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Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]8<h1>Android 5.1 Compatibility Definition</h1>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]9<!--
10<span style="color: red; font-weight: bold;"><h2>Revision 1</h2></span><br/>
11<span style="color: red;">Last updated: July 23, 2013</span>
12-->
13<p><b><font color="red">Revision 1</font></b><br/>
14Last updated: January 12, 2015
15</p>
16<p>Copyright &copy; 2015, Google Inc. All rights reserved.<br/>
17<a href="mailto:compatibility@android.com">compatibility@android.com</a>
18</p>
19
20<h1 id=table_of_contents>Table of Contents</h1>
21
22<table>
23 <tr>
24 <td>
25<p><a href="#heading=h.msc7y995n414">1. Introduction</a></p>
26
27<p><a href="#heading=h.40sdoojaw5k9">2. Device Types</a></p>
28
29<p><a href="#heading=h.562rcc5o7p3c">2.1 Device Configurations</a></p>
30
31<p><a href="#heading=h.yhzgiu12663m">3. Software</a></p>
32
33<p><a href="#heading=h.kr68507hndy4">3.1. Managed API Compatibility</a></p>
34
35<p><a href="#heading=h.klxc9p5alm1k">3.2. Soft API Compatibility</a></p>
36
37<p><a href="#heading=h.db11p7gvg81n">3.2.1. Permissions</a></p>
38
39<p><a href="#heading=h.3710ebc7nsew">3.2.2. Build Parameters</a></p>
40
41<p><a href="#heading=h.gthv9fjcs0pe">3.2.3. Intent Compatibility</a></p>
42
43<p><a href="#heading=h.qiy4ddbiirgy">3.2.3.1. Core Application Intents</a></p>
44
45<p><a href="#heading=h.bpmvwqbxsymp">3.2.3.2. Intent Overrides</a></p>
46
47<p><a href="#heading=h.r3yyvgtvim43">3.2.3.3. Intent Namespaces</a></p>
48
49<p><a href="#heading=h.r8urpa426zy">3.2.3.4. Broadcast Intents</a></p>
50
51<p><a href="#heading=h.oek6k3rdi0v8">3.2.3.5. Default App Settings</a></p>
52
53<p><a href="#heading=h.3dpths90svxf">3.3. Native API Compatibility</a></p>
54
55<p><a href="#heading=h.jcm6fp8o7lhj">3.3.1 Application Binary Interfaces</a></p>
56
57<p><a href="#heading=h.svlldf3npn1t">3.4. Web Compatibility</a></p>
58
59<p><a href="#heading=h.swqsalizdkk8">3.4.1. WebView Compatibility</a></p>
60
61<p><a href="#heading=h.minm6jqu934x">3.4.2. Browser Compatibility</a></p>
62
63<p><a href="#heading=h.xq343byyb0fz">3.5. API Behavioral Compatibility</a></p>
64
65<p><a href="#heading=h.blmhfmxlmvir">3.6. API Namespaces</a></p>
66
67<p><a href="#heading=h.5159yfnui03c">3.7. Runtime Compatibility</a></p>
68
69<p><a href="#heading=h.6jv9libgzj5i">3.8. User Interface Compatibility</a></p>
70
71<p><a href="#heading=h.uihb1eijkvo">3.8.1. Launcher (Home Screen)</a></p>
72
73<p><a href="#heading=h.v9h5ffzht332">3.8.2. Widgets</a></p>
74
75<p><a href="#heading=h.i9vjtu1lr6go">3.8.3. Notifications</a></p>
76
77<p><a href="#heading=h.6hexhtx5tmrs">3.8.4. Search</a></p>
78
79<p><a href="#heading=h.xc1emmi207w5">3.8.5. Toasts</a></p>
80
81<p><a href="#heading=h.qip8398skywq">3.8.6. Themes</a></p>
82
83<p><a href="#heading=h.c5ay2hae9td">3.8.7. Live Wallpapers</a></p>
84
85<p><a href="#heading=h.zc10jlx04bz">3.8.8. Activity Switching</a></p>
86
87<p><a href="#heading=h.z2dmdulh39vh">3.8.9. Input Management</a></p>
88
89<p><a href="#heading=h.y1dfuxk4g759">3.8.10. Lock Screen Media Control</a></p>
90
91<p><a href="#heading=h.w9tpfodgdigq">3.8.11. Dreams</a></p>
92
93<p><a href="#heading=h.ifi3tjbpjckl">3.8.12. Location</a></p>
94
95<p><a href="#heading=h.ugmg9aj091f8">3.8.13. Unicode and Font</a></p>
96
97<p><a href="#heading=h.yyjxs5mhy231">3.9. Device Administration</a></p>
98
99<p><a href="#heading=h.ynv25r97q6m">3.10. Accessibility</a></p>
100
101<p><a href="#heading=h.d6m0oago1d3y">3.11. Text-to-Speech</a></p>
102
103<p><a href="#heading=h.zdns59cgtxwy">3.12. TV Input Framework</a></p>
104
105<p><a href="#heading=h.z51ce4vpkix">4. Application Packaging Compatibility</a></p>
106
107<p><a href="#heading=h.ddcqv1ggh4y7">5. Multimedia Compatibility</a></p>
108
109<p><a href="#heading=h.qj4xbxk4bysl">5.1. Media Codecs</a></p>
110
111<p><a href="#heading=h.iad8gjulqe75">5.1.1. Audio Codecs</a></p>
112
113<p><a href="#heading=h.rv9qy784zhuc">5.1.2. Image Codecs</a></p>
114
115<p><a href="#heading=h.gxu0pnbldfle">5.1.3. Video Codecs</a></p>
116
117<p><a href="#heading=h.be1ledetmole">5.2. Video Encoding</a></p>
118
119<p><a href="#heading=h.7971wdynbtij">5.3. Video Decoding</a></p>
120
121<p><a href="#heading=h.vtmgyrsev5dt">5.4. Audio Recording</a></p>
122
123<p><a href="#heading=h.ng7fac8ci8vj">5.4.1. Raw Audio Capture</a></p>
124
125<p><a href="#heading=h.sro7nvcaeuc1">5.4.2. Capture for Voice Recognition</a></p>
126
127<p><a href="#heading=h.n5ikz5dupfno">5.4.3. Capture for Rerouting of Playback</a></p>
128
129<p><a href="#heading=h.1xocvxnwynnm">5.5. Audio Playback</a></p>
130
131<p><a href="#heading=h.6zy7486s5cfa">5.5.1. Raw Audio Playback</a></p>
132
133<p><a href="#heading=h.ai1naitm7qfy">5.5.2. Audio Effects</a></p>
134
135<p><a href="#heading=h.fngymkz0321y">5.5.3. Audio Output Volume</a></p>
136
137<p><a href="#heading=h.qpj70us2l5pn">5.6. Audio Latency</a></p>
138
139<p><a href="#heading=h.1p55xhbym9l4">5.7. Network Protocols</a></p>
140
141<p><a href="#heading=h.mpxr2yu72m6t">5.8. Secure Media</a></p>
142
143<p><a href="#heading=h.9v14hzhfhm3p">6. Developer Tools and Options Compatibility</a></p>
144
145<p><a href="#heading=h.9cfw1b5q4g96">6.1. Developer Tools</a></p>
146
147<p><a href="#heading=h.yipuqt964xra">6.2. Developer Options</a></p>
148
149<p><a href="#heading=h.5h5uvpadidzr">7. Hardware Compatibility</a></p>
150
151<p><a href="#heading=h.22h5j37xan6e">7.1. Display and Graphics</a></p>
152
153<p><a href="#heading=h.6fey5v3qb5m3">7.1.1. Screen Configuration</a></p>
154
155<p><a href="#heading=h.mrv5xyps1ba8">7.1.1.1. Screen Size</a></p>
156
157<p><a href="#heading=h.h4amzk7515h2">7.1.1.2. Screen Aspect Ratio</a></p>
158
159<p><a href="#heading=h.2d6r63hcnjt0">7.1.1.3. Screen Density</a></p>
160
161<p><a href="#heading=h.p3dcj1v9ofv0">7.1.2. Display Metrics</a></p>
162</td>
163 </tr>
164</table>
165
166<table>
167 <tr>
168 <td>
169<p><a href="#heading=h.try1r2p8m3vf">7.1.3. Screen Orientation</a></p>
170
171<p><a href="#heading=h.r5sa5dwl0cjh">7.1.4. 2D and 3D Graphics Acceleration</a></p>
172
173<p><a href="#heading=h.r1yeedum5wsi">7.1.5. Legacy Application Compatibility Mode</a></p>
174
175<p><a href="#heading=h.dvbqyf6vof9p">7.1.6. Screen Technology</a></p>
176
177<p><a href="#heading=h.yeaulmskczp3">7.1.7. External Displays</a></p>
178
179<p><a href="#heading=h.1rhjcel5zbe5">7.2. Input Devices</a></p>
180
181<p><a href="#heading=h.egbk02citmz">7.2.1. Keyboard</a></p>
182
183<p><a href="#heading=h.h86aqgcxrqbz">7.2.2. Non-touch Navigation</a></p>
184
185<p><a href="#heading=h.dzfhwcjzm5z6">7.2.3. Navigation Keys</a></p>
186
187<p><a href="#heading=h.p7pmjzzatkph">7.2.4. Touchscreen Input</a></p>
188
189<p><a href="#heading=h.7tz929qk2hjr">7.2.5. Fake Touch Input</a></p>
190
191<p><a href="#heading=h.sdgxpot7e9ff">7.2.6. Game Controller Support</a></p>
192
193<p><a href="#heading=h.e96izopb7n42">7.2.6.1. Button Mappings</a></p>
194
195<p><a href="#heading=h.eija3q5owqll">7.2.7. Remote Control</a></p>
196
197<p><a href="#heading=h.j40lqogjtait">7.3. Sensors</a></p>
198
199<p><a href="#heading=h.3u857dtnrtuj">7.3.1. Accelerometer</a></p>
200
201<p><a href="#heading=h.sf5gr3iz7tz4">7.3.2. Magnetometer</a></p>
202
203<p><a href="#heading=h.2x1nre62p60d">7.3.3. GPS</a></p>
204
205<p><a href="#heading=h.kczbjun4pvap">7.3.4. Gyroscope</a></p>
206
207<p><a href="#heading=h.vmgl07rl8eir">7.3.5. Barometer</a></p>
208
209<p><a href="#heading=h.7gtmh7pqnekm">7.3.6. Thermometer</a></p>
210
211<p><a href="#heading=h.nbgggpsrc5wj">7.3.7. Photometer</a></p>
212
213<p><a href="#heading=h.gus8hybydyk8">7.3.8. Proximity Sensor</a></p>
214
215<p><a href="#heading=h.7y7dtt5ikji6">7.4. Data Connectivity</a></p>
216
217<p><a href="#heading=h.u12n5f7z5iiq">7.4.1. Telephony</a></p>
218
219<p><a href="#heading=h.39g0jrqcl40">7.4.2. IEEE 802.11 (Wi-Fi)</a></p>
220
221<p><a href="#heading=h.82i6ovyqynfx">7.4.2.1. Wi-Fi Direct</a></p>
222
223<p><a href="#heading=h.aia2dpbgueab">7.4.2.2. Wi-Fi Tunneled Direct Link Setup</a></p>
224
225<p><a href="#heading=h.420i0exy2mxj">7.4.3. Bluetooth</a></p>
226
227<p><a href="#heading=h.twzy3bitgp2k">7.4.4. Near-Field Communications</a></p>
228
229<p><a href="#heading=h.sg0l1jarhok9">7.4.5. Minimum Network Capability</a></p>
230
231<p><a href="#heading=h.7agkwed6used">7.4.6. Sync Settings</a></p>
232
233<p><a href="#heading=h.ups9ebpvb6ja">7.5. Cameras</a></p>
234
235<p><a href="#heading=h.v6dmzvarwqkm">7.5.1. Rear-Facing Camera</a></p>
236
237<p><a href="#heading=h.xze6dyxaadh9">7.5.2. Front-Facing Camera</a></p>
238
239<p><a href="#heading=h.q85mgg9m8zhf">7.5.3. External Camera</a></p>
240
241<p><a href="#heading=h.s349dbv4ffl4">7.5.4. Camera API Behavior</a></p>
242
243<p><a href="#heading=h.zguadou53wls">7.5.5. Camera Orientation</a></p>
244
245<p><a href="#heading=h.bodawgb0ngf8">7.6. Memory and Storage</a></p>
246
247<p><a href="#heading=h.q4aoj3xvrlxe">7.6.1. Minimum Memory and Storage</a></p>
248
249<p><a href="#heading=h.8qr43vll8ow">7.6.2. Application Shared Storage</a></p>
250
251<p><a href="#heading=h.rp4zc78xvn6s">7.7. USB</a></p>
252
253<p><a href="#heading=h.fzr0lrcrrfak">7.8. Audio</a></p>
254
255<p><a href="#heading=h.74o7ndqnyrjr">7.8.1. Microphone</a></p>
256
257<p><a href="#heading=h.ro0d402dzkaq">7.8.2. Audio Output</a></p>
258
259<p><a href="#heading=h.luy58niin3j">7.8.2.1. Analog Audio Ports</a></p>
260
261<p><a href="#heading=h.v33sc890yqtg">8. Performance Compatibility</a></p>
262
263<p><a href="#heading=h.jyh6oga0ubgs">8.1. User Experience Consistency</a></p>
264
265<p><a href="#heading=h.9vv5a25p8zcz">8.2. Memory Performance</a></p>
266
267<p><a href="#heading=h.a32osmf1tmwt">9. Security Model Compatibility</a></p>
268
269<p><a href="#heading=h.rj8bxiqpff6s">9.1. Permissions</a></p>
270
271<p><a href="#heading=h.p4gtpuihccdf">9.2. UID and Process Isolation</a></p>
272
273<p><a href="#heading=h.en5p20nyss66">9.3. Filesystem Permissions</a></p>
274
275<p><a href="#heading=h.p5sjwl72r3oz">9.4. Alternate Execution Environments</a></p>
276
277<p><a href="#heading=h.xspotnaue6fc">9.5. Multi-User Support</a></p>
278
279<p><a href="#heading=h.7b5lq2p9nv4j">9.6. Premium SMS Warning</a></p>
280
281<p><a href="#heading=h.io2qcx4xe6hh">9.7. Kernel Security Features</a></p>
282
283<p><a href="#heading=h.u9w027jkf7bb">9.8. Privacy</a></p>
284
285<p><a href="#heading=h.qq3tcq94r919">9.9. Full-Disk Encryption</a></p>
286
287<p><a href="#heading=h.ngllntwu29p6">9.10. Verified Boot</a></p>
288
289<p><a href="#heading=h.rafv96b0uwer">10. Software Compatibility Testing</a></p>
290
291<p><a href="#heading=h.7iuzt59bizon">10.1. Compatibility Test Suite</a></p>
292
293<p><a href="#heading=h.opluz3h21s0b">10.2. CTS Verifier</a></p>
294
295<p><a href="#heading=h.141487psajcw">11. Updatable Software</a></p>
296
297<p><a href="#heading=h.4et8ifl401m5">12. Document Changelog</a></p>
298
299<p><a href="#heading=h.codus8wcjysp">13. Contact Us</a></p>
300
301<p><a href="#heading=h.jhgs5yq2lqtj">14. Resources</a></p>
302</td>
303 </tr>
304</table>
305
306<h1 id=1_introduction>1. Introduction</h1>
307
308
309<p>This document enumerates the requirements that must be met in order for devices
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]310to be compatible with Android 5.1.</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]311
312<p>The use of "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
313"SHOULD NOT", "RECOMMENDED", "MAY" and "OPTIONAL" is per the IETF standard
314defined in RFC2119 [<a href="http://www.ietf.org/rfc/rfc2119.txt">Resources, 1</a>].</p>
315
316<p>As used in this document, a "device implementer" or "implementer" is a person
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]317or organization developing a hardware/software solution running Android 5.1. A
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]318"device implementation" or "implementation" is the hardware/software solution
319so developed.</p>
320
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]321<p>To be considered compatible with Android 5.1, device implementations MUST meet
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]322the requirements presented in this Compatibility Definition, including any
323documents incorporated via reference.</p>
324
325<p>Where this definition or the software tests described in <a href="#heading=h.rafv96b0uwer">section 10</a> is silent, ambiguous, or incomplete, it is the responsibility of the device
326implementer to ensure compatibility with existing implementations.</p>
327
328<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
329implementers are strongly encouraged to base their implementations to the
330greatest extent possible on the "upstream" source code available from the
331Android Open Source Project. While some components can hypothetically be
332replaced with alternate implementations this practice is strongly discouraged,
333as passing the software tests will become substantially more difficult. It is
334the implementer's responsibility to ensure full behavioral compatibility with
335the standard Android implementation, including and beyond the Compatibility
336Test Suite. Finally, note that certain component substitutions and
337modifications are explicitly forbidden by this document.</p>
338
339<p>Many of the resources listed in <a href="#heading=h.jhgs5yq2lqtj">section 14</a> are derived directly or indirectly from the Android SDK, and will be
340functionally identical to the information in that SDK's documentation. For any
341case where this Compatibility Definition or the Compatibility Test Suite
342disagrees with the SDK documentation, the SDK documentation is considered
343authoritative. Any technical details provided in the references included in <a href="#heading=h.jhgs5yq2lqtj">section 14</a> are considered by inclusion to be part of this Compatibility Definition. </p>
344
345<h1 id=2_device_types>2. Device Types</h1>
346
347
348<p>While the Android Open Source Project has been used in the implementation of a
349variety of device types and form factors, many aspects of the architecture and
350compatibility requirements were optimized for handheld devices. Starting from
351Android 5.0, the Android Open Source Project aims to embrace a wider variety of
352device types as described in this section.</p>
353
354<p><strong>Android Handheld device</strong> refers to an Android device implementation that is typically used by holding
355it in the hand, such as mp3 players, phones, and tablets. Android Handheld
356device implementations:</p>
357
358<ul>
359 <li> MUST have a touchscreen embedded in the device
360 <li> MUST have a power source that provides mobility, such as a battery
361</ul>
362
363<p><strong>Android Television device</strong> refers to an Android device implementation that is an entertainment interface
364for consuming digital media, movies, games, apps, and/or live TV for users
365sitting about ten feet away (a “lean back” or “10-foot user interface”).
