibility Definition, and multiple revisions of the CTS may be released for
4402Android ANDROID_VERSION. Device implementations MUST pass the latest CTS version available
4403at the time the device software is completed.</p>
4404
4405<h2 id="10_2_cts_verifier">10.2. CTS Verifier</h2>
4406
4407
4408<p>Device implementations MUST correctly execute all applicable cases in the CTS
4409Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
4410is intended to be run by a human operator to test functionality that cannot be
4411tested by an automated system, such as correct functioning of a camera and
4412sensors.</p>
4413
4414<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
4415that is optional. Device implementations MUST pass all tests for hardware that
4416they possess; for instance, if a device possesses an accelerometer, it MUST
4417correctly execute the Accelerometer test case in the CTS Verifier. Test cases
4418for features noted as optional by this Compatibility Definition Document MAY be
4419skipped or omitted.</p>
4420
4421<p>Every device and every build MUST correctly run the CTS Verifier, as noted
4422above. However, since many builds are very similar, device implementers are not
4423expected to explicitly run the CTS Verifier on builds that differ only in
4424trivial ways. Specifically, device implementations that differ from an
4425implementation that has passed the CTS Verifier only by the set of included
4426locales, branding, etc. MAY omit the CTS Verifier test.</p>
4427
4428<h1 id="11_updatable_software">11. Updatable Software</h1>
4429
4430
4431<p>Device implementations MUST include a mechanism to replace the entirety of the
4432system software. The mechanism need not perform &ldquo;live&rdquo; upgrades&mdash;that is, a
4433device restart MAY be required.</p>
4434
4435<p>Any method can be used, provided that it can replace the entirety of the
4436software preinstalled on the device. For instance, any of the following
4437approaches will satisfy this requirement:</p>
4438
4439<ul>
4440 <li>&ldquo;Over-the-air (OTA)&rdquo; downloads with offline update via reboot</li>
4441 <li>&ldquo;Tethered&rdquo; updates over USB from a host PC</li>
4442 <li>&ldquo;Offline&rdquo; updates via a reboot and update from a file on removable storage</li>
4443</ul>
4444
4445<p>However, if the device implementation includes support for an unmetered data
4446connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile:</p>
4447
4448<ul>
4449<li>Android Automotive implementations SHOULD support OTA downloads with offline
4450update via reboot.</li>
4451<li>All other device implementations MUST support OTA downloads with offline
4452update via reboot.</li>
4453</ul>
4454
4455<p>The update mechanism used MUST support updates without wiping user data. That
4456is, the update mechanism MUST preserve application private data and application
4457shared data. Note that the upstream Android software includes an update
4458mechanism that satisfies this requirement.</p>
4459
4460<p>For device implementations that are launching with Android ANDROID_VERSION and later, the
4461update mechanism SHOULD support verifying that the system image is binary
4462identical to expected result following an OTA. The block-based OTA
4463implementation in the upstream Android Open Source Project, added since Android
44645.1, satisfies this requirement.</p>
4465
4466<p>If an error is found in a device implementation after it has been released but
4467within its reasonable product lifetime that is determined in consultation with
4468the Android Compatibility Team to affect the compatibility of third-party
4469applications, the device implementer MUST correct the error via a software
4470update available that can be applied per the mechanism just described.</p>
4471
4472<h1 id="12_document_changelog">12. Document Changelog</h1>
4473
4474
4475<p>The following table contains a summary of the changes to the Compatibility
4476Definition in this release. </p>
4477<table>
4478 <tr>
4479 <th>Section</th>
4480 <th>Summary of change</th>
4481 </tr>
4482 <tr>
4483 <td>2. Device Types</td>
4484 <td>Added definition for Android automotive implementation.</td>
4485 </tr>
4486 <tr>
4487 <td>2.1 Device Configurations</td>
4488 <td>Added column for Android automotive implementation.</td>
4489 </tr>
4490 <tr>
4491 <td>3.3.2. 32-bit ARM Native Code Compatibility</td>
4492 <td>New section added.</td>
4493 </tr>
4494 <tr>
4495 <td>3.4.1. WebView Compatibility</td>
4496 <td>Updated webview user agent string requirement to accomodate upstream
4497 implementation change.</td>
4498 </tr>
4499 <tr>
4500 <td>3.4.2. Browser compatibility</td>
4501 <td>Added Android automotive implementations as another case that MAY omit a
4502 browser application.</td>
4503 </tr>
4504 <tr>
4505 <td>3.7. Runtime Compatibility</td>
4506 <td>Updated required runtime heap size for smaller screens and added requirement
4507 for the new dpi bucket (280dpi).</td>
4508 </tr>
4509 <tr>
4510 <td>3.8.3. Notifications</td>
4511 <td>Clarified notification requirement for Android Watch, Television and
4512 Automotive implementations.</td>
4513 </tr>
4514 <tr>
4515 <td>3.8.10. Lock Screen Media Control<</td>
4516 <td>Clarified requirement for Android Watch and Automotive implementations.</td>
4517 </tr>
4518 <tr>
4519 <td>3.8.13. Unicode and font</td>
4520 <td>Relaxed Emoji character input method requirement.</td>
4521 </tr>
4522 <tr>
4523 <td>3.9. Device Administration</td>
4524 <td>Clarified condition when the full range of device administration policies
4525 has to be supported.</td>
4526 </tr>
4527 <tr>
4528 <td>3.10. Accessibility</td>
4529 <td>Added Android automotive requirements.</td>