366Android Television devices:</p>
367
368<ul>
369 <li> MUST have an embedded screen OR include a video output port, such as VGA, HDMI,
370or a wireless port for display
371 <li> MUST declare the features android.software.leanback and
372android.hardware.type.television [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html#FEATURE_LEANBACK">Resources, 3</a>]
373</ul>
374
375<p><strong>Android Watch device</strong> refers to an Android device implementation intended to be worn on the body,
376perhaps on the wrist, and:</p>
377
378<ul>
379 <li> MUST have a screen with the physical diagonal length in the range from 1.1 to
3802.5 inches
381 <li> MUST declare the feature android.hardware.type.watch
382 <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>]
383</ul>
384
385<p>All Android device implementations that do not fit into any of the above device
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]386types still MUST meet all requirements in this document to be Android 5.1
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]387compatible, unless the requirement is explicitly described to be only
388applicable to a specific Android device type. </p>
389
390<h2 id=2_1_device_configurations>2.1 Device Configurations</h2>
391
392
393<p>This is a summary of major differences in hardware configuration by device
394type. (Empty cells denote a “MAY”). Not all configurations are covered in this
395table; see relevant hardware sections for more detail.</p>
396<table>
397 <tr>
398 <td class="tab0">
399<p><strong>Category</strong></p>
400</td>
401 <td class="tab0">
402<p><strong>Feature </strong></p>
403</td>
404 <td class="tab0">
405<p><strong>Section</strong></p>
406</td>
407 <td class="tab0">
408<p><strong>Handheld</strong></p>
409</td>
410 <td class="tab0">
411<p><strong>Television</strong></p>
412</td>
413 <td class="tab0">
414<p><strong>Watch</strong></p>
415</td>
416 <td class="tab0">
417<p><strong>Other</strong></p>
418</td>
419 </tr>
420 <tr>
421 <td>
422<p>Input</p>
423</td>
424 <td>
425<p>D-pad</p>
426</td>
427 <td>
428<p><a href="#heading=h.h86aqgcxrqbz">7.2.2. Non-touch Navigation</a></p>
429</td>
430 <td></td>
431 <td>
432<p>MUST</p>
433</td>
434 <td></td>
435 <td></td>
436 </tr>
437 <tr>
438 <td></td>
439 <td>
440<p>Touchscreen </p>
441</td>
442 <td>
443<p> <a href="#heading=h.p7pmjzzatkph">7.2.4. Touchscreen input</a></p>
444</td>
445 <td>
446<p>MUST</p>
447</td>
448 <td></td>
449 <td>
450<p>MUST</p>
451</td>
452 <td>
453<p>SHOULD</p>
454</td>
455 </tr>
456 <tr>
457 <td></td>
458 <td>
459<p>Microphone </p>
460</td>
461 <td>
462<p><a href="#heading=h.74o7ndqnyrjr">7.8.1. Microphone</a></p>
463</td>
464 <td>
465<p>MUST</p>
466</td>
467 <td>
468<p>SHOULD </p>
469</td>
470 <td>
471<p>MUST</p>
472</td>
473 <td>
474<p>SHOULD</p>
475</td>
476 </tr>
477 <tr>
478 <td>
479<p>Sensors</p>
480</td>
481 <td>
482<p>Accelerometer </p>
483</td>
484 <td>
485<p><a href="#heading=h.3u857dtnrtuj">7.3.1 Accelerometer</a></p>
486</td>
487 <td>
488<p>SHOULD</p>
489</td>
490 <td></td>
491 <td>
492<p>SHOULD</p>
493</td>
494 <td>
495<p>SHOULD</p>
496</td>
497 </tr>
498 <tr>
499 <td></td>
500 <td>
501<p>GPS </p>
502</td>
503 <td>
504<p><a href="#heading=h.2x1nre62p60d">7.3.3. GPS</a></p>
505</td>
506 <td>
507<p>SHOULD</p>
508</td>
509 <td></td>
510 <td></td>
511 <td></td>
512 </tr>
513 <tr>
514 <td>
515<p>Connectivity</p>
516</td>
517 <td>
518<p>Wi-Fi </p>
519</td>
520 <td>
521<p><a href="#heading=h.39g0jrqcl40">7.4.2. IEEE 802.11</a></p>
522</td>
523 <td>
524<p>SHOULD</p>
525</td>
526 <td>
527<p> MUST</p>
528</td>
529 <td></td>
530 <td>
531<p>SHOULD</p>
532</td>
533 </tr>
534 <tr>
535 <td></td>
536 <td>
537<p>Wi-Fi Direct </p>
538</td>
539 <td>
540<p><a href="#heading=h.82i6ovyqynfx">7.4.2.1. Wi-Fi Direct</a></p>
541</td>
542 <td>
543<p>SHOULD</p>
544</td>
545 <td>
546<p>SHOULD</p>
547</td>
548 <td></td>
549 <td>
550<p>SHOULD</p>
551</td>
552 </tr>
553 <tr>
554 <td></td>
555 <td>
556<p>Bluetooth </p>
557</td>
558 <td>
559<p><a href="#heading=h.420i0exy2mxj">7.4.3. Bluetooth</a></p>
560</td>
561 <td>
562<p>SHOULD</p>
563</td>
564 <td>
565<p>MUST</p>
566</td>
567 <td>
568<p>MUST</p>
569</td>
570 <td>
571<p>SHOULD</p>
572</td>
573 </tr>
574 <tr>
575 <td></td>
576 <td>
577<p>Bluetooth Low Energy </p>
578</td>
579 <td>
580<p><a href="#heading=h.420i0exy2mxj">7.4.3. Bluetooth</a></p>
581</td>
582 <td>
583<p>SHOULD</p>
584</td>
585 <td>
586<p>MUST</p>
587</td>
588 <td>
589<p>SHOULD</p>
590</td>
591 <td>
592<p>SHOULD</p>
593</td>
594 </tr>
595 <tr>
596 <td></td>
597 <td>
598<p>USB peripheral/ host mode </p>
599</td>
600 <td>
601<p><a href="#heading=h.rp4zc78xvn6s">7.7. USB</a></p>
602</td>
603 <td>
604<p>SHOULD</p>
605</td>
606 <td>
607<p> </p>
608</td>
609 <td></td>
610 <td>
611<p>SHOULD</p>
612</td>
613 </tr>
614 <tr>
615 <td>
616<p>Output</p>
617</td>
618 <td>
619<p>Speaker and/or Audio output ports </p>
620</td>
621 <td>
622<p><a href="#heading=h.ro0d402dzkaq">7.8.2. Audio Output</a></p>
623</td>
624 <td>
625<p>MUST</p>
626</td>
627 <td>
628<p>MUST</p>
629</td>
630 <td></td>
631 <td>
632<p>MUST</p>
633</td>
634 </tr>
635</table>
636
637
638<h1 id=3_software>3. Software</h1>
639
640
641<h2 id=3_1_managed_api_compatibility>3.1. Managed API Compatibility</h2>
642
643
644<p>The managed Dalvik bytecode execution environment is the primary vehicle for
645Android applications. The Android application programming interface (API) is
646the set of Android platform interfaces exposed to applications running in the
647managed runtime environment. Device implementations MUST provide complete
648implementations, including all documented behaviors, of any documented API
649exposed by the Android SDK [<a href="http://developer.android.com/reference/packages.html">Resources, 5</a>] or any API decorated with the "@SystemApi" marker in the upstream Android
650source code. </p>
651
652<p>Device implementations MUST NOT omit any managed APIs, alter API interfaces or
653signatures, deviate from the documented behavior, or include no-ops, except
654where specifically allowed by this Compatibility Definition.</p>
655
656<p>This Compatibility Definition permits some types of hardware for which Android
657includes APIs to be omitted by device implementations. In such cases, the APIs
658MUST still be present and behave in a reasonable way. See <a href="#heading=h.5h5uvpadidzr">section 7</a> for specific requirements for this scenario.</p>
659
660<h2 id=3_2_soft_api_compatibility>3.2. Soft API Compatibility</h2>
661
662
663<p>In addition to the managed APIs from <a href="#heading=h.kr68507hndy4">section 3.1</a>, Android also includes a significant runtime-only "soft" API, in the form of
664such things as intents, permissions, and similar aspects of Android
665applications that cannot be enforced at application compile time.</p>
666
667<h3 id=3_2_1_permissions>3.2.1. Permissions</h3>
668
669
670<p>Device implementers MUST support and enforce all permission constants as
671documented by the Permission reference page [<a href="http://developer.android.com/reference/android/Manifest.permission.html">Resources, 6]</a>. Note that <a href="#heading=h.a32osmf1tmwt">section 9</a> lists additional requirements related to the Android security model.</p>
672
673<h3 id=3_2_2_build_parameters>3.2.2. Build Parameters</h3>
674
675
676<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,
677meaningful values across device implementations, the table below includes
678additional restrictions on the formats of these values to which device
679implementations MUST conform.</p>
680<table>
681 <tr>
682 <td class="tab0">
683<p><strong>Parameter</strong></p>
684</td>
685 <td class="tab0">
686<p><strong>Details</strong></p>
687</td>
688 </tr>
689 <tr>
690 <td>
691<p>VERSION.RELEASE</p>
692</td>
693 <td>
694<p>The version of the currently-executing Android system, in human-readable
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]695format. This field MUST have one of the string values defined in [<a href="http://source.android.com/compatibility/5.1/versions.html">Resources, 8]</a>.</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]696</td>
697 </tr>
698 <tr>
699 <td>
700<p>VERSION.SDK</p>
701</td>
702 <td>
703<p>The version of the currently-executing Android system, in a format accessible
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]704to third-party application code. For Android 5.1, this field MUST have the
705integer value 22.</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]706</td>
707 </tr>
708 <tr>
709 <td>
710<p>VERSION.SDK_INT</p>
711</td>
712 <td>
713<p>The version of the currently-executing Android system, in a format accessible
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]714to third-party application code. For Android 5.1, this field MUST have the
715integer value 22.</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]716</td>
717 </tr>
718 <tr>
719 <td>
720<p>VERSION.INCREMENTAL</p>
721</td>
722 <td>
723<p>A value chosen by the device implementer designating the specific build of the
724currently-executing Android system, in human-readable format. This value MUST
725NOT be reused for different builds made available to end users. A typical use
726of this field is to indicate which build number or source-control change
727identifier was used to generate the build. There are no requirements on the
728specific format of this field, except that it MUST NOT be null or the empty
729string ("").</p>
730</td>
731 </tr>
732 <tr>
733 <td>
734<p>BOARD</p>
735</td>
736 <td>
737<p>A value chosen by the device implementer identifying the specific internal
738hardware used by the device, in human-readable format. A possible use of this
739field is to indicate the specific revision of the board powering the device.
740The value of this field MUST be encodable as 7-bit ASCII and match the regular
741expression "^[a-zA-Z0-9_-]+$".</p>
742</td>
743 </tr>
744 <tr>
745 <td>
746<p>BRAND</p>
747</td>
748 <td>
749<p>A value reflecting the brand name associated with the device as known to the
750end users. MUST be in human-readable format and SHOULD represent the
751manufacturer of the device or the company brand under which the device is
752marketed. The value of this field MUST be encodable as 7-bit ASCII and match
753the regular expression "^[a-zA-Z0-9_-]+$".</p>
754</td>
755 </tr>
756 <tr>
757 <td class="tab1">
758<p>SUPPORTED_ABIS</p>
759</td>
760 <td>
761<p>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#heading=h.3dpths90svxf">section 3.3. Native API Compatibility</a>.</p>
762</td>
763 </tr>
764 <tr>
765 <td class="tab1">
766<p>SUPPORTED_32_BIT_ABIS</p>
767</td>
768 <td>
769<p>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#heading=h.3dpths90svxf">section 3.3. Native API Compatibility</a>.</p>
770</td>
771 </tr>
772 <tr>
773 <td class="tab1">
774<p>SUPPORTED_64_BIT_ABIS</p>
775</td>
776 <td>
777<p>The name of the second instruction set (CPU type + ABI convention) of native
778code. See <a href="#heading=h.3dpths90svxf">section 3.3. Native API Compatibility</a>.</p>
779</td>
780 </tr>
781 <tr>
782 <td>
783<p>CPU_ABI</p>
784</td>
785 <td>
786<p>The name of the instruction set (CPU type + ABI convention) of native code. See <a href="#heading=h.3dpths90svxf">section 3.3. Native API Compatibility</a>.</p>
787</td>
788 </tr>
789 <tr>
790 <td>
791<p>CPU_ABI2</p>
792</td>
793 <td>
794<p>The name of the second instruction set (CPU type + ABI convention) of native
795code. See <a href="#heading=h.3dpths90svxf">section 3.3. Native API Compatibility</a>.</p>
796</td>
797 </tr>
798 <tr>
799 <td>
800<p>DEVICE</p>
801</td>
802 <td>
803<p>A value chosen by the device implementer containing the development name or
804code name identifying the configuration of the hardware features and industrial
805design of the device. The value of this field MUST be encodable as 7-bit ASCII
806and match the regular expression "^[a-zA-Z0-9_-]+$".</p>
807</td>
808 </tr>
809 <tr>
810 <td>
811<p>FINGERPRINT</p>
812</td>
813 <td>
814<p>A string that uniquely identifies this build. It SHOULD be reasonably
815human-readable. It MUST follow this template:</p>
816
817<p>$(BRAND)/$(PRODUCT)/$(DEVICE):$(VERSION.RELEASE)/$(ID)/$(VERSION.INCREMENTAL):$(TYPE)/$(TAGS)</p>
818
819<p>For example:</p>
820
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]821<p>acme/myproduct/mydevice:5.1/LMYXX/3359:userdebug/test-keys</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]822
823<p>The fingerprint MUST NOT include whitespace characters. If other fields
824included in the template above have whitespace characters, they MUST be
825replaced in the build fingerprint with another character, such as the
826underscore ("_") character. The value of this field MUST be encodable as 7-bit
827ASCII.</p>
828</td>
829 </tr>
830 <tr>
831 <td>
832<p>HARDWARE</p>
833</td>
834 <td>
835<p>The name of the hardware (from the kernel command line or /proc). It SHOULD be
836reasonably human-readable. The value of this field MUST be encodable as 7-bit
837ASCII and match the regular expression "^[a-zA-Z0-9_-]+$". </p>
838</td>
839 </tr>
840 <tr>
841 <td>
842<p>HOST</p>
843</td>
844 <td>
845<p>A string that uniquely identifies the host the build was built on, in
846human-readable format. There are no requirements on the specific format of this
847field, except that it MUST NOT be null or the empty string ("").</p>
848</td>
849 </tr>
850 <tr>
851 <td>
852<p>ID</p>
853</td>
854 <td>
855<p>An identifier chosen by the device implementer to refer to a specific release,
856in human-readable format. This field can be the same as
857android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently
858meaningful for end users to distinguish between software builds. The value of
859this field MUST be encodable as 7-bit ASCII and match the regular expression
860"^[a-zA-Z0-9._-]+$".</p>
861</td>
862 </tr>
863 <tr>
864 <td>
865<p>MANUFACTURER</p>
866</td>
867 <td>
868<p>The trade name of the Original Equipment Manufacturer (OEM) of the product.
869There are no requirements on the specific format of this field, except that it
870MUST NOT be null or the empty string ("").</p>
871</td>
872 </tr>
873 <tr>
874 <td>
875<p>MODEL</p>
876</td>
877 <td>
878<p>A value chosen by the device implementer containing the name of the device as
879known to the end user. This SHOULD be the same name under which the device is
880marketed and sold to end users. There are no requirements on the specific
881format of this field, except that it MUST NOT be null or the empty string ("").</p>
882</td>
883 </tr>
884 <tr>
885 <td>
886<p>PRODUCT</p>
887</td>
888 <td>
889<p>A value chosen by the device implementer containing the development name or
890code name of the specific product (SKU) that MUST be unique within the same
891brand. MUST be human-readable, but is not necessarily intended for view by end
892users. The value of this field MUST be encodable as 7-bit ASCII and match the
893regular expression "^[a-zA-Z0-9_-]+$".</p>
894</td>
895 </tr>
896 <tr>
897 <td>
898<p>SERIAL</p>
899</td>
900 <td>
901<p>A hardware serial number, which MUST be available. The value of this field MUST
902be encodable as 7-bit ASCII and match the regular expression
903"^([a-zA-Z0-9]{6,20})$".</p>
904</td>
905 </tr>
906 <tr>
907 <td>
908<p>TAGS</p>
909</td>
910 <td>
911<p>A comma-separated list of tags chosen by the device implementer that further
912distinguishes the build. This field MUST have one of the values corresponding
913to the three typical Android platform signing configurations: release-keys,
914dev-keys, test-keys. </p>
915</td>
916 </tr>
917 <tr>
918 <td>
919<p>TIME</p>
920</td>
921 <td>
922<p>A value representing the timestamp of when the build occurred.</p>
923</td>
924 </tr>
925 <tr>
926 <td>
927<p>TYPE</p>
928</td>
929 <td>
930<p>A value chosen by the device implementer specifying the runtime configuration
931of the build. This field MUST have one of the values corresponding to the three
932typical Android runtime configurations: user, userdebug, or eng.</p>
933</td>
934 </tr>
935 <tr>
936 <td>
937<p>USER</p>
938</td>
939 <td>
940<p>A name or user ID of the user (or automated user) that generated the build.
941There are no requirements on the specific format of this field, except that it
942MUST NOT be null or the empty string ("").</p>
943</td>
944 </tr>
945</table>
946
947
948<h3 id=3_2_3_intent_compatibility>3.2.3. Intent Compatibility</h3>
949
950
951<p>Device implementations MUST honor Android's loose-coupling intent system, as
952described in the sections below. By "honored", it is meant that the device
953implementer MUST provide an Android Activity or Service that specifies a
954matching intent filter that binds to and implements correct behavior for each
955specified intent pattern.</p>
956
957<h4 id=3_2_3_1_core_application_intents>3.2.3.1. Core Application Intents</h4>
958
959
960<p>Android intents allow application components to request functionality from
961other Android components. The Android upstream project includes a list of
962applications considered core Android applications, which implements several
963intent patterns to perform common actions. The core Android applications are:</p>
964
965<ul>
966 <li> Desk Clock
967 <li> Browser
968 <li> Calendar
969 <li> Contacts
970 <li> Gallery
971 <li> GlobalSearch
972 <li> Launcher
973 <li> Music
974 <li> Settings
975</ul>
976
977<p>Device implementations SHOULD include the core Android applications as
978appropriate but MUST include a component implementing the same intent patterns
979defined by all the “public” Activity or Service components of these core
980Android applications. Note that Activity or Service components are considered
981"public" when the attribute android:exported is absent or has the value true.</p>
982
983<h4 id=3_2_3_2_intent_overrides>3.2.3.2. Intent Overrides</h4>
984
985
986<p>As Android is an extensible platform, device implementations MUST allow each
987intent pattern referenced in <a href="#heading=h.qiy4ddbiirgy">section 3.2.3.1</a> to be overridden by third-party applications. The upstream Android open source
988implementation allows this by default; device implementers MUST NOT attach
989special privileges to system applications' use of these intent patterns, or
990prevent third-party applications from binding to and assuming control of these
991patterns. This prohibition specifically includes but is not limited to
992disabling the "Chooser" user interface that allows the user to select between
993multiple applications that all handle the same intent pattern.</p>
994
995<p>However, device implementations MAY provide default activities for specific URI
996patterns (eg. http://play.google.com) if the default activity provides a more
997specific filter for the data URI. For example, an intent filter specifying the
998data URI "http://www.android.com" is more specific than the browser filter for
999"http://". Device implementations MUST provide a user interface for users to
1000modify the default activity for intents.</p>
1001
1002<h4 id=3_2_3_3_intent_namespaces>3.2.3.3. Intent Namespaces</h4>
1003
1004
1005<p>Device implementations MUST NOT include any Android component that honors any
1006new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key
1007string in the android.* or com.android.* namespace. Device implementers MUST
1008NOT include any Android components that honor any new intent or broadcast
1009intent patterns using an ACTION, CATEGORY, or other key string in a package
1010space belonging to another organization. Device implementers MUST NOT alter or
1011extend any of the intent patterns used by the core apps listed in <a href="#heading=h.qiy4ddbiirgy">section 3.2.3.1</a>. Device implementations MAY include intent patterns using namespaces clearly
1012and obviously associated with their own organization. This prohibition is
1013analogous to that specified for Java language classes in <a href="#heading=h.blmhfmxlmvir">section 3.6</a>.</p>
1014
1015<h4 id=3_2_3_4_broadcast_intents>3.2.3.4. Broadcast Intents</h4>
1016
1017
1018<p>Third-party applications rely on the platform to broadcast certain intents to
1019notify them of changes in the hardware or software environment.
1020Android-compatible devices MUST broadcast the public broadcast intents in
1021response to appropriate system events. Broadcast intents are described in the
1022SDK documentation.</p>
1023
1024<h4 id=3_2_3_5_default_app_settings>3.2.3.5. Default App Settings</h4>
1025
1026
1027<p>Android includes settings that provide users an easy way to select their
1028default applications, for example for Home screen or SMS. Where it makes sense,
1029device implementations MUST provide a similar settings menu and be compatible
1030with the intent filter pattern and API methods described in the SDK
1031documentation as below.</p>
1032
1033<p>Device implementations:</p>
1034
1035<ul>
1036 <li> MUST honor the android.settings.HOME_SETTINGS intent to show a default app
1037settings menu for Home Screen, if the device implementation reports
1038android.software.home_screen [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a>
1039 <li> MUST provide a settings menu that will call the
1040android.provider.Telephony.ACTION_CHANGE_DEFAULT intent to show a dialog to
1041change the default SMS application, if the device implementation reports
1042android.hardware.telephony [<a href="https://developer.android.com/reference/android/provider/Telephony.Sms.Intents.html">Resources, 9</a>]
1043 <li> MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default
1044app settings menu for Tap and Pay, if the device implementation reports
1045android.hardware.nfc.hce [<a href="http://developer.android.com/reference/android/provider/Settings.html">Resources, 10]</a>
1046</ul>
1047
1048<h2 id=3_3_native_api_compatibility>3.3. Native API Compatibility</h2>
1049
1050
1051<h3 id=3_3_1_application_binary_interfaces>3.3.1 Application Binary Interfaces</h3>
1052
1053
1054<p>Managed Dalvik bytecode can call into native code provided in the application
1055.apk file as an ELF .so file compiled for the appropriate device hardware
1056architecture. As native code is highly dependent on the underlying processor
1057technology, Android defines a number of Application Binary Interfaces (ABIs) in
1058the Android NDK. Device implementations MUST be compatible with one or more
1059defined ABIs, and MUST implement compatibility with the Android NDK, as below.</p>
1060
1061<p>If a device implementation includes support for an Android ABI, it:</p>
1062
1063<ul>
1064 <li> MUST include support for code running in the managed environment to call into
1065native code, using the standard Java Native Interface (JNI) semantics
1066 <li> MUST be source-compatible (i.e. header compatible) and binary-compatible (for
1067the ABI) with each required library in the list below
1068 <li> MUST support the equivalent 32-bit ABI if any 64-bit ABI is supported
1069 <li> MUST accurately report the native Application Binary Interface (ABI) supported
1070by the device, via the android.os.Build.SUPPORTED_ABIS,
1071android.os.Build.SUPPORTED_32_BIT_ABIS, and
1072android.os.Build.SUPPORTED_64_BIT_ABIS parameters, each a comma separated list
1073of ABIs ordered from the most to the least preferred one
1074 <li> MUST report, via the above parameters, only those ABIs documented in the latest
1075version of the Android NDK, “NDK Programmer's Guide | ABI Management” in docs/
1076directory
1077 <li> SHOULD be built using the source code and header files available in the
1078upstream Android Open Source Project
1079</ul>
1080
1081<p>The following native code APIs MUST be available to apps that include native
1082code:</p>
1083
1084<ul>
1085 <li> libc (C library)
1086 <li> libm (math library)
1087 <li> Minimal support for C++
1088 <li> JNI interface
1089 <li> liblog (Android logging)
1090 <li> libz (Zlib compression)
1091 <li> libdl (dynamic linker)
1092 <li> libGLESv1_CM.so (OpenGL ES 1.x)
1093 <li> libGLESv2.so (OpenGL ES 2.0)
1094 <li> libGLESv3.so (OpenGL ES 3.x)
1095 <li> libEGL.so (native OpenGL surface management)
1096 <li> libjnigraphics.so
1097 <li> libOpenSLES.so (OpenSL ES 1.0.1 audio support)
1098 <li> libOpenMAXAL.so (OpenMAX AL 1.0.1 support)
1099 <li> libandroid.so (native Android activity support)
1100 <li> libmediandk.so (native media APIs support)
1101 <li> Support for OpenGL, as described below
1102</ul>
1103
1104<p>Note that future releases of the Android NDK may introduce support for
1105additional ABIs. If a device implementation is not compatible with an existing
1106predefined ABI, it MUST NOT report support for any ABIs at all.</p>
1107
1108<p>Note that device implementations MUST include libGLESv3.so and it MUST symlink
1109(symbolic link) to libGLESv2.so. in turn, MUST export all the OpenGL ES 3.1 and
1110Android 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
1111symbols must be present, only the corresponding functions for OpenGL ES
1112versions and extensions actually supported by the device must be fully
1113implemented.</p>
1114
1115<p>Native code compatibility is challenging. For this reason, device implementers
1116are <strong>very strongly encouraged</strong> to use the implementations of the libraries listed above from the upstream
1117Android Open Source Project. </p>
1118
1119<h2 id=3_4_web_compatibility>3.4. Web Compatibility</h2>
1120
1121
1122<h3 id=3_4_1_webview_compatibility>3.4.1. WebView Compatibility</h3>
1123
1124<table>
1125 <tr>
1126 <td class="tab2"></td>
1127 <td>
1128<p>The complete implementation of the android.webkit.Webview API MAY be provided
1129on Android Watch devices but MUST be provided on all other types of device
1130implementations.</p>
1131</td>
1132 </tr>
1133</table>
1134
1135
1136<p>The platform feature android.software.webview MUST be reported on any device
1137that provides a complete implementation of the android.webkit.WebView API, and
1138MUST NOT be reported on devices without a complete implementation of the API.
1139The Android Open Source implementation uses code from the Chromium Project to
1140implement 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
1141rendering system, device implementers MUST use the specific upstream build of
1142Chromium in the WebView implementation. Specifically:</p>
1143
1144<ul>
1145 <li> Device android.webkit.WebView implementations MUST be based on the Chromium
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]1146build from the upstream Android Open Source Project for Android 5.1. This build
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1147includes a specific set of functionality and security fixes for the WebView [<a href="http://www.chromium.org/">Resources, 13</a>].
1148 <li> The user agent string reported by the WebView MUST be in this format:
1149</ul>
1150
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]1151<p>Mozilla/5.1 (Linux; Android $(VERSION); $(MODEL) Build/$(BUILD))
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1152AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile
1153Safari/537.36</p>
1154 <ul>
1155 <li> The value of the $(VERSION) string MUST be the same as the value for
1156android.os.Build.VERSION.RELEASE.
1157 <li> The value of the $(MODEL) string MUST be the same as the value for
1158android.os.Build.MODEL.
1159 <li> The value of the $(BUILD) string MUST be the same as the value for
1160android.os.Build.ID.
1161 <li> The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the
1162upstream Android Open Source Project.
1163 <li> Device implementations MAY omit Mobile in the user agent string.
1164 </ul>
1165
1166<p>The WebView component SHOULD include support for as many HTML5 features as
1167possible and if it supports the feature SHOULD conform to the HTML5
1168specification [<a href="https://www.google.com/url?q=https%3A%2F%2Fhtml.spec.whatwg.org%2Fmultipage%2F&sa=D&sntz=1&usg=AFQjCNH7pPjEWho8n19H_n0ZXrQbI9RVlg">Resources, 14</a>].</p>
1169
1170<h3 id=3_4_2_browser_compatibility>3.4.2. Browser Compatibility</h3>
1171
1172<table>
1173 <tr>
1174 <td class="tab2"></td>
1175 <td>
1176<p>Android Television and Watch Devices MAY omit a browser application, but MUST
1177support the public intent patterns as described in <a href="#heading=h.qiy4ddbiirgy">section 3.2.3.1</a>. All other types of device implementations MUST include a standalone Browser
1178application for general user web browsing. </p>
1179</td>
1180 </tr>
1181</table>
1182
1183
1184<p>The standalone Browser MAY be based on a browser technology other than WebKit.
1185However, even if an alternate Browser application is used, the
1186android.webkit.WebView component provided to third-party applications MUST be
1187based on WebKit, as described in <a href="#heading=h.swqsalizdkk8">section 3.4.1</a>.</p>
1188
1189<p>Implementations MAY ship a custom user agent string in the standalone Browser
1190application.</p>
1191
1192<p>The standalone Browser application (whether based on the upstream WebKit
1193Browser application or a third-party replacement) SHOULD include support for as
1194much of HTML5 [<a href="https://www.google.com/url?q=https%3A%2F%2Fhtml.spec.whatwg.org%2Fmultipage%2F&sa=D&sntz=1&usg=AFQjCNH7pPjEWho8n19H_n0ZXrQbI9RVlg">Resources, 14</a>] as possible. Minimally, device implementations MUST support each of these
1195APIs associated with HTML5:</p>
1196
1197<ul>
1198 <li> application cache/offline operation [<a href="http://www.w3.org/html/wg/drafts/html/master/browsers.html#offline">Resources, 15</a>]
1199 <li> the <video> tag [<a href="http://www.w3.org/html/wg/drafts/html/master/embedded-content.html#video">Resources, 16</a>]
1200 <li> geolocation [<a href="http://www.w3.org/TR/geolocation-API/">Resources, 17</a>]
1201</ul>
1202
1203<p>Additionally, device implementations MUST support the HTML5/W3C webstorage API
1204[<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
1205IndexedDB over webstorage, IndexedDB is expected to become a required component
1206in a future version of Android.</p>
1207
1208<h2 id=3_5_api_behavioral_compatibility>3.5. API Behavioral Compatibility</h2>
1209
1210
1211<p>The behaviors of each of the API types (managed, soft, native, and web) must be
1212consistent with the preferred implementation of the upstream Android Open
1213Source Project [<a href="http://source.android.com/">Resources, 2</a>]. Some specific areas of compatibility are:</p>
1214
1215<ul>
1216 <li> Devices MUST NOT change the behavior or semantics of a standard intent.
1217 <li> Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular
1218type of system component (such as Service, Activity, ContentProvider, etc.).
1219 <li> Devices MUST NOT change the semantics of a standard permission.
1220</ul>
1221
1222<p>The above list is not comprehensive. The Compatibility Test Suite (CTS) tests
1223significant portions of the platform for behavioral compatibility, but not all.
1224It is the responsibility of the implementer to ensure behavioral compatibility
1225with the Android Open Source Project. For this reason, device implementers
1226SHOULD use the source code available via the Android Open Source Project where
1227possible, rather than re-implement significant parts of the system.</p>
1228
1229<h2 id=3_6_api_namespaces>3.6. API Namespaces</h2>
1230
1231
1232<p>Android follows the package and class namespace conventions defined by the Java
1233programming language. To ensure compatibility with third-party applications,
1234device implementers MUST NOT make any prohibited modifications (see below) to
1235these package namespaces:</p>
1236
1237<ul>
1238 <li> java.*
1239 <li> javax.*
1240 <li> sun.*
1241 <li> android.*
1242 <li> com.android.*
1243</ul>
1244
1245<p><strong>Prohibited modifications include</strong>:</p>
1246
1247<ul>
1248 <li> Device implementations MUST NOT modify the publicly exposed APIs on the Android
1249platform by changing any method or class signatures, or by removing classes or
1250class fields.
1251 <li> Device implementers MAY modify the underlying implementation of the APIs, but
1252such modifications MUST NOT impact the stated behavior and Java-language
1253signature of any publicly exposed APIs.
1254 <li> Device implementers MUST NOT add any publicly exposed elements (such as classes
1255or interfaces, or fields or methods to existing classes or interfaces) to the
1256APIs above.