4530 </tr>
4531 <tr>
4532 <td>3.11. Text-To-Speech</td>
4533 <td>Added Android automotive requirements.</td>
4534 </tr>
4535 <tr>
4536 <td>5.1. Media Codecs</td>
4537 <td>Mandated decoding support for codecs reported by CamcorderProfile.</td>
4538 </tr>
4539 <tr>
4540 <td>5.1.3 Video Codecs</td>
4541 <td>Added Android automotive requirements.</td>
4542 </tr>
4543 <tr>
4544 <td>7.1.1.3. Screen Density</td>
4545 <td>Added a new screen dpi (280dpi).</td>
4546 </tr>
4547 <tr>
4548 <td>7.1.5. Legacy Application Compatibility Mode</td>
4549 <td>Added Android automotive requirements.</td>
4550 </tr>
4551 <tr>
4552 <td>7.2 Input Devices</td>
4553 <td>Added general introduction statement.</td>
4554 </tr>
4555 <tr>
4556 <td>7.2.1. Keyboard</td>
4557 <td>Added Android Automotive requirements.</td>
4558 </tr>
4559 <tr>
4560 <td>7.2.3. Navigation Keys</td>
4561 <td>Added Android Automotive requirements.</td>
4562 </tr>
4563 <tr>
4564 <td>7.3.1. Accelerometer</td>
4565 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4566 </tr>
4567 <tr>
4568 <td>7.3.4. Gyroscope</td>
4569 <td>Relaxed requirement for reporting frequency on Android Watch.</td>
4570 </tr>
4571 <tr>
4572 <td>7.4.3 Bluetooth</td>
4573 <td>Added Android Automotive requirements.</td>
4574 </tr>
4575 <tr>
4576 <td>7.4.4. Near-Field Communications</td>
4577 <td>Clarified condition for when Host Card Emulation is a requirement.</td>
4578 </tr>
4579 <tr>
4580 <td>7.6.1. Minimum Memory and Storage</td>
4581 <td>Updated minimum memory requirements for lower resulution screen devices
4582 and added hard-limit requirement isLowRamDevice().</td>
4583 </tr>
4584 <tr>
4585 <td>7.6.2. Application Shared Storage</td>
4586 <td>Updated requirements when support for host machine access is mandatory.</td>
4587 </tr>
4588 <tr>
4589 <td>7.8.1. Microphone</td>
4590 <td>Added Android Automotive requirements.</td>
4591 </tr>
4592 <tr>
4593 <td>8.2. File I/O Access Performance</td>
4594 <td>Clarified requirements.</td>
4595 </tr>
4596 <tr>
4597 <td>9.8. Privacy</td>
4598 <td>Added privacy requirement for preloaded VPNs.</td>
4599 </tr>
4600 <tr>
4601 <td>9.9. Full-Disk Encryption</td>
4602 <td>Clarified condition when Full-Disk encryption support is mandatory.</td>
4603 </tr>
4604 <tr>
4605 <td>9.10. Verified Boot</td>
4606 <td>Clarified definition of verified boot.</td>
4607 </tr>
4608 <tr>
4609 <td>11. Updatable Software</td>
4610 <td>Clarified the OTA download requirement is allowed but not mandatory for
4611 Android Automotive implementations.</td>
4612 </tr>
4613</table>
4614
4615
4616<h1 id="13_contact_us">13. Contact Us</h1>
4617
4618
4619<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
4620does not cover.</p>
4621
4622<h1 id="14_resources">14. Resources</h1>
4623
4624
4625<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
4626
4627<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
4628
4629<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>
4630
4631<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>
4632
4633<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
4634
4635<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>
4636
4637<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>
4638
4639<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>
4640
4641<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>
4642
4643<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>
4644
4645<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>
4646
4647<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>
4648
4649<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
4650
4651<p>14. HTML5: <a href="http://html.spec.whatwg.org/multipage/">http://html.spec.whatwg.org/multipage/</a></p>
4652
4653<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>
4654
4655<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>
4656
4657<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
4658
4659<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
4660
4661<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
4662
4663<p>20. Dalvik Executable Format and bytecode specification: available in the
4664Android source code, at dalvik/docs</p>
4665
4666<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>
4667
4668<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>
4669
4670<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>
4671
4672<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>
4673
4674<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
4675
4676<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>
4677
4678<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>
4679
4680<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>
4681
4682<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>
4683
4684<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>
4685
4686<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>
4687
4688<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>
4689
4690<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>
4691
4692<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>
4693
4694<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>
4695
4696<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>
4697
4698<p>37. Settings.Secure LOCATION_MODE:</p>
4699
4700<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>
4701
4702<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>
4703
4704<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>
4705
4706<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>
4707
4708<p>41. Android Device Owner App:</p>
4709
4710<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>
4711