1257</ul>
1258
1259<p>A "publicly exposed element” is any construct which is not decorated with the
1260"@hide" marker as used in the upstream Android source code. In other words,
1261device implementers MUST NOT expose new APIs or alter existing APIs in the
1262namespaces noted above. Device implementers MAY make internal-only
1263modifications, but those modifications MUST NOT be advertised or otherwise
1264exposed to developers.</p>
1265
1266<p>Device implementers MAY add custom APIs, but any such APIs MUST NOT be in a
1267namespace owned by or referring to another organization. For instance, device
1268implementers MUST NOT add APIs to the com.google.* or similar namespace: only
1269Google may do so. Similarly, Google MUST NOT add APIs to other companies'
1270namespaces. Additionally, if a device implementation includes custom APIs
1271outside the standard Android namespace, those APIs MUST be packaged in an
1272Android shared library so that only apps that explicitly use them (via the
1273<uses-library> mechanism) are affected by the increased memory usage of such
1274APIs.</p>
1275
1276<p>If a device implementer proposes to improve one of the package namespaces above
1277(such as by adding useful new functionality to an existing API, or adding a new
1278API), the implementer SHOULD visit <a href="https://source.android.com/">source.android.com</a> and begin the process for contributing changes and code, according to the
1279information on that site.</p>
1280
1281<p>Note that the restrictions above correspond to standard conventions for naming
1282APIs in the Java programming language; this section simply aims to reinforce
1283those conventions and make them binding through inclusion in this Compatibility
1284Definition.</p>
1285
1286<h2 id=3_7_runtime_compatibility>3.7. Runtime Compatibility</h2>
1287
1288
1289<p>Device implementations MUST support the full Dalvik Executable (DEX) format and
1290Dalvik 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
1291the Dalvik Executable Format, and the reference implementation's package
1292management system.</p>
1293
1294<p>Device implementations MUST configure Dalvik runtimes to allocate memory in
1295accordance with the upstream Android platform, and as specified by the
1296following table. (See <a href="#heading=h.6fey5v3qb5m3">section 7.1.1</a> for screen size and screen density definitions.)</p>
1297
1298<p>Note that memory values specified below are considered minimum values and
1299device implementations MAY allocate more memory per application.</p>
1300<table>
1301 <tr>
1302 <td class="tab0">
1303<p><strong>Screen Layout</strong></p>
1304</td>
1305 <td class="tab0">
1306<p><strong>Screen Density</strong></p>
1307</td>
1308 <td class="tab0">
1309<p><strong>Minimum Application Memory</strong></p>
1310</td>
1311 </tr>
1312 <tr>
1313 <td>
1314<p>small / normal</p>
1315</td>
1316 <td>
1317<p>120 dpi (ldpi) </p>
1318</td>
1319 <td>
1320<p>16MB</p>
1321</td>
1322 </tr>
1323 <tr>
1324 <td></td>
1325 <td>
1326<p>160 dpi (mdpi)</p>
1327</td>
1328 <td></td>
1329 </tr>
1330 <tr>
1331 <td></td>
1332 <td>
1333<p>213 dpi (tvdpi)</p>
1334</td>
1335 <td>
1336<p>32MB</p>
1337</td>
1338 </tr>
1339 <tr>
1340 <td></td>
1341 <td>
1342<p>240 dpi (hdpi)</p>
1343</td>
1344 <td></td>
1345 </tr>
1346 <tr>
1347 <td></td>
1348 <td>
Unsuk Jungaa55a672015-04-01 08:30:23 -0700[diff] [blame^]1349<p>280 dpi (280dpi)</p>
1350 </td>
1351 <td>
1352<p>48MB</p>
1353 </td>
1354 </tr>
1355 <tr>
1356 <td></td>
1357 <td>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1358<p>320 dpi (xhdpi)</p>
1359</td>
1360 <td>
1361<p>64MB</p>
1362</td>
1363 </tr>
1364 <tr>
1365 <td></td>
1366 <td>
1367<p>400 dpi (400dpi)</p>
1368</td>
1369 <td>
1370<p>96MB</p>
1371</td>
1372 </tr>
1373 <tr>
1374 <td></td>
1375 <td>
1376<p>480 dpi (xxhdpi)</p>
1377</td>
1378 <td>
1379<p>128MB</p>
1380</td>
1381 </tr>
1382 <tr>
1383 <td></td>
1384 <td>
1385<p>560 dpi (560dpi)</p>
1386</td>
1387 <td>
1388<p>192MB</p>
1389</td>
1390 </tr>
1391 <tr>
1392 <td></td>
1393 <td>
1394<p>640 dpi (xxxhdpi)</p>
1395</td>
1396 <td>
1397<p>256MB</p>
1398</td>
1399 </tr>
1400 <tr>
1401 <td>
1402<p>large</p>
1403</td>
1404 <td>
1405<p>120 dpi (ldpi) </p>
1406</td>
1407 <td>
1408<p>16MB</p>
1409</td>
1410 </tr>
1411 <tr>
1412 <td></td>
1413 <td>
1414<p>160 dpi (mdpi)</p>
1415</td>
1416 <td>
1417<p>32MB</p>
1418</td>
1419 </tr>
1420 <tr>
1421 <td></td>
1422 <td>
1423<p>213 dpi (tvdpi)</p>
1424</td>
1425 <td>
1426<p>64MB</p>
1427</td>
1428 </tr>
1429 <tr>
1430 <td></td>
1431 <td>
1432<p>240 dpi (hdpi)</p>
1433</td>
1434 <td></td>
1435 </tr>
1436 <tr>
1437 <td></td>
1438 <td>
Unsuk Jungaa55a672015-04-01 08:30:23 -0700[diff] [blame^]1439<p>280 dpi (280dpi)</p>
1440 </td>
1441 <td>
1442<p>96MB</p>
1443 </td>
1444 </tr>
1445 <tr>
1446 <td></td>
1447 <td>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1448<p>320 dpi (xhdpi)</p>
1449</td>
1450 <td>
1451<p>128MB</p>
1452</td>
1453 </tr>
1454 <tr>
1455 <td></td>
1456 <td>
1457<p>400 dpi (400dpi)</p>
1458</td>
1459 <td>
1460<p>192MB</p>
1461</td>
1462 </tr>
1463 <tr>
1464 <td></td>
1465 <td>
1466<p>480 dpi (xxhdpi)</p>
1467</td>
1468 <td>
1469<p>256MB</p>
1470</td>
1471 </tr>
1472 <tr>
1473 <td></td>
1474 <td>
1475<p>560 dpi (560dpi)</p>
1476</td>
1477 <td>
1478<p>384MB</p>
1479</td>
1480 </tr>
1481 <tr>
1482 <td></td>
1483 <td>
1484<p>640 dpi (xxxhdpi)</p>
1485</td>
1486 <td>
1487<p>512MB</p>
1488</td>
1489 </tr>
1490 <tr>
1491 <td>
1492<p>xlarge</p>
1493</td>
1494 <td>
1495<p>160 dpi (mdpi)</p>
1496</td>
1497 <td>
1498<p>64MB</p>
1499</td>
1500 </tr>
1501 <tr>
1502 <td></td>
1503 <td>
1504<p>213 dpi (tvdpi)</p>
1505</td>
1506 <td>
1507<p>96MB</p>
1508</td>
1509 </tr>
1510 <tr>
1511 <td></td>
1512 <td>
1513<p>240 dpi (hdpi)</p>
1514</td>
1515 <td></td>
1516 </tr>
1517 <tr>
1518 <td></td>
1519 <td>
Unsuk Jungaa55a672015-04-01 08:30:23 -0700[diff] [blame^]1520<p>280 dpi (280dpi)</p>
1521 </td>
1522 <td>
1523<p>144MB</p>
1524 </td>
1525 </tr>
1526 <tr>
1527 <td></td>
1528 <td>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1529<p>320 dpi (xhdpi)</p>
1530</td>
1531 <td>
1532<p>192MB</p>
1533</td>
1534 </tr>
1535 <tr>
1536 <td></td>
1537 <td>
1538<p>400 dpi (400dpi)</p>
1539</td>
1540 <td>
1541<p>288MB</p>
1542</td>
1543 </tr>
1544 <tr>
1545 <td></td>
1546 <td>
1547<p>480 dpi (xxhdpi)</p>
1548</td>
1549 <td>
1550<p>384MB</p>
1551</td>
1552 </tr>
1553 <tr>
1554 <td></td>
1555 <td>
1556<p>560 dpi (560dpi)</p>
1557</td>
1558 <td>
1559<p>576MB</p>
1560</td>
1561 </tr>
1562 <tr>
1563 <td></td>
1564 <td>
1565<p>640 dpi (xxxhdpi)</p>
1566</td>
1567 <td>
1568<p>768MB</p>
1569</td>
1570 </tr>
1571</table>
1572
1573
1574<h2 id=3_8_user_interface_compatibility>3.8. User Interface Compatibility</h2>
1575
1576
1577<h3 id=3_8_1_launcher_home_screen>3.8.1. Launcher (Home Screen)</h3>
1578
1579
1580<p>Android includes a launcher application (home screen) and support for
1581third-party applications to replace the device launcher (home screen). Device
1582implementations that allow third-party applications to replace the device home
1583screen MUST declare the platform feature android.software.home_screen.</p>
1584
1585<h3 id=3_8_2_widgets>3.8.2. Widgets</h3>
1586
1587<table>
1588 <tr>
1589 <td class="tab2"></td>
1590 <td>
1591<p>Widgets are optional for all Android device implementations, but SHOULD be
1592supported on Android Handheld devices.</p>
1593</td>
1594 </tr>
1595</table>
1596
1597
1598<p>Android defines a component type and corresponding API and lifecycle that
1599allows applications to expose an "AppWidget" 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
1600implementations. Device implementations that support embedding widgets on the
1601home screen MUST meet the following requirements and declare support for
1602platform feature android.software.app_widgets.</p>
1603
1604<ul>
1605 <li> Device launchers MUST include built-in support for AppWidgets, and expose user
1606interface affordances to add, configure, view, and remove AppWidgets directly
1607within the Launcher.
1608 <li> Device implementations MUST be capable of rendering widgets that are 4 x 4 in
1609the standard grid size. See the App Widget Design Guidelines in the Android SDK
1610documentation [<a href="http://developer.android.com/guide/practices/ui_guidelines/widget_design.html">Resources, 21</a>] for details.
1611 <li> Device implementations that include support for lock screen MAY support
1612application widgets on the lock screen.
1613</ul>
1614
1615<h3 id=3_8_3_notifications>3.8.3. Notifications</h3>
1616
1617
1618<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>
1619
1620<p>Some APIs allow applications to perform notifications or attract attention
1621using hardware—specifically sound, vibration, and light. Device implementations
1622MUST support notifications that use hardware features, as described in the SDK
1623documentation, and to the extent possible with the device implementation
1624hardware. For instance, if a device implementation includes a vibrator, it MUST
1625correctly implement the vibration APIs. If a device implementation lacks
1626hardware, the corresponding APIs MUST be implemented as no-ops. This behavior
1627is further detailed in <a href="#heading=h.5h5uvpadidzr">section 7</a>.</p>
1628
1629<p>Additionally, the implementation MUST correctly render all resources (icons,
1630sound files, etc.) provided for in the APIs [<a href="https://developer.android.com/guide/topics/resources/available-resources.html">Resources, 23</a>], or in the Status/System Bar icon style guide [<a href="http://developer.android.com/design/style/iconography.html">Resources, 24</a>]. Device implementers MAY provide an alternative user experience for
1631notifications than that provided by the reference Android Open Source
1632implementation; however, such alternative notification systems MUST support
1633existing notification resources, as above. </p>
1634
1635<p>Android includes support for various notifications, such as:</p>
1636
1637<ul>
1638 <li> <strong>Rich notifications</strong>—Interactive Views for ongoing notifications.
1639 <li> <strong>Heads-up notifications</strong>—Interactive Views users can act on or dismiss without leaving the current app.
1640 <li> <strong>Lockscreen notifications</strong>—Notifications shown over a lock screen with granular control on visibility.
1641</ul>
1642
1643<p>Device implementations MUST properly display and execute these notifications,
1644including the title/name, icon, text as documented in the Android APIs <a href="https://developer.android.com/design/patterns/notifications.html">[Resources, 25]</a>.</p>
1645
1646<p>Android includes Notification Listener Service APIs that allow apps (once
1647explicitly enabled by the user) to receive a copy of all notifications as they
1648are posted or updated. Device implementations MUST correctly and promptly send
1649notifications in their entirety to all such installed and user-enabled listener
1650services, including any and all metadata attached to the Notification object.</p>
1651
1652<h3 id=3_8_4_search>3.8.4. Search</h3>
1653
1654
1655<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
1656expose their application's data into the global system search. Generally
1657speaking, this functionality consists of a single, system-wide user interface
1658that allows users to enter queries, displays suggestions as users type, and
1659displays results. The Android APIs allow developers to reuse this interface to
1660provide search within their own apps, and allow developers to supply results to
1661the common global search user interface.</p>
1662
1663<p>Android device implementations SHOULD include global search, a single, shared,
1664system-wide search user interface capable of real-time suggestions in response
1665to user input. Device implementations SHOULD implement the APIs that allow
1666developers to reuse this user interface to provide search within their own
1667applications. Device implementations that implement the global search interface
1668MUST implement the APIs that allow third-party applications to add suggestions
1669to the search box when it is run in global search mode. If no third-party
1670applications are installed that make use of this functionality, the default
1671behavior SHOULD be to display web search engine results and suggestions.</p>
1672
1673<h3 id=3_8_5_toasts>3.8.5. Toasts</h3>
1674
1675
1676<p>Applications can use the "Toast" API to display short non-modal strings to the
1677end 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
1678some high-visibility manner.</p>
1679
1680<h3 id=3_8_6_themes>3.8.6. Themes</h3>
1681
1682
1683<p>Android provides "themes" as a mechanism for applications to apply styles
1684across an entire Activity or application.</p>
1685
1686<p>Android includes a "Holo" theme family as a set of defined styles for
1687application developers to use if they want to match the Holo theme look and
1688feel 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
1689exposed to applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1690
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]1691<p>Android includes a “Material” theme family as a set of defined styles for
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1692application developers to use if they want to match the design theme’s look and
1693feel across the wide variety of different Android device types. Device
1694implementations MUST support the “Material” theme family and MUST NOT alter any
1695of 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>
1696
1697<p>Android also includes a "Device Default" theme family as a set of defined
1698styles for application developers to use if they want to match the look and
1699feel of the device theme as defined by the device implementer. Device
1700implementations MAY modify the Device Default theme attributes exposed to
1701applications [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1702
1703<p>Android supports a new variant theme with translucent system bars, which allows
1704application developers to fill the area behind the status and navigation bar
1705with their app content. To enable a consistent developer experience in this
1706configuration, it is important the status bar icon style is maintained across
1707different device implementations. Therefore, Android device implementations
1708MUST use white for system status icons (such as signal strength and battery
1709level) and notifications issued by the system, unless the icon is indicating a
1710problematic status [<a href="http://developer.android.com/reference/android/R.style.html">Resources, 29</a>].</p>
1711
1712<h3 id=3_8_7_live_wallpapers>3.8.7. Live Wallpapers</h3>
1713
1714
1715<p>Android defines a component type and corresponding API and lifecycle that
1716allows applications to expose one or more "Live Wallpapers" 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
1717input capabilities that display as a wallpaper, behind other applications.</p>
1718
1719<p>Hardware is considered capable of reliably running live wallpapers if it can
1720run all live wallpapers, with no limitations on functionality, at a reasonable
1721frame rate with no adverse effects on other applications. If limitations in the
1722hardware cause wallpapers and/or applications to crash, malfunction, consume
1723excessive CPU or battery power, or run at unacceptably low frame rates, the
1724hardware is considered incapable of running live wallpaper. As an example, some
1725live wallpapers may use an OpenGL 2.0 or 3.x context to render their content.
1726Live wallpaper will not run reliably on hardware that does not support multiple
1727OpenGL contexts because the live wallpaper use of an OpenGL context may
1728conflict with other applications that also use an OpenGL context.</p>
1729
1730<p>Device implementations capable of running live wallpapers reliably as described
1731above SHOULD implement live wallpapers, and when implemented MUST report the
1732platform feature flag android.software.live_wallpaper.</p>
1733
1734<h3 id=3_8_8_activity_switching>3.8.8. Activity Switching</h3>
1735
1736<table>
1737 <tr>
1738 <td class="tab2"></td>
1739 <td>
1740<p>As the Recent function navigation key is OPTIONAL, the requirements to
1741implement the overview screen is OPTIONAL for Android Television devices and
1742Android Watch devices.</p>
1743</td>
1744 </tr>
1745</table>
1746
1747
1748<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
1749accessed activities and tasks using a thumbnail image of the application's
1750graphical state at the moment the user last left the application. Device
1751implementations including the recents function navigation key as detailed in <a href="#heading=h.dzfhwcjzm5z6">section 7.2.3</a>, MAY alter the interface but MUST meet the following requirements:</p>
1752
1753<ul>
1754 <li> MUST display affiliated recents as a group that moves together
1755 <li> MUST support at least up to 20 displayed activities
1756 <li> MUST at least display the title of 4 activities at a time
1757 <li> SHOULD display highlight color, icon, screen title in recents
1758 <li> MUST implement the screen pinning behavior [<a href="https://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
1759 <li> SHOULD display a closing affordance ("x") but MAY delay this until user
1760interacts with screens
1761</ul>
1762
1763<p>Device implementations are STRONGLY ENCOURAGED to use the upstream Android user
1764interface (or a similar thumbnail-based interface) for the overview screen.</p>
1765
1766<h3 id=3_8_9_input_management>3.8.9. Input Management</h3>
1767
1768
1769<p>Android includes support for Input Management and support for third-party input
1770method 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
1771the device MUST declare the platform feature android.software.input_methods and
1772support IME APIs as defined in the Android SDK documentation.</p>
1773
1774<p>Device implementations that declare the android.software.input_methods feature
1775MUST provide a user-accessible mechanism to add and configure third-party input
1776methods. Device implementations MUST display the settings interface in response
1777to the android.settings.INPUT_METHOD_SETTINGS intent.</p>
1778
1779<h3 id=3_8_10_lock_screen_media_control>3.8.10. Lock Screen Media Control</h3>
1780
1781
1782<p>The Remote Control Client API is deprecated from Android 5.0 in favor of the
1783Media Notification Template that allows media applications to integrate with
1784playback controls that are displayed on the lock screen [<a href="https://developer.android.com/reference/android/app/Notification.MediaStyle.html">Resources, 35</a>]. Device implementations that support a lock screen in the device MUST support
1785the Media Notification Template along with other notifications.</p>
1786
1787<h3 id=3_8_11_dreams>3.8.11. Dreams</h3>
1788
1789
1790<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
1791a power source is idle or docked in a desk dock. Android Watch devices MAY
1792implement Dreams, but other types of device implementations SHOULD include
1793support for Dreams and provide a settings option for users to configure Dreams
1794in response to the android.settings.DREAM_SETTINGS intent.</p>
1795
1796<h3 id=3_8_12_location>3.8.12. Location</h3>
1797
1798
1799<p>When a device has a hardware sensor (e.g. GPS) that is capable of providing the
1800location coordinates, location modes MUST be displayed in the Location menu
1801within Settings [<a href="http://developer.android.com/reference/android/provider/Settings.Secure.html#LOCATION_MODE">Resources, 37</a>]. </p>
1802
1803<h3 id=3_8_13_unicode_and_font>3.8.13. Unicode and Font</h3>
1804
1805
1806<p>Android includes support for color emoji characters. When Android device
1807implementations include an IME, devices MUST provide an input method to the
1808user 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
1809glyph.</p>
1810
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]1811<p>Android includes support for Roboto 2 font with different
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]1812weights—sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black,
1813sans-serif-condensed, sans-serif-condensed-light—which MUST all be included for
1814the languages available on the device and full Unicode 7.0 coverage of Latin,
1815Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and
1816all glyphs in the currency symbols block of Unicode 7.0.</p>
1817
1818<h2 id=3_9_device_administration>3.9. Device Administration</h2>
1819
1820
1821<p>Android includes features that allow security-aware applications to perform
1822device administration functions at the system level, such as enforcing password
1823policies or performing remote wipe, through the Android Device Administration
1824API [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>]. Device implementations MUST provide an implementation of the
1825DevicePolicyManager class [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html">Resources, 40</a>]. Device implementations that include support for lock screen MUST support the
1826full range of device administration policies defined in the Android SDK
1827documentation [<a href="http://developer.android.com/guide/topics/admin/device-admin.html">Resources, 39</a>] and report the platform feature android.software.device_admin.</p>
1828
1829<p>Device implementations MAY have a preinstalled application performing device
1830administration functions but this application MUST NOT be set out-of-the box as
1831the default Device Owner app [<a href="http://developer.android.com/reference/android/app/admin/DevicePolicyManager.html#isDeviceOwnerApp(java.lang.String)">Resources, 41</a>].</p>
1832
1833<h2 id=3_10_accessibility>3.10. Accessibility</h2>
1834
1835
1836<p>Android provides an accessibility layer that helps users with disabilities to
1837navigate their devices more easily. In addition, Android provides platform APIs
1838that enable accessibility service implementations to receive callbacks for user
1839and system events and generate alternate feedback mechanisms, such as
1840text-to-speech, haptic feedback, and trackball/d-pad navigation [<a href="http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html">Resources, 42</a>]. Device implementations MUST provide an implementation of the Android
1841accessibility framework consistent with the default Android implementation.
1842Device implementations MUST meet the following requirements:</p>
1843
1844<ul>
1845 <li> MUST support third-party accessibility service implementations through the
1846android.accessibilityservice APIs [<a href="http://developer.android.com/reference/android/view/accessibility/package-summary.html">Resources, 43</a>]
1847 <li> MUST generate AccessibilityEvents and deliver these events to all registered
1848AccessibilityService implementations in a manner consistent with the default
1849Android implementation
1850 <li> Unless an Android Watch device with no audio output, device implementations
1851MUST provide a user-accessible mechanism to enable and disable accessibility
1852services, and MUST display this interface in response to the
1853android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS intent.
1854</ul>
1855
1856<p>Additionally, device implementations SHOULD provide an implementation of an
1857accessibility service on the device, and SHOULD provide a mechanism for users
1858to enable the accessibility service during device setup. An open source
1859implementation of an accessibility service is available from the Eyes Free
1860project [<a href="https://code.google.com/p/eyes-free/">Resources, 44</a>].</p>
1861
1862<h2 id=3_11_text-to-speech>3.11. Text-to-Speech</h2>
1863
1864
1865<p>Android includes APIs that allow applications to make use of text-to-speech
1866(TTS) services and allows service providers to provide implementations of TTS
1867services [<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
1868MUST meet these requirements related to the Android TTS framework. </p>
1869
1870<p>Device implementations:</p>
1871
1872<ul>
1873 <li> MUST support the Android TTS framework APIs and SHOULD include a TTS engine
1874supporting the languages available on the device. Note that the upstream
1875Android open source software includes a full-featured TTS engine
1876implementation.
1877 <li> MUST support installation of third-party TTS engines
1878 <li> MUST provide a user-accessible interface that allows users to select a TTS
1879engine for use at the system level
1880</ul>
1881
1882<h2 id=3_12_tv_input_framework>3.12. TV Input Framework</h2>
1883
1884
1885<p>The Android Television Input Framework (TIF) simplifies the delivery of live
1886content to Android Television devices. TIF provides a standard API to create
1887input modules that control Android Television devices. Android Television
1888device implementations MUST support Television Input Framework [<a href="https://source.android.com/devices/tv/index.html">Resources, 46</a>].</p>
1889
1890<p>Device implementations that support TIF MUST declare the platform feature
1891android.software.live_tv. </p>
1892
1893<h1 id=4_application_packaging_compatibility>4. Application Packaging Compatibility</h1>
1894
1895
1896<p>Device implementations MUST install and run Android ".apk" files as generated
1897by the "aapt" tool included in the official Android SDK [<a href="http://developer.android.com/guide/developing/tools/index.html">Resources, 47</a>].</p>
1898
1899<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
1900files from installing and running correctly on other compatible devices</p>
1901
1902<h1 id=5_multimedia_compatibility>5. Multimedia Compatibility</h1>
1903
1904
1905<h2 id=5_1_media_codecs>5.1. Media Codecs</h2>
1906
1907
1908<p>Device implementations MUST support the core media formats specified in the
1909Android 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
1910implementations MUST support the media formats, encoders, decoders, file types,
1911and container formats defined in the tables below. All of these codecs are
1912provided as software implementations in the preferred Android implementation
1913from the Android Open Source Project.</p>
1914
1915<p>Please note that neither Google nor the Open Handset Alliance make any
1916representation that these codecs are free from third-party patents. Those
1917intending to use this source code in hardware or software products are advised
1918that implementations of this code, including in open source software or
1919shareware, may require patent licenses from the relevant patent holders.</p>
1920
1921<h3 id=5_1_1_audio_codecs>5.1.1. Audio Codecs</h3>
1922
1923<table>
1924 <tr>
1925 <td class="tab0">
1926<p><strong>Format / Codec</strong></p>
1927</td>
1928 <td class="tab0">
1929<p><strong>Encoder</strong></p>
1930</td>
1931 <td class="tab0">
1932<p><strong>Decoder</strong></p>
1933</td>
1934 <td class="tab0">
1935<p><strong>Details</strong></p>
1936</td>
1937 <td class="tab0">
1938<p><strong>Supported File Type(s) / Container Formats</strong></p>
1939</td>
1940 </tr>
1941 <tr>
1942 <td class="tab3">
1943<p>MPEG-4 AAC Profile</p>
1944
1945<p>(AAC LC)</p>
1946</td>
1947 <td class="tab3">
1948<p>REQUIRED1</p>
1949</td>
1950 <td class="tab3">
1951<p>REQUIRED</p>
1952</td>
1953 <td class="tab3">
1954<p>Support for mono/stereo/5.0/5.12 content with standard sampling rates from 8 to
195548 kHz.</p>
1956</td>
1957 <td class="tab4">
1958<p>• 3GPP (.3gp)</p>
1959
1960<p>• MPEG-4 (.mp4, .m4a)</p>
1961
1962<p>• ADTS raw AAC (.aac, decode in Android 3.1+, encode in Android 4.0+, ADIF not
1963supported)</p>
1964
1965<p>• MPEG-TS (.ts, not seekable, Android 3.0+)</p>
1966</td>
1967 </tr>
1968 <tr>
1969 <td class="tab3">
1970<p>MPEG-4 HE AAC Profile (AAC+)</p>
1971</td>
1972 <td>
1973<p>REQUIRED1</p>
1974
1975<p>(Android 4.1+)</p>
1976</td>
1977 <td class="tab3">
1978<p>REQUIRED</p>
1979</td>
1980 <td class="tab3">
1981<p>Support for mono/stereo/5.0/5.12 content with standard sampling rates from 16
1982to 48 kHz.</p>
1983</td>
1984 <td class="tab4"></td>
1985 </tr>
1986 <tr>
1987 <td class="tab3">
1988<p>MPEG-4 HE AACv2</p>
1989
1990<p>Profile (enhanced AAC+)</p>
1991</td>
1992 <td class="tab3">
1993<p> </p>
1994</td>
1995 <td class="tab3">
1996<p>REQUIRED</p>
1997</td>
1998 <td class="tab3">
1999<p>Support for mono/stereo/5.0/5.12 content with standard sampling rates from 16
2000to 48 kHz.</p>
2001</td>
2002 <td class="tab4"></td>
2003 </tr>
2004 <tr>
2005 <td class="tab3">
2006<p>AAC ELD (enhanced low delay AAC)</p>
2007</td>
2008 <td>
2009<p>REQUIRED1 </p>
2010
2011<p>(Android 4.1+)</p>
2012</td>
2013 <td>
2014<p>REQUIRED</p>
2015
2016<p>(Android 4.1+)</p>
2017</td>
2018 <td class="tab3">
2019<p>Support for mono/stereo content with standard sampling rates from 16 to 48 kHz.</p>
2020</td>
2021 <td class="tab4"></td>
2022 </tr>
2023 <tr>
2024 <td class="tab3">
2025<p>AMR-NB</p>
2026</td>
2027 <td class="tab3">
2028<p>REQUIRED3</p>
2029</td>
2030 <td class="tab3">
2031<p>REQUIRED3</p>
2032</td>
2033 <td class="tab3">
2034<p>4.75 to 12.2 kbps sampled @ 8kHz</p>
2035</td>
2036 <td class="tab4">
2037<p>3GPP (.3gp)</p>
2038</td>
2039 </tr>
2040 <tr>
2041 <td class="tab3">
2042<p>AMR-WB</p>
2043</td>
2044 <td class="tab3">
2045<p>REQUIRED3 </p>
2046</td>
2047 <td class="tab3">
2048<p>REQUIRED3</p>
2049</td>
2050 <td class="tab3">
2051<p>9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16kHz</p>
2052</td>
2053 <td class="tab4"></td>
2054 </tr>
2055 <tr>
2056 <td class="tab3">
2057<p>FLAC</p>
2058</td>
2059 <td class="tab3">
2060<p> </p>
2061</td>
2062 <td>
2063<p>REQUIRED</p>
2064
2065<p>(Android 3.1+)</p>
2066</td>
2067 <td class="tab3">
2068<p>Mono/Stereo (no multichannel). Sample rates up to 48 kHz (but up to 44.1 kHz is
2069recommended on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler
2070does not include a low-pass filter). 16-bit recommended; no dither applied for
207124-bit.</p>
2072</td>
2073 <td class="tab3">
2074<p>FLAC (.flac) only</p>
2075</td>
2076 </tr>
2077 <tr>
2078 <td class="tab3">
2079<p>MP3</p>
2080</td>
2081 <td class="tab3">
2082<p> </p>
2083</td>
2084 <td class="tab3">
2085<p>REQUIRED</p>
2086</td>
2087 <td>
2088<p>Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR)</p>
2089</td>
2090 <td class="tab3">
2091<p>MP3 (.mp3)</p>
2092</td>
2093 </tr>
2094 <tr>
2095 <td class="tab3">
2096<p>MIDI</p>
2097</td>
2098 <td class="tab3">
2099<p> </p>
2100</td>
2101 <td class="tab3">
2102<p>REQUIRED</p>
2103</td>
2104 <td class="tab3">
2105<p>MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for
2106ringtone formats RTTTL/RTX, OTA, and iMelody</p>
2107</td>
2108 <td class="tab3">
2109<p>• Type 0 and 1 (.mid, .xmf, .mxmf)</p>
2110
2111<p>• RTTTL/RTX (.rtttl, .rtx)</p>
2112
2113<p>• OTA (.ota)</p>
2114
2115<p>• iMelody (.imy)</p>
2116</td>
2117 </tr>
2118 <tr>
2119 <td class="tab3">
2120<p>Vorbis</p>
2121</td>
2122 <td class="tab3">
2123<p> </p>
2124</td>
2125 <td class="tab3">
2126<p>REQUIRED</p>
2127</td>
2128 <td class="tab3">
2129<p> </p>
2130</td>
2131 <td class="tab3">
2132<p>• Ogg (.ogg)</p>
2133
2134<p>• Matroska (.mkv, Android 4.0+)</p>
2135</td>
2136 </tr>
2137 <tr>
2138 <td class="tab3">
2139<p>PCM/WAVE</p>
2140</td>
2141 <td>
2142<p>REQUIRED4</p>
2143
2144<p>(Android 4.1+)</p>
2145</td>
2146 <td class="tab3">
2147<p>REQUIRED</p>
2148</td>
2149 <td class="tab3">
2150<p>16-bit linear PCM (rates up to limit of hardware). Devices MUST support
2151sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz
2152frequencies.</p>
2153</td>
2154 <td class="tab3">
2155<p>WAVE (.wav)</p>
2156</td>
2157 </tr>
2158 <tr>
2159 <td class="tab3">
2160<p>Opus</p>
2161</td>
2162 <td class="tab3"></td>
2163 <td class="tab3">
2164<p>REQUIRED</p>
2165
2166<p>(Android 5.0+)</p>
2167</td>
2168 <td class="tab3"></td>
2169 <td class="tab3">
2170<p>Matroska (.mkv)</p>
2171</td>
2172 </tr>
2173</table>
2174
2175
2176<p>1 Required for device implementations that define android.hardware.microphone
2177but optional for Android Watch device implementations.</p>
2178
2179<p>2 Only downmix of 5.0/5.1 content is required; recording or rendering more than
21802 channels is optional.</p>
2181
2182<p>3 Required for Android Handheld device implementations. </p>
2183
2184<p>4 Required for device implementations that define android.hardware.microphone,
2185including Android Watch device implementations.</p>
2186
2187<h3 id=5_1_2_image_codecs>5.1.2. Image Codecs</h3>
2188
2189<table>
2190 <tr>
2191 <td class="tab0">
2192<p><strong>Format / Codec</strong></p>
2193</td>
2194 <td class="tab0">
2195<p><strong>Encoder</strong></p>
2196</td>
2197 <td class="tab0">
2198<p><strong>Decoder</strong></p>
2199</td>
2200 <td class="tab0">
2201<p><strong>Details</strong></p>
2202</td>
2203 <td class="tab0">
2204<p><strong>Supported File Type(s) / Container Formats</strong></p>
2205</td>
2206 </tr>
2207 <tr>
2208 <td class="tab3">
2209<p>JPEG</p>
2210</td>
2211 <td class="tab3">
2212<p>REQUIRED</p>
2213</td>
2214 <td class="tab3">
2215<p>REQUIRED</p>
2216</td>
2217 <td class="tab3">
2218<p>Base+progressive</p>
2219</td>
2220 <td class="tab3">
2221<p>JPEG (.jpg)</p>
2222</td>
2223 </tr>
2224 <tr>
2225 <td class="tab3">
2226<p>GIF</p>
2227</td>
2228 <td class="tab3">
2229<p> </p>
2230</td>
2231 <td class="tab3">
2232<p>REQUIRED</p>
2233</td>
2234 <td class="tab3">
2235<p> </p>
2236</td>
2237 <td class="tab3">
2238<p>GIF (.gif)</p>
2239</td>
2240 </tr>
2241 <tr>
2242 <td class="tab3">
2243<p>PNG</p>
2244</td>
2245 <td class="tab3">
2246<p>REQUIRED</p>
2247</td>
2248 <td class="tab3">
2249<p>REQUIRED</p>
2250</td>
2251 <td class="tab3">
2252<p> </p>
2253</td>
2254 <td class="tab3">
2255<p>PNG (.png)</p>
2256</td>
2257 </tr>
2258 <tr>
2259 <td class="tab3">
2260<p>BMP</p>
2261</td>
2262 <td class="tab3">
2263<p> </p>
2264</td>
2265 <td class="tab3">
2266<p>REQUIRED</p>
2267</td>
2268 <td class="tab3">
2269<p> </p>
2270</td>
2271 <td class="tab3">
2272<p>BMP (.bmp)</p>
2273</td>
2274 </tr>
2275 <tr>
2276 <td class="tab3">
2277<p>WebP</p>
2278</td>
2279 <td class="tab3">
2280<p>REQUIRED</p>
2281</td>
2282 <td class="tab3">
2283<p>REQUIRED</p>
2284</td>
2285 <td class="tab3">
2286<p> </p>
2287</td>
2288 <td class="tab3">
2289<p>WebP (.webp)</p>
2290</td>
2291 </tr>
2292</table>
2293
2294
2295<h3 id=5_1_3_video_codecs>5.1.3. Video Codecs</h3>
2296
2297<table>
2298 <tr>
2299 <td class="tab2"></td>
2300 <td>
2301<p>Video codecs are optional for Android Watch device implementations.</p>
2302</td>
2303 </tr>
2304</table>
2305
2306<table>
2307 <tr>
2308 <td class="tab0">
2309<p><strong>Format / Codec</strong></p>
2310</td>
2311 <td class="tab0">
2312<p><strong>Encoder</strong></p>
2313</td>
2314 <td class="tab0">
2315<p><strong>Decoder</strong></p>
2316</td>
2317 <td class="tab0">
2318<p><strong>Details</strong></p>
2319</td>
2320 <td class="tab0">
2321<p><strong>Supported File Type(s) / Container Formats</strong></p>
2322</td>
2323 </tr>
2324 <tr>
2325 <td class="tab3">
2326<p>H.263</p>
2327</td>
2328 <td class="tab3">
2329<p>REQUIRED1</p>
2330</td>
2331 <td class="tab3">
2332<p>REQUIRED2</p>
2333</td>
2334 <td class="tab3">
2335<p> </p>
2336</td>
2337 <td class="tab3">
2338<p>• 3GPP (.3gp)</p>
2339
2340<p>• MPEG-4 (.mp4)</p>
2341</td>
2342 </tr>
2343 <tr>
2344 <td class="tab3">
2345<p>H.264 AVC</p>
2346</td>
2347 <td class="tab3">
2348<p>REQUIRED2</p>
2349</td>
2350 <td class="tab3">
2351<p>REQUIRED2</p>
2352</td>
2353 <td>
2354<p>See <a href="#heading=h.be1ledetmole">section 5.2 </a>and <a href="#heading=h.ogx7l5t9zub6">5.3</a> for details</p>
2355</td>
2356 <td class="tab3">
2357<p>• 3GPP (.3gp)</p>
2358
2359<p>• MPEG-4 (.mp4)</p>
2360
2361<p>• MPEG-TS (.ts, AAC audio only, not seekable, Android 3.0+)</p>
2362</td>
2363 </tr>
2364 <tr>
2365 <td class="tab3">
2366<p>H.265 HEVC</p>
2367</td>
2368 <td class="tab3"></td>
2369 <td class="tab3">
2370<p>REQUIRED2</p>
2371</td>
2372 <td>
2373<p>See <a href="#heading=h.be1ledetmole">section 5.3</a> for details</p>
2374</td>
2375 <td class="tab3">
2376<p>MPEG-4 (.mp4)</p>
2377</td>
2378 </tr>
2379 <tr>
2380 <td class="tab3">
2381<p>MPEG-4 SP</p>
2382</td>
2383 <td class="tab3">
2384<p> </p>
2385</td>
2386 <td class="tab3">
2387<p>REQUIRED2</p>
2388</td>
2389 <td class="tab3">
2390<p> </p>
2391</td>
2392 <td class="tab3">
2393<p>3GPP (.3gp)</p>
2394</td>
2395 </tr>
2396 <tr>
2397 <td class="tab3">
2398<p>VP83</p>
2399</td>
2400 <td>
2401<p>REQUIRED2</p>
2402
2403<p>(Android 4.3+)</p>
2404</td>
2405 <td>
2406<p>REQUIRED2</p>
2407
2408<p>(Android 2.3.3+)</p>
2409</td>
2410 <td>
2411<p>See <a href="#heading=h.be1ledetmole">section 5.2</a> and <a href="#heading=h.ogx7l5t9zub6">5.3</a> for details</p>
2412</td>
2413 <td>
2414<p>• WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 110</a>]</p>
2415
2416<p>• Matroska (.mkv, Android 4.0+)4</p>
2417</td>
2418 </tr>
2419 <tr>
2420 <td class="tab3">
2421<p>VP9</p>
2422</td>
2423 <td class="tab3"></td>
2424 <td class="tab3">
2425<p>REQUIRED2</p>
2426
2427<p>(Android 4.4+)</p>
2428</td>
2429 <td>
2430<p>See <a href="#heading=h.be1ledetmole">section 5.</a><u>3</u> for details</p>
2431</td>
2432 <td>
2433<p>• WebM (.webm) [<a href="http://www.webmproject.org/">Resources, 110</a>]</p>
2434
2435<p>• Matroska (.mkv, Android 4.0+)4</p>
2436</td>
2437 </tr>
2438</table>
2439
2440
2441<p>1 Required for device implementations that include camera hardware and define
2442android.hardware.camera or android.hardware.camera.front.</p>
2443
2444<p>2 Required for device implementations except Android Watch devices. </p>
2445
2446<p>3 For acceptable quality of web video streaming and video-conference services,
2447device implementations SHOULD use a hardware VP8 codec that meets the
2448requirements in [<a href="http://www.webmproject.org/hardware/rtc-coding-requirements/">Resources, 51</a>].</p>
2449
2450<p>4 Device implementations SHOULD support writing Matroska WebM files.</p>
2451
2452<h2 id=5_2_video_encoding>5.2. Video Encoding</h2>
2453
2454<table>
2455 <tr>
2456 <td class="tab2"></td>
2457 <td>
2458<p>Video codecs are optional for Android Watch device implementations.</p>
2459</td>
2460 </tr>
2461</table>
2462
2463
2464<p>Android device implementations with H.264 codec support, MUST support Baseline
2465Profile Level 3 and the following SD (Standard Definition) video encoding
2466profiles and SHOULD support Main Profile Level 4 and the following HD (High
2467Definition) video encoding profiles. Android Television devices are STRONGLY
2468RECOMMENDED to encode HD 1080p video at 30 fps.</p>
2469<table>
2470 <tr>
2471 <td class="tab0"></td>
2472 <td class="tab0">
2473<p><strong>SD (Low quality)</strong></p>
2474</td>
2475 <td class="tab0">
2476<p><strong>SD (High quality)</strong></p>
2477</td>
2478 <td class="tab0">
2479<p><strong>HD 720p1</strong></p>
2480</td>
2481 <td class="tab0">
2482<p><strong>HD 1080p1</strong></p>
2483</td>
2484 </tr>
2485 <tr>
2486 <td>
2487<p><strong> Video resolution</strong></p>
2488</td>
2489 <td class="tab3">
2490<p>320 x 240 px</p>
2491</td>
2492 <td class="tab3">
2493<p>720 x 480 px</p>
2494</td>
2495 <td class="tab3">
2496<p>1280 x 720 px</p>
2497</td>
2498 <td>
2499<p>1920 x 1080 px</p>
2500</td>
2501 </tr>
2502 <tr>
2503 <td>
2504<p><strong> Video frame rate</strong></p>
2505</td>
2506 <td class="tab3">
2507<p>20 fps</p>
2508</td>
2509 <td class="tab3">