4712<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>
4713
4714<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>
4715
4716<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free/">http://code.google.com/p/eyes-free</a></p>
4717
4718<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>
4719
4720<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>
4721
4722<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>
4723
4724<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>
4725
4726<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>
4727
4728<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>
4729
4730<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>
4731
4732<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>
4733
4734<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
4735
4736<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>
4737
4738<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>
4739
4740<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
4741
4742<p>56. Dumpsys: <a href="https://source.android.com/devices/input/diagnostics.html">https://source.android.com/devices/input/diagnostics.html</a> </p>
4743
4744<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
4745
4746<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>
4747
4748<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
4749
4750<p>60. Android Application Development-Related Settings:</p>
4751
4752<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>
4753
4754<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>
4755
4756<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>
4757
4758<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
4759
4760<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>
4761
4762<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>
4763
4764<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
4765
4766<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>
4767
4768<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>
4769
4770<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>
4771
4772<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>
4773
4774<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>
4775
4776<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>
4777
4778<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>
4779
4780<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors</a></p>
4781
4782<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>
4783
4784<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>
4785
4786<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>
4787
4788<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>
4789
4790<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>
4791
4792<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>
4793
4794<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>
4795
4796<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>
4797
4798<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>
4799
4800<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>
4801
4802<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>
4803
4804<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>
4805
4806<p>86. Android NFC Sharing Settings:</p>
4807
4808<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>
4809
4810<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>
4811
4812<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>
4813
4814<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>
4815
4816<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>
4817
4818<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>
4819
4820<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>
4821
4822<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>
4823
4824<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>
4825
4826<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>
4827
4828<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
4829
4830<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>
4831
4832<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>
4833
4834<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>
4835
4836<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>
4837
4838<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>
4839
4840<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>
4841
4842<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>
4843
4844<p>104. External Storage reference: <a href="http://source.android.com/devices/storage">http://source.android.com/devices/storage</a></p>
4845
4846<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>
4847
4848<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
4849
4850<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>
4851
4852<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
4853
4854<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>
4855
4856<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
4857
4858<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>
4859
4860<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>
4861
4862<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>
4863
4864<p>Many of these resources are derived directly or indirectly from the Android
4865SDK, and will be functionally identical to the information in that SDK&rsquo;s
4866documentation. In any cases where this Compatibility Definition or the
4867Compatibility Test Suite disagrees with the SDK documentation, the SDK
4868documentation is considered authoritative. Any technical details provided in
4869the references included above are considered by inclusion to be part of this
4870Compatibility Definition.</p>
4871
4872</div>
4873</body>
4874</html>