2510<p>30 fps</p>
2511</td>
2512 <td class="tab3">
2513<p>30 fps</p>
2514</td>
2515 <td>
2516<p>30 fps</p>
2517</td>
2518 </tr>
2519 <tr>
2520 <td>
2521<p><strong> Video bitrate</strong></p>
2522</td>
2523 <td class="tab3">
2524<p>384 Kbps</p>
2525</td>
2526 <td class="tab3">
2527<p>2 Mbps</p>
2528</td>
2529 <td class="tab3">
2530<p>4 Mbps</p>
2531</td>
2532 <td>
2533<p>10 Mbps</p>
2534</td>
2535 </tr>
2536</table>
2537
2538
2539<p>1 When supported by hardware, but STRONGLY RECOMMENDED for Android Television
2540devices.</p>
2541
2542<p>Android device implementations with VP8 codec support MUST support the SD video
2543encoding profiles and SHOULD support the following HD (High Definition) video
2544encoding profiles.</p>
2545<table>
2546 <tr>
2547 <td class="tab0"></td>
2548 <td class="tab0">
2549<p><strong>SD (Low quality)</strong></p>
2550</td>
2551 <td class="tab0">
2552<p><strong>SD (High quality)</strong></p>
2553</td>
2554 <td class="tab0">
2555<p><strong>HD 720p1</strong></p>
2556</td>
2557 <td class="tab0">
2558<p><strong>HD 1080p1</strong></p>
2559</td>
2560 </tr>
2561 <tr>
2562 <td>
2563<p><strong>Video resolution</strong></p>
2564</td>
2565 <td>
2566<p>320 x 180 px</p>
2567</td>
2568 <td>
2569<p>640 x 360 px</p>
2570</td>
2571 <td>
2572<p>1280 x 720 px</p>
2573</td>
2574 <td>
2575<p>1920 x 1080 px</p>
2576</td>
2577 </tr>
2578 <tr>
2579 <td>
2580<p><strong>Video frame rate</strong></p>
2581</td>
2582 <td>
2583<p>30 fps</p>
2584</td>
2585 <td>
2586<p>30 fps</p>
2587</td>
2588 <td>
2589<p>30 fps</p>
2590</td>
2591 <td>
2592<p>30 fps</p>
2593</td>
2594 </tr>
2595 <tr>
2596 <td>
2597<p><strong>Video bitrate</strong></p>
2598</td>
2599 <td>
2600<p>800 Kbps </p>
2601</td>
2602 <td>
2603<p>2 Mbps</p>
2604</td>
2605 <td>
2606<p>4 Mbps</p>
2607</td>
2608 <td>
2609<p>10 Mbps</p>
2610</td>
2611 </tr>
2612</table>
2613
2614
2615<p>1 When supported by hardware.</p>
2616
2617<h2 id=5_3_video_decoding>5.3. Video Decoding</h2>
2618
2619<table>
2620 <tr>
2621 <td class="tab2"></td>
2622 <td>
2623<p>Video codecs are optional for Android Watch device implementations.</p>
2624</td>
2625 </tr>
2626</table>
2627
2628
2629<p>Device implementations MUST support dynamic video resolution switching within
2630the same stream for VP8, VP9 ,H.264, and H.265 codecs.</p>
2631
2632<p>Android device implementations with H.264 decoders, MUST support Baseline
2633Profile Level 3 and the following SD video decoding profiles and SHOULD support
2634the HD decoding profiles. Android Television devices MUST support High Profile
2635Level 4.2 and the HD 1080p decoding profile.</p>
2636<table>
2637 <tr>
2638 <td class="tab0"></td>
2639 <td class="tab0">
2640<p><strong>SD (Low quality)</strong></p>
2641</td>
2642 <td class="tab0">
2643<p><strong>SD (High quality)</strong></p>
2644</td>
2645 <td class="tab0">
2646<p><strong>HD 720p1</strong></p>
2647</td>
2648 <td class="tab0">
2649<p><strong>HD 1080p1</strong></p>
2650</td>
2651 </tr>
2652 <tr>
2653 <td>
2654<p><strong>Video resolution</strong></p>
2655</td>
2656 <td>
2657<p>320 x 240 px</p>
2658</td>
2659 <td>
2660<p>720 x 480 px</p>
2661</td>
2662 <td>
2663<p>1280 x 720 px</p>
2664</td>
2665 <td>
2666<p>1920 x 1080 px</p>
2667</td>
2668 </tr>
2669 <tr>
2670 <td>
2671<p><strong>Video frame rate</strong></p>
2672</td>
2673 <td>
2674<p>30 fps</p>
2675</td>
2676 <td>
2677<p>30 fps</p>
2678</td>
2679 <td>
2680<p>30 fps / 60 fps2</p>
2681</td>
2682 <td>
2683<p>30 fps / 60 fps2</p>
2684</td>
2685 </tr>
2686 <tr>
2687 <td></td>
2688 <td></td>
2689 <td></td>
2690 <td></td>
2691 <td></td>
2692 </tr>
2693 <tr>
2694 <td>
2695<p><strong>Video bitrate</strong></p>
2696</td>
2697 <td>
2698<p>800 Kbps </p>
2699</td>
2700 <td>
2701<p>2 Mbps</p>
2702</td>
2703 <td>
2704<p>8 Mbps</p>
2705</td>
2706 <td>
2707<p>20 Mbps</p>
2708</td>
2709 </tr>
2710</table>
2711
2712
2713<p>1 Required for Android Television device implementations, but for other device
2714types only when supported by hardware.</p>
2715
2716<p>2 Required for Android Television device implementations.</p>
2717
2718<p>Android device implementations when supporting VP8 codec as described in <a href="#heading=h.hitn8abpwkj2">section 5.1.3</a>, MUST support the following SD decoding profiles and SHOULD support the HD
2719decoding profiles. Android Television devices MUST support the HD 1080p
2720decoding profile. </p>
2721<table>
2722 <tr>
2723 <td class="tab0"></td>
2724 <td class="tab0">
2725<p><strong>SD (Low quality)</strong></p>
2726</td>
2727 <td class="tab0">
2728<p><strong>SD (High quality)</strong></p>
2729</td>
2730 <td class="tab0">
2731<p><strong>HD 720p1</strong></p>
2732</td>
2733 <td class="tab0">
2734<p><strong>HD 1080p1</strong></p>
2735</td>
2736 </tr>
2737 <tr>
2738 <td>
2739<p><strong>Video resolution</strong></p>
2740</td>
2741 <td>
2742<p>320 x 180 px</p>
2743</td>
2744 <td>
2745<p>640 x 360 px</p>
2746</td>
2747 <td>
2748<p>1280 x 720 px</p>
2749</td>
2750 <td>
2751<p>1920 x 1080 px</p>
2752</td>
2753 </tr>
2754 <tr>
2755 <td>
2756<p><strong>Video frame rate</strong></p>
2757</td>
2758 <td>
2759<p>30 fps</p>
2760</td>
2761 <td>
2762<p>30 fps</p>
2763</td>
2764 <td>
2765<p>30 fps / 60 fps2</p>
2766</td>
2767 <td>
2768<p>30 / 60 fps2</p>
2769</td>
2770 </tr>
2771 <tr>
2772 <td></td>
2773 <td></td>
2774 <td></td>
2775 <td></td>
2776 <td></td>
2777 </tr>
2778 <tr>
2779 <td>
2780<p><strong>Video bitrate</strong></p>
2781</td>
2782 <td>
2783<p>800 Kbps </p>
2784</td>
2785 <td>
2786<p>2 Mbps</p>
2787</td>
2788 <td>
2789<p>8 Mbps</p>
2790</td>
2791 <td>
2792<p>20 Mbps</p>
2793</td>
2794 </tr>
2795</table>
2796
2797
2798<p>1 Required for Android Television device implementations, but for other type of
2799devices only when supported by hardware.</p>
2800
2801<p>2 Required for Android Television device implementations.</p>
2802
2803<p>Android device implementations, when supporting VP9 codec as described in <a href="#heading=h.hitn8abpwkj2">section 5.1.3</a>, MUST support the following SD video decoding profiles and SHOULD support the
2804HD decoding profiles. Android Television devices are STRONGLY RECOMMENDED to
2805support the HD 1080p decoding profile and SHOULD support the UHD decoding
2806profile. When the UHD video decoding profile is supported, it MUST support 8
2807bit color depth.</p>
2808<table>
2809 <tr>
2810 <td class="tab0"></td>
2811 <td class="tab0">
2812<p><strong>SD (Low quality)</strong></p>
2813</td>
2814 <td class="tab0">
2815<p><strong>SD (High quality)</strong></p>
2816</td>
2817 <td class="tab0">
2818<p><strong>HD 720p 1</strong></p>
2819</td>
2820 <td class="tab0">
2821<p><strong>HD 1080p 2</strong></p>
2822</td>
2823 <td class="tab0">
2824<p><strong>UHD 2</strong></p>
2825</td>
2826 </tr>
2827 <tr>
2828 <td>
2829<p><strong>Video resolution</strong></p>
2830</td>
2831 <td>
2832<p>320 x 180 px</p>
2833</td>
2834 <td>
2835<p>640 x 360 px</p>
2836</td>
2837 <td>
2838<p>1280 x 720 px</p>
2839</td>
2840 <td>
2841<p>1920 x 1080 px</p>
2842</td>
2843 <td>
2844<p>3840 x 2160 px</p>
2845</td>
2846 </tr>
2847 <tr>
2848 <td>
2849<p><strong>Video frame rate</strong></p>
2850</td>
2851 <td>
2852<p>30 fps</p>
2853</td>
2854 <td>
2855<p>30 fps</p>
2856</td>
2857 <td>
2858<p>30 fps</p>
2859</td>
2860 <td>
2861<p>30 fps</p>
2862</td>
2863 <td>
2864<p>30 fps</p>
2865</td>
2866 </tr>
2867 <tr>
2868 <td>
2869<p><strong>Video bitrate</strong></p>
2870</td>
2871 <td>
2872<p>600 Kbps </p>
2873</td>
2874 <td>
2875<p>1.6 Mbps</p>
2876</td>
2877 <td>
2878<p>4 Mbps</p>
2879</td>
2880 <td>
2881<p>10 Mbps</p>
2882</td>
2883 <td>
2884<p>20 Mbps</p>
2885</td>
2886 </tr>
2887</table>
2888
2889
2890<p>1 Required for Android Television device implementations, but for other type of
2891devices only when supported by hardware.</p>
2892
2893<p>2 STRONGLY RECOMMENDED for Android Television device implementations when
2894supported by hardware.</p>
2895
2896<p>Android device implementations, when supporting H.265 codec as described in <a href="#heading=h.hitn8abpwkj2">section 5.1.3</a>, MUST support the Main Profile Level 3 Main tier and the following SD video
2897decoding profiles and SHOULD support the HD decoding profiles. Android
2898Television devices MUST support the Main Profile Level 4.1 Main tier and the HD
28991080p decoding profile and SHOULD support Main10 Level 5 Main Tier profile and
2900the UHD decoding profile.</p>
2901<table>
2902 <tr>
2903 <td class="tab0"></td>
2904 <td class="tab0">
2905<p><strong>SD (Low quality)</strong></p>
2906</td>
2907 <td class="tab0">
2908<p><strong>SD (High quality)</strong></p>
2909</td>
2910 <td class="tab0">
2911<p><strong>HD 720p </strong>1 </p>
2912</td>
2913 <td class="tab0">
2914<p><strong>HD 1080p </strong>1 </p>
2915</td>
2916 <td class="tab0">
2917<p><strong>UHD </strong>2</p>
2918</td>
2919 </tr>
2920 <tr>
2921 <td>
2922<p><strong>Video resolution</strong></p>
2923</td>
2924 <td>
2925<p>352 x 288 px</p>
2926</td>
2927 <td>
2928<p>640 x 360 px</p>
2929</td>
2930 <td>
2931<p>1280 x 720 px</p>
2932</td>
2933 <td>
2934<p>1920 x 1080 px</p>
2935</td>
2936 <td>
2937<p>3840 x 2160 px</p>
2938</td>
2939 </tr>
2940 <tr>
2941 <td>
2942<p><strong>Video frame rate</strong></p>
2943</td>
2944 <td>
2945<p>30 fps</p>
2946</td>
2947 <td>
2948<p>30 fps</p>
2949</td>
2950 <td>
2951<p>30 fps</p>
2952</td>
2953 <td>
2954<p>30 fps</p>
2955</td>
2956 <td>
2957<p>30 fps</p>
2958</td>
2959 </tr>
2960 <tr>
2961 <td>
2962<p><strong>Video bitrate</strong></p>
2963</td>
2964 <td>
2965<p>600 Kbps </p>
2966</td>
2967 <td>
2968<p>1.6 Mbps</p>
2969</td>
2970 <td>
2971<p>4 Mbps</p>
2972</td>
2973 <td>
2974<p>10 Mbps</p>
2975</td>
2976 <td>
2977<p>20 Mbps</p>
2978</td>
2979 </tr>
2980</table>
2981
2982
2983<p>1 Required for Android Television device implementation, but for other type of
2984devices only when supported by hardware.</p>
2985
2986<p>2 Required for Android Television device implementations when supported by
2987hardware.</p>
2988
2989<h2 id=5_4_audio_recording>5.4. Audio Recording</h2>
2990
2991
2992<p>While some of the requirements outlined in this section are stated as SHOULD
2993since Android 4.3, the Compatibility Definition for a future version is planned
2994to 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
2995compatibility when upgraded to the future version.</p>
2996
2997<h3 id=5_4_1_raw_audio_capture>5.4.1. Raw Audio Capture</h3>
2998
2999
3000<p>Device implementations that declare android.hardware.microphone MUST allow
3001capture of raw audio content with the following characteristics:</p>
3002
3003<ul>
3004 <li> <strong>Format</strong>: Linear PCM, 16-bit
3005 <li> <strong>Sampling rates</strong>: 8000, 11025, 16000, 44100
3006 <li> <strong>Channels</strong>: Mono
3007</ul>
3008
3009<p>Device implementations that declare android.hardware.microphone SHOULD allow
3010capture of raw audio content with the following characteristics:</p>
3011
3012<ul>
3013 <li> <strong>Format</strong>: Linear PCM, 16-bit
3014 <li> <strong>Sampling rates</strong>: 22050, 48000
3015 <li> <strong>Channels</strong>: Stereo
3016</ul>
3017
3018<h3 id=5_4_2_capture_for_voice_recognition>5.4.2. Capture for Voice Recognition</h3>
3019
3020
3021<p>In addition to the above recording specifications, when an application has
3022started recording an audio stream using the
3023android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source:</p>
3024
3025<ul>
3026 <li> The device SHOULD exhibit approximately flat amplitude versus frequency
3027characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
3028 <li> Audio input sensitivity SHOULD be set such that a 90 dB sound power level (SPL)
3029source at 1000 Hz yields RMS of 2500 for 16-bit samples.
3030 <li> PCM amplitude levels SHOULD linearly track input SPL changes over at least a 30
3031dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
3032 <li> Total harmonic distortion SHOULD be less than 1% for 1Khz at 90 dB SPL input
3033level at the microphone.
3034 <li> Noise reduction processing, if present, MUST be disabled.
3035 <li> Automatic gain control, if present, MUST be disabled
3036</ul>
3037
3038<p>If the platform supports noise suppression technologies tuned for speech
3039recognition, the effect MUST be controllable from the
3040android.media.audiofx.NoiseSuppressor API. Moreover, the UUID field for the
3041noise suppressor's effect descriptor MUST uniquely identify each implementation
3042of the noise suppression technology.</p>
3043
3044<h3 id=5_4_3_capture_for_rerouting_of_playback>5.4.3. Capture for Rerouting of Playback</h3>
3045
3046
3047<p>The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX
3048audio source. Devices that declare android.hardware.audio.output MUST properly
3049implement the REMOTE_SUBMIX audio source so that when an application uses the
3050android.media.AudioRecord API to record from this audio source, it can capture
3051a mix of all audio streams except for the following:</p>
3052
3053<ul>
3054 <li> STREAM_RING
3055 <li> STREAM_ALARM
3056 <li> STREAM_NOTIFICATION
3057</ul>
3058
3059<h2 id=5_5_audio_playback>5.5. Audio Playback</h2>
3060
3061
3062<p>Device implementations that declare android.hardware.audio.output MUST conform
3063to the requirements in this section.</p>
3064
3065<h3 id=5_5_1_raw_audio_playback>5.5.1. Raw Audio Playback</h3>
3066
3067
3068<p>The device MUST allow playback of raw audio content with the following
3069characteristics:</p>
3070
3071<ul>
3072 <li> <strong>Format</strong>: Linear PCM, 16-bit
3073 <li> <strong>Sampling rates</strong>: 8000, 11025, 16000, 22050, 32000, 44100
3074 <li> <strong>Channels</strong>: Mono, Stereo
3075</ul>
3076
3077<p>The device SHOULD allow playback of raw audio content with the following
3078characteristics:</p>
3079
3080<ul>
3081 <li> <strong>Sampling rates</strong>: 24000, 48000
3082</ul>
3083
3084<h3 id=5_5_2_audio_effects>5.5.2. Audio Effects</h3>
3085
3086
3087<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
3088android.hardware.audio.output:</p>
3089
3090<ul>
3091 <li> MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER
3092implementations controllable through the AudioEffect subclasses Equalizer,
3093LoudnessEnhancer
3094 <li> MUST support the visualizer API implementation, controllable through the
3095Visualizer class
3096 <li> SHOULD support the EFFECT_TYPE_BASS_BOOST, EFFECT_TYPE_ENV_REVERB,
3097EFFECT_TYPE_PRESET_REVERB, and EFFECT_TYPE_VIRTUALIZER implementations
3098controllable through the AudioEffect sub-classes BassBoost,
3099EnvironmentalReverb, PresetReverb, and Virtualizer
3100</ul>
3101
3102<h3 id=5_5_3_audio_output_volume>5.5.3. Audio Output Volume</h3>
3103
3104
3105<p>Android Television device implementations MUST include support for system
3106Master Volume and digital audio output volume attenuation on supported outputs,
3107except for compressed audio passthrough output (where no audio decoding is done
3108on the device).</p>
3109
3110<h2 id=5_6_audio_latency>5.6. Audio Latency</h2>
3111
3112
3113<p>Audio latency is the time delay as an audio signal passes through a system.
3114Many classes of applications rely on short latencies, to achieve real-time
3115sound effects.</p>
3116
3117<p>For the purposes of this section, use the following definitions:</p>
3118
3119<ul>
3120 <li> <strong>output latency</strong>—The interval between when an application writes a frame of PCM-coded data and
3121when the corresponding sound can be heard by an external listener or observed
3122by a transducer.
3123 <li> <strong>cold output latency</strong>—The output latency for the first frame, when the audio output system has been
3124idle and powered down prior to the request.
3125 <li> <strong>continuous output latency</strong>—The output latency for subsequent frames, after the device is playing audio.
3126 <li> <strong>input latency</strong>—The interval between when an external sound is presented to the device and
3127when an application reads the corresponding frame of PCM-coded data.
3128 <li> <strong>cold input latency</strong>—The sum of lost input time and the input latency for the first frame, when the
3129audio input system has been idle and powered down prior to the request.
3130 <li> <strong>continuous input latency</strong>—The input latency for subsequent frames, while the device is capturing audio.
3131 <li> <strong>cold output jitter</strong>—The variance among separate measurements of cold output latency values.
3132 <li> <strong>cold input jitter</strong>—The variance among separate measurements of cold input latency values.
3133 <li> <strong>continuous round-trip latency</strong>—The sum of continuous input latency plus continuous output latency plus 5
3134milliseconds.
3135 <li> <strong>OpenSL ES PCM buffer queue API</strong>—The set of PCM-related OpenSL ES APIs within Android NDK; see
3136NDK_root/docs/opensles/index.html.
3137</ul>
3138
3139<p>Device implementations that declare android.hardware.audio.output SHOULD meet
3140or exceed these audio output requirements:</p>
3141
3142<ul>
3143 <li> cold output latency of 100 milliseconds or less
3144 <li> continuous output latency of 45 milliseconds or less
3145 <li> minimize the cold output jitter
3146</ul>
3147
3148<p>If a device implementation meets the requirements of this section after any
3149initial calibration when using the OpenSL ES PCM buffer queue API, for
3150continuous output latency and cold output latency over at least one supported
3151audio output device, it MAY report support for low-latency audio, by reporting
3152the feature android.hardware.audio.low_latency via the
3153android.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
3154MUST NOT report support for low-latency audio.</p>
3155
3156<p>Device implementations that include android.hardware.microphone SHOULD meet
3157these input audio requirements:</p>
3158
3159<ul>
3160 <li> cold input latency of 100 milliseconds or less
3161 <li> continuous input latency of 30 milliseconds or less
3162 <li> continuous round-trip latency of 50 milliseconds or less
3163 <li> minimize the cold input jitter
3164</ul>
3165
3166<h2 id=5_7_network_protocols>5.7. Network Protocols</h2>
3167
3168
3169<p>Devices MUST support the media network protocols for audio and video playback
3170as 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>
3171
3172<ul>
3173 <li> RTSP (RTP, SDP)
3174 <li> HTTP(S) progressive streaming
3175 <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>]
3176</ul>
3177
3178<h2 id=5_8_secure_media>5.8. Secure Media</h2>
3179
3180
3181<p>Device implementations that support secure video output and are capable of
3182supporting secure surfaces MUST declare support for Display.FLAG_SECURE. Device
3183implementations that declare support for Display.FLAG_SECURE, if they support a
3184wireless display protocol, MUST secure the link with a cryptographically strong
3185mechanism such as HDCP 2.x or higher for Miracast wireless displays. Similarly
3186if they support a wired external display, the device implementations MUST
3187support HDCP 1.2 or higher. Android Television device implementations MUST
3188support HDCP 2.2 for devices supporting 4K resolution and HDCP 1.4 or above for
3189lower resolutions. The upstream Android open source implementation includes
3190support for wireless (Miracast) and wired (HDMI) displays that satisfies this
3191requirement.</p>
3192
3193<h1 id=6_developer_tools_and_options_compatibility>6. Developer Tools and Options Compatibility</h1>
3194
3195
3196<h2 id=6_1_developer_tools>6.1. Developer Tools</h2>
3197
3198
3199<p>Device implementations MUST support the Android Developer Tools provided in the
3200Android SDK. Android compatible devices MUST be compatible with:</p>
3201
3202<ul>
3203 <li> <strong>Android Debug Bridge (adb)</strong> [<a href="http://developer.android.com/tools/help/adb.html">Resources, 55</a>]
3204</ul>
3205
3206<p>Device implementations MUST support all adb functions as documented in the
3207Android SDK including dumpsys [<a href="https://source.android.com/devices/tech/input/dumpsys.html">Resources, 56</a>]. The device-side adb daemon MUST be inactive by default and there MUST be a
3208user-accessible mechanism to turn on the Android Debug Bridge. If a device
3209implementation omits USB peripheral mode, it MUST implement the Android Debug
3210Bridge via local-area network (such as Ethernet or 802.11). </p>
3211
3212<p>Android includes support for secure adb. Secure adb enables adb on known
3213authenticated hosts. Device implementations MUST support secure adb.</p>
3214
3215<ul>
3216 <li> <strong>Dalvik Debug Monitor Service (ddms)</strong> [<a href="http://developer.android.com/tools/debugging/ddms.html">Resources, 57</a>]
3217</ul>
3218
3219<p>Device implementations MUST support all ddms features as documented in the
3220Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default,
3221but MUST be supported whenever the user has activated the Android Debug Bridge,
3222as above.</p>
3223
3224<ul>
3225 <li> <strong>Monkey</strong> [<a href="http://developer.android.com/tools/help/monkey.html">Resources, 58</a>]
3226</ul>
3227
3228<p>Device implementations MUST include the Monkey framework, and make it available
3229for applications to use.</p>
3230
3231<ul>
3232 <li> <strong>SysTrace</strong> [<a href="http://developer.android.com/tools/help/systrace.html">Resources, 59</a>]
3233</ul>
3234
3235<p>Device implementations MUST support systrace tool as documented in the Android
3236SDK. Systrace must be inactive by default, and there MUST be a user-accessible
3237mechanism to turn on Systrace.</p>
3238
3239<p>Most Linux-based systems and Apple Macintosh systems recognize Android devices
3240using the standard Android SDK tools, without additional support; however
3241Microsoft Windows systems typically require a driver for new Android devices.
3242(For instance, new vendor IDs and sometimes new device IDs require custom USB
3243drivers for Windows systems.) If a device implementation is unrecognized by the
3244adb tool as provided in the standard Android SDK, device implementers MUST
3245provide Windows drivers allowing developers to connect to the device using the
3246adb protocol. These drivers MUST be provided for Windows XP, Windows Vista,
3247Windows 7, Windows 8, and Windows 9 in both 32-bit and 64-bit versions.</p>
3248
3249<h2 id=6_2_developer_options>6.2. Developer Options</h2>
3250
3251
3252<p>Android includes support for developers to configure application
3253development-related settings. Device implementations MUST honor the
3254android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application
3255development-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
3256default and enables users to launch Developer Options after pressing seven (7)
3257times on the <strong>Settings</strong> > <strong>About Device</strong> > <strong>Build Number</strong> menu item. Device implementations MUST provide a consistent experience for
3258Developer Options. Specifically, device implementations MUST hide Developer
3259Options by default and MUST provide a mechanism to enable Developer Options
3260that is consistent with the upstream Android implementation.</p>
3261
3262<h1 id=7_hardware_compatibility>7. Hardware Compatibility</h1>
3263
3264
3265<p>If a device includes a particular hardware component that has a corresponding
3266API for third-party developers, the device implementation MUST implement that
3267API as described in the Android SDK documentation. If an API in the SDK
3268interacts with a hardware component that is stated to be optional and the
3269device implementation does not possess that component:</p>
3270
3271<ul>
3272 <li> Complete class definitions (as documented by the SDK) for the component's APIs
3273MUST still be presented.
3274 <li> The API's behaviors MUST be implemented as no-ops in some reasonable fashion.
3275 <li> API methods MUST return null values where permitted by the SDK documentation.
3276 <li> API methods MUST return no-op implementations of classes where null values are
3277not permitted by the SDK documentation.
3278 <li> API methods MUST NOT throw exceptions not documented by the SDK documentation.
3279</ul>
3280
3281<p>A typical example of a scenario where these requirements apply is the telephony
3282API: even on non-phone devices, these APIs must be implemented as reasonable
3283no-ops.</p>
3284
3285<p>Device implementations MUST consistently report accurate hardware configuration
3286information via the getSystemAvailableFeatures() and hasSystemFeature(String)
3287methods on the android.content.pm.PackageManager class for the same build
3288fingerprint. [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a></p>
3289
3290<h2 id=7_1_display_and_graphics>7.1. Display and Graphics</h2>
3291
3292
3293<p>Android includes facilities that automatically adjust application assets and UI
3294layouts appropriately for the device, to ensure that third-party applications
3295run 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
3296this section.</p>
3297
3298<p>The units referenced by the requirements in this section are defined as
3299follows:</p>
3300
3301<ul>
3302 <li> <strong>physical diagonal size</strong>—The distance in inches between two opposing corners of the illuminated portion
3303of the display.
3304 <li> <strong>dots per inch (dpi)</strong>—The number of pixels encompassed by a linear horizontal or vertical span of
33051". Where dpi values are listed, both horizontal and vertical dpi must fall
3306within the range.
3307 <li> <strong>aspect ratio</strong>—The ratio of the longer dimension of the screen to the shorter dimension. For
3308example, a display of 480x854 pixels would be 854 / 480 = 1.779, or roughly
3309"16:9".
3310 <li> <strong>density-independent pixel (dp)</strong>—The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels =
3311dps * (density / 160).
3312</ul>
3313
3314<h3 id=7_1_1_screen_configuration>7.1.1. Screen Configuration</h3>
3315
3316
3317<h4 id=7_1_1_1_screen_size>7.1.1.1. Screen Size</h4>
3318
3319<table>
3320 <tr>
3321 <td class="tab2"></td>
3322 <td>
3323<p>Android Watch devices (detailed in <a href="#heading=h.40sdoojaw5k9">section 2</a>) MAY have smaller screen sizes as described in this section.</p>
3324</td>
3325 </tr>
3326</table>
3327
3328
3329<p>The Android UI framework supports a variety of different screen sizes, and
3330allows applications to query the device screen size (aka "screen layout") via
3331android.content.res.Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK.
3332Device implementations MUST report the correct screen size as defined in the
3333Android 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
3334implementations MUST report the correct screen size according to the following
3335logical density-independent pixel (dp) screen dimensions.</p>
3336
3337<ul>
3338 <li> Devices MUST have screen sizes of at least 426 dp x 320 dp ('small'), unless it
3339is an Android Watch device.
3340 <li> Devices that report screen size 'normal' MUST have screen sizes of at least 480
3341dp x 320 dp.
3342 <li> Devices that report screen size 'large' MUST have screen sizes of at least 640
3343dp x 480 dp.
3344 <li> Devices that report screen size 'xlarge' MUST have screen sizes of at least 960
3345dp x 720 dp.
3346</ul>
3347
3348<p>In addition, </p>
3349
3350<ul>
3351 <li> Android Watch devices MUST have a screen with the physical diagonal size in the
3352range from 1.1 to 2.5 inches
3353 <li> Other types of Android device implementations, with a physically integrated
3354screen, MUST have a screen at least 2.5 inches in physical diagonal size.
3355</ul>
3356
3357<p>Devices MUST NOT change their reported screen size at any time.</p>
3358
3359<p>Applications optionally indicate which screen sizes they support via the
3360<supports-screens> attribute in the AndroidManifest.xml file. Device
3361implementations MUST correctly honor applications' stated support for small,
3362normal, large, and xlarge screens, as described in the Android SDK
3363documentation.</p>
3364
3365<h4 id=7_1_1_2_screen_aspect_ratio>7.1.1.2. Screen Aspect Ratio</h4>
3366
3367<table>
3368 <tr>
3369 <td class="tab2"></td>
3370 <td>
3371<p>Android Watch devices MAY have an aspect ratio of 1.0 (1:1).</p>
3372</td>
3373 </tr>
3374</table>
3375
3376
3377<p>The screen aspect ratio MUST be a value from 1.3333 (4:3) to 1.86 (roughly
337816:9), but Android Watch devices MAY have an aspect ratio of 1.0 (1:1) because
3379such a device implementation will use a UI_MODE_TYPE_WATCH as the
3380android.content.res.Configuration.uiMode.</p>
3381
3382<h4 id=7_1_1_3_screen_density>7.1.1.3. Screen Density</h4>
3383
3384
3385<p>The Android UI framework defines a set of standard logical densities to help
3386application developers target application resources. Device implementations
3387MUST report only one of the following logical Android framework densities
3388through the android.util.DisplayMetrics APIs, and MUST execute applications at
3389this standard density and MUST NOT change the value at at any time for the
3390default display.</p>
3391
3392<ul>
3393 <li> 120 dpi (ldpi)
3394 <li> 160 dpi (mdpi)
3395 <li> 213 dpi (tvdpi)
3396 <li> 240 dpi (hdpi)
Unsuk Jungaa55a672015-04-01 08:30:23 -0700[diff] [blame^]3397 <li> 280 dpi (280dpi)
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]3398 <li> 320 dpi (xhdpi)
3399 <li> 400 dpi (400dpi)
3400 <li> 480 dpi (xxhdpi)
3401 <li> 560 dpi (560dpi)
3402 <li> 640 dpi (xxxhdpi)
3403</ul>
3404
3405<p>Device implementations SHOULD define the standard Android framework density
3406that is numerically closest to the physical density of the screen, unless that
3407logical density pushes the reported screen size below the minimum supported. If
3408the standard Android framework density that is numerically closest to the
3409physical density results in a screen size that is smaller than the smallest
3410supported compatible screen size (320 dp width), device implementations SHOULD
3411report the next lowest standard Android framework density.</p>
3412
3413<h3 id=7_1_2_display_metrics>7.1.2. Display Metrics</h3>
3414
3415
3416<p>Device implementations MUST report correct values for all display metrics
3417defined 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
3418external screen is used as the default display.</p>
3419
3420<h3 id=7_1_3_screen_orientation>7.1.3. Screen Orientation</h3>
3421
3422
3423<p>Devices MUST report which screen orientations they support
3424(android.hardware.screen.portrait and/or android.hardware.screen.landscape) and
3425MUST report at least one supported orientation. For example, a device with a
3426fixed orientation landscape screen, such as a television or laptop, SHOULD only
3427report android.hardware.screen.landscape.</p>
3428
3429<p>Devices that report both screen orientations MUST support dynamic orientation
3430by applications to either portrait or landscape screen orientation. That is,
3431the device must respect the application's request for a specific screen
3432orientation. Device implementations MAY select either portrait or landscape
3433orientation as the default.</p>
3434
3435<p>Devices MUST report the correct value for the device's current orientation,
3436whenever queried via the android.content.res.Configuration.orientation,
3437android.view.Display.getOrientation(), or other APIs.</p>
3438
3439<p>Devices MUST NOT change the reported screen size or density when changing
3440orientation.</p>
3441
3442<h3 id=7_1_4_2d_and_3d_graphics_acceleration>7.1.4. 2D and 3D Graphics Acceleration</h3>
3443
3444
3445<p>Device implementations MUST support both OpenGL ES 1.0 and 2.0, as embodied and
3446detailed in the Android SDK documentations. Device implementations SHOULD
3447support OpenGL ES 3.0 or 3.1 on devices capable of supporting it. Device
3448implementations MUST also support Android RenderScript, as detailed in the
3449Android SDK documentation [<a href="http://developer.android.com/guide/topics/renderscript/">Resources, 63</a>].</p>
3450
3451<p>Device implementations MUST also correctly identify themselves as supporting
3452OpenGL ES 1.0, OpenGL ES 2.0, OpenGL ES 3.0 or OpenGL 3.1. That is:</p>
3453
3454<ul>
3455 <li> The managed APIs (such as via the GLES10.getString()method MUST report support
3456for OpenGL ES 1.0 and OpenGL ES 2.0.
3457 <li> The native C/C++ OpenGL APIs (APIs available to apps via libGLES_v1CM.so,
3458libGLES_v2.so, or libEGL.so) MUST report support for OpenGL ES 1.0 and OpenGL
3459ES 2.0.
3460 <li> Device implementations that declare support for OpenGL ES 3.0 or 3.1 MUST
3461support the corresponding managed APIs and include support for native C/C++
3462APIs. On device implementations that declare support for OpenGL ES 3.0 or 3.1,
3463libGLESv2.so MUST export the corresponding function symbols in addition to the
3464OpenGL ES 2.0 function symbols.
3465</ul>
3466
3467<p>In addition to OpenGL ES 3.1, Android provides an extension pack with Java
3468interfaces [<a href="https://developer.android.com/reference/android/opengl/GLES31Ext.html">Resources, 64</a>] and native support for advanced graphics functionality such as tessellation
3469and the ASTC texture compression format. Android device implementations MAY
3470support this extension pack, and—only if fully implemented—MUST identify the
3471support through the android.hardware.opengles.aep feature flag.</p>
3472
3473<p>Also, device implementations MAY implement any desired OpenGL ES extensions.
3474However, device implementations MUST report via the OpenGL ES managed and
3475native APIs all extension strings that they do support, and conversely MUST NOT
3476report extension strings that they do not support.</p>
3477
3478<p>Note that Android includes support for applications to optionally specify that
3479they require specific OpenGL texture compression formats. These formats are
3480typically vendor-specific. Device implementations are not required by Android
3481to implement any specific texture compression format. However, they SHOULD
3482accurately report any texture compression formats that they do support, via the
3483getString() method in the OpenGL API.</p>
3484
3485<p>Android includes a mechanism for applications to declare that they want to
3486enable hardware acceleration for 2D graphics at the Application, Activity,
3487Window, or View level through the use of a manifest tag
3488android:hardwareAccelerated or direct API calls [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
3489
3490<p>Device implementations MUST enable hardware acceleration by default, and MUST
3491disable hardware acceleration if the developer so requests by setting
3492android:hardwareAccelerated="false" or disabling hardware acceleration directly
3493through the Android View APIs.</p>
3494
3495<p>In addition, device implementations MUST exhibit behavior consistent with the
3496Android SDK documentation on hardware acceleration [<a href="http://developer.android.com/guide/topics/graphics/hardware-accel.html">Resources, 65</a>].</p>
3497
3498<p>Android includes a TextureView object that lets developers directly integrate
3499hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
3500Device implementations MUST support the TextureView API, and MUST exhibit
3501consistent behavior with the upstream Android implementation.</p>
3502
3503<p>Android includes support for EGL_ANDROID_RECORDABLE, an EGLConfig attribute
3504that indicates whether the EGLConfig supports rendering to an ANativeWindow
3505that records images to a video. Device implementations MUST support
3506EGL_ANDROID_RECORDABLE extension [<a href="https://www.khronos.org/registry/egl/extensions/ANDROID/EGL_ANDROID_recordable.txt">Resources, 66</a>].</p>
3507
3508<h3 id=7_1_5_legacy_application_compatibility_mode>7.1.5. Legacy Application Compatibility Mode</h3>
3509
3510
3511<p>Android specifies a "compatibility mode" in which the framework operates in a
3512'normal' screen size equivalent (320dp width) mode for the benefit of legacy
3513applications not developed for old versions of Android that pre-date
3514screen-size independence. Device implementations MUST include support for
3515legacy application compatibility mode as implemented by the upstream Android
3516open source code. That is, device implementations MUST NOT alter the triggers
3517or thresholds at which compatibility mode is activated, and MUST NOT alter the
3518behavior of the compatibility mode itself.</p>
3519
3520<h3 id=7_1_6_screen_technology>7.1.6. Screen Technology</h3>
3521
3522
3523<p>The Android platform includes APIs that allow applications to render rich
3524graphics to the display. Devices MUST support all of these APIs as defined by
3525the Android SDK unless specifically allowed in this document. </p>
3526
3527<ul>
3528 <li> Devices MUST support displays capable of rendering 16-bit color graphics and
3529SHOULD support displays capable of 24-bit color graphics.
3530 <li> Devices MUST support displays capable of rendering animations.
3531 <li> The display technology used MUST have a pixel aspect ratio (PAR) between 0.9
3532and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~
353315% tolerance.
3534</ul>
3535
3536<h3 id=7_1_7_external_displays>7.1.7. External Displays</h3>
3537
3538
3539<p>Android includes support for secondary display to enable media sharing
3540capabilities and developer APIs for accessing external displays. If a device
3541supports an external display either via a wired, wireless, or an embedded
3542additional display connection then the device implementation MUST implement the
3543display 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>
3544
3545<h2 id=7_2_input_devices>7.2. Input Devices</h2>
3546
3547
3548<h3 id=7_2_1_keyboard>7.2.1. Keyboard</h3>
3549
3550<table>
3551 <tr>
3552 <td class="tab2"></td>
3553 <td>
3554<p>Android Watch devices MAY but other type of device implementations MUST
3555implement a soft keyboard.</p>
3556</td>
3557 </tr>
3558</table>
3559
3560
3561<p>Device implementations:</p>
3562
3563<ul>
3564 <li> MUST include support for the Input Management Framework (which allows
3565third-party developers to create Input Method Editors—i.e. soft keyboard) as
3566detailed at <a href="http://developer.android.com">http://developer.android.com</a>
3567 <li> MUST provide at least one soft keyboard implementation (regardless of whether a
3568hard keyboard is present) except for Android Watch devices where the screen
3569size makes it less reasonable to have a soft keyboard
3570 <li> MAY include additional soft keyboard implementations
3571 <li> MAY include a hardware keyboard
3572 <li> MUST NOT include a hardware keyboard that does not match one of the formats
3573specified 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)
3574</ul>
3575
3576<h3 id=7_2_2_non-touch_navigation>7.2.2. Non-touch Navigation</h3>
3577
3578<table>
3579 <tr>
3580 <td class="tab2"></td>
3581 <td>
3582<p>Android Television devices MUST support D-pad.</p>
3583</td>
3584 </tr>
3585</table>
3586
3587
3588<p>Device implementations:</p>
3589
3590<ul>
3591 <li> MAY omit a non-touch navigation option (trackball, d-pad, or wheel) if the
3592device implementation is not an Android Television device
3593 <li> MUST report the correct value for android.content.res.Configuration.navigation
3594[<a href="http://developer.android.com/reference/android/content/res/Configuration.html">Resources, 68</a>]
3595 <li> MUST provide a reasonable alternative user interface mechanism for the
3596selection and editing of text, compatible with Input Management Engines. The
3597upstream Android open source implementation includes a selection mechanism
3598suitable for use with devices that lack non-touch navigation inputs.
3599</ul>
3600
3601<h3 id=7_2_3_navigation_keys>7.2.3. Navigation Keys</h3>
3602
3603<table>
3604 <tr>
3605 <td class="tab2"></td>
3606 <td>
3607<p>The availability and visibility requirement of the Home, Recents, and Back
3608functions differ between device types as described in this section.</p>
3609</td>
3610 </tr>
3611</table>
3612
3613
3614<p>The Home, Recents, and Back functions (mapped to the key events KEYCODE_HOME,
3615KEYCODE_APP_SWITCH, KEYCODE_BACK, respectively) are essential to the Android
3616navigation paradigm and therefore;</p>
3617
3618<ul>
3619 <li> Android Handheld device implementations MUST provide the Home, Recents, and
3620Back functions.
3621 <li> Android Television device implementations MUST provide the Home and Back
3622functions.
3623 <li> Android Watch device implementations MUST have the Home function available to
3624the user, and the Back function except for when it is in UI_MODE_TYPE_WATCH.
3625 <li> All other types of device implementations MUST provide the Home and Back
3626functions.
3627</ul>
3628
3629<p>These functions MAY be implemented via dedicated physical buttons (such as
3630mechanical or capacitive touch buttons), or MAY be implemented using dedicated
3631software keys on a distinct portion of the screen, gestures, touch panel, etc.
3632Android supports both implementations. All of these functions MUST be
3633accessible with a single action (e.g. tap, double-click or gesture) when
3634visible.</p>
3635
3636<p>Recents function, if provided, MUST have a visible button or icon unless hidden
3637together with other navigation functions in full-screen mode. This does not
3638apply to devices upgrading from earlier Android versions that have physical
3639buttons for navigation and no recents key.</p>
3640
3641<p> The Home and Back functions, if provided, MUST each have a visible button or
3642icon unless hidden together with other navigation functions in full-screen mode
3643or when the uiMode UI_MODE_TYPE_MASK is set to UI_MODE_TYPE_WATCH.</p>
3644
3645<p>The Menu function is deprecated in favor of action bar since Android 4.0.
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]3646Therefore the new device implementations shipping with Android 5.0 and later MUST NOT
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]3647implement a dedicated physical button for the Menu function. Older device
3648implementations SHOULD NOT implement a dedicated physical button for the Menu
3649function, but if the physical Menu button is implemented and the device is
3650running applications with targetSdkVersion > 10, the device implementation:</p>
3651
3652<ul>
3653 <li> MUST display the action overflow button on the action bar when it is visible
3654and the resulting action overflow menu popup is not empty. For a device
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]3655implementation launched before Android 4.4 but upgrading to Android 5.1, this
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]3656is RECOMMENDED.
3657 <li> MUST NOT modify the position of the action overflow popup displayed by
3658selecting the overflow button in the action bar
3659 <li> MAY render the action overflow popup at a modified position on the screen when
3660it is displayed by selecting the physical menu button
3661</ul>
3662
3663<p>For backwards compatibility, device implementations MUST make the Menu function
3664available to applications when targetSdkVersion <= 10, either by a physical
3665button, a software key, or gestures. This Menu function should be presented
3666unless hidden together with other navigation functions.</p>
3667
3668<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
3669the Assist action available to the user at all times when running applications.
3670The Assist action SHOULD be implemented as a long-press on the Home button or a
3671swipe-up gesture on the software Home key. This function MAY be implemented via
3672another physical button, software key, or gesture, but MUST be accessible with
3673a single action (e.g. tap, double-click, or gesture) when other navigation keys
3674are visible.</p>
3675
3676<p>Device implementations MAY use a distinct portion of the screen to display the
3677navigation keys, but if so, MUST meet these requirements:</p>
3678
3679<ul>
3680 <li> Device implementation navigation keys MUST use a distinct portion of the
3681screen, not available to applications, and MUST NOT obscure or otherwise
3682interfere with the portion of the screen available to applications.
3683 <li> Device implementations MUST make available a portion of the display to
3684applications that meets the requirements defined in <a href="#heading=h.mrv5xyps1ba8">section 7.1.1</a>.
3685 <li> Device implementations MUST display the navigation keys when applications do
3686not specify a system UI mode, or specify SYSTEM_UI_FLAG_VISIBLE.
3687 <li> Device implementations MUST present the navigation keys in an unobtrusive "low
3688profile" (eg. dimmed) mode when applications specify
3689SYSTEM_UI_FLAG_LOW_PROFILE.
3690 <li> Device implementations MUST hide the navigation keys when applications specify
3691SYSTEM_UI_FLAG_HIDE_NAVIGATION.
3692</ul>
3693
3694<h3 id=7_2_4_touchscreen_input>7.2.4. Touchscreen Input</h3>
3695
3696<table>
3697 <tr>
3698 <td class="tab2"></td>
3699 <td>
3700<p>Android Handhelds and Watch Devices MUST support touchscreen input.</p>
3701</td>
3702 </tr>
3703</table>
3704
3705
3706<p>Device implementations SHOULD have a pointer input system of some kind (either
3707mouse-like or touch). However, if a device implementation does not support a
3708pointer input system, it MUST NOT report the android.hardware.touchscreen or
3709android.hardware.faketouch feature constant. Device implementations that do
3710include a pointer input system:</p>
3711
3712<ul>
3713 <li> SHOULD support fully independently tracked pointers, if the device input system
3714supports multiple pointers
3715 <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
3716</ul>
3717
3718<p>Android includes support for a variety of touchscreens, touch pads, and fake
3719touch input devices. Touchscreen based device implementations are associated
3720with 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
3721screen. Since the user is directly touching the screen, the system does not
3722require any additional affordances to indicate the objects being manipulated.
3723In contrast, a fake touch interface provides a user input system that
3724approximates a subset of touchscreen capabilities. For example, a mouse or
3725remote control that drives an on-screen cursor approximates touch, but requires
3726the user to first point or focus then click. Numerous input devices like the
3727mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]3728trackpad can support fake touch interactions. Android includes the feature
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]3729constant android.hardware.faketouch, which corresponds to a high-fidelity
3730non-touch (pointer-based) input device such as a mouse or trackpad that can
3731adequately emulate touch-based input (including basic gesture support), and
3732indicates that the device supports an emulated subset of touchscreen
3733functionality. Device implementations that declare the fake touch feature MUST
3734meet the fake touch requirements in <a href="#heading=h.7tz929qk2hjr">section 7.2.5</a>.</p>
3735
3736<p>Device implementations MUST report the correct feature corresponding to the
3737type of input used. Device implementations that include a touchscreen
3738(single-touch or better) MUST report the platform feature constant
3739android.hardware.touchscreen. Device implementations that report the platform
3740feature constant android.hardware.touchscreen MUST also report the platform
3741feature constant android.hardware.faketouch. Device implementations that do not
3742include a touchscreen (and rely on a pointer device only) MUST NOT report any
3743touchscreen feature, and MUST report only android.hardware.faketouch if they
3744meet the fake touch requirements in <a href="#heading=h.7tz929qk2hjr">section 7.2.5</a>.</p>
3745
3746<h3 id=7_2_5_fake_touch_input>7.2.5. Fake Touch Input</h3>
3747
3748
3749<p>Device implementations that declare support for android.hardware.faketouch:</p>
3750
3751<ul>
3752 <li> MUST report the absolute X and Y screen positions of the pointer location and
3753display a visual pointer on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]
3754 <li> MUST report touch event with the action code that specifies the state change
3755that 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>]
3756 <li> MUST support pointer down and up on an object on the screen, which allows users
3757to emulate tap on an object on the screen
3758 <li> MUST support pointer down, pointer up, pointer down then pointer up in the same
3759place on an object on the screen within a time threshold, which allows users to
3760emulate double tap on an object on the screen [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]
3761 <li> MUST support pointer down on an arbitrary point on the screen, pointer move to
3762any other arbitrary point on the screen, followed by a pointer up, which allows
3763users to emulate a touch drag
3764 <li> MUST support pointer down then allow users to quickly move the object to a
3765different position on the screen and then pointer up on the screen, which
3766allows users to fling an object on the screen
3767</ul>
3768
3769<p>Devices that declare support for android.hardware.faketouch.multitouch.distinct
3770MUST meet the requirements for faketouch above, and MUST also support distinct
3771tracking of two or more independent pointer inputs.</p>
3772
3773<h3 id=7_2_6_game_controller_support>7.2.6. Game Controller Support</h3>
3774
3775
3776<p>Android Television device implementations MUST support button mappings for game
3777controllers as listed below. The upstream Android implementation includes
3778implementation for game controllers that satisfies this requirement. </p>
3779
3780<h4 id=7_2_6_1_button_mappings>7.2.6.1. Button Mappings</h4>
3781
3782
3783<p>Android Television device implementations MUST support the following key
3784mappings:</p>
3785<table>
3786 <tr>
3787 <td class="tab0">
3788<p><strong>Button</strong></p>
3789</td>
3790 <td class="tab0">
3791<p><strong>HID Usage</strong>2</p>
3792</td>
3793 <td class="tab0">
3794<p><strong>Android Button</strong></p>
3795</td>
3796 </tr>
3797 <tr>
3798 <td>
3799<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_A">A</a>1</p>
3800</td>
3801 <td>
3802<p>0x09 0x0001</p>
3803</td>
3804 <td>
3805<p>KEYCODE_BUTTON_A (96)</p>
3806</td>
3807 </tr>
3808 <tr>
3809 <td>
3810<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_B">B</a>1</p>
3811</td>
3812 <td>
3813<p>0x09 0x0002</p>
3814</td>
3815 <td>
3816<p>KEYCODE_BUTTON_B (97)</p>
3817</td>
3818 </tr>
3819 <tr>
3820 <td>
3821<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_X">X</a>1</p>
3822</td>
3823 <td>
3824<p>0x09 0x0004</p>
3825</td>
3826 <td>
3827<p>KEYCODE_BUTTON_X (99)</p>
3828</td>
3829 </tr>
3830 <tr>
3831 <td>
3832<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_Y">Y</a>1</p>
3833</td>
3834 <td>
3835<p>0x09 0x0005</p>
3836</td>
3837 <td>
3838<p>KEYCODE_BUTTON_Y (100)</p>
3839</td>
3840 </tr>
3841 <tr>
3842 <td>
3843<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_UP">D-pad up</a>1</p>
3844
3845<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_DOWN">D-pad down</a>1</p>
3846</td>
3847 <td>
3848<p>0x01 0x00393</p>
3849</td>
3850 <td>
3851<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_Y">AXIS_HAT_Y</a>4</p>
3852</td>
3853 </tr>
3854 <tr>
3855 <td>
3856<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_LEFT">D-pad left</a>1</p>
3857
3858<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_DPAD_RIGHT">D-pad right</a>1</p>
3859</td>
3860 <td>
3861<p>0x01 0x00393</p>
3862</td>
3863 <td>
3864<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_HAT_X">AXIS_HAT_X4 </a></p>
3865</td>
3866 </tr>
3867 <tr>
3868 <td>
3869<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_L1">Left shoulder button</a>1</p>
3870</td>
3871 <td>
3872<p>0x09 0x0007</p>
3873</td>
3874 <td>
3875<p>KEYCODE_BUTTON_L1 (102)</p>
3876</td>
3877 </tr>
3878 <tr>
3879 <td>
3880<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_R1">Right shoulder button</a>1</p>
3881</td>
3882 <td>
3883<p>0x09 0x0008</p>
3884</td>
3885 <td>
3886<p>KEYCODE_BUTTON_R1 (103)</p>
3887</td>
3888 </tr>
3889 <tr>
3890 <td>
3891<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBL">Left stick click</a>1</p>
3892</td>
3893 <td>
3894<p>0x09 0x000E</p>
3895</td>
3896 <td>
3897<p>KEYCODE_BUTTON_THUMBL (106)</p>
3898</td>
3899 </tr>
3900 <tr>
3901 <td>
3902<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BUTTON_THUMBR">Right stick click</a>1</p>
3903</td>
3904 <td>
3905<p>0x09 0x000F</p>
3906</td>
3907 <td>
3908<p>KEYCODE_BUTTON_THUMBR (107)</p>
3909</td>
3910 </tr>
3911 <tr>
3912 <td>
3913<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME">Home</a>1</p>
3914</td>
3915 <td>
3916<p>0x0c 0x0223</p>
3917</td>
3918 <td>
3919<p>KEYCODE_HOME (3)</p>
3920</td>
3921 </tr>
3922 <tr>
3923 <td>
3924<p><a href="http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_BACK">Back</a>1</p>
3925</td>
3926 <td>
3927<p>0x0c 0x0224</p>
3928</td>
3929 <td>
3930<p>KEYCODE_BACK (4)</p>
3931</td>
3932 </tr>
3933</table>
3934
3935
3936<p>1 [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>]</p>
3937
3938<p>2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).</p>
3939
3940<p>3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a
3941Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a
3942Report Size of 4. The logical value is defined to be the clockwise rotation
3943away from the vertical axis; for example, a logical value of 0 represents no
3944rotation and the up button being pressed, while a logical value of 1 represents
3945a rotation of 45 degrees and both the up and left keys being pressed.</p>
3946
3947<p>4 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
3948<table>
3949 <tr>
3950 <td class="tab0">
3951<p><strong>Analog Controls</strong>1</p>
3952</td>
3953 <td class="tab0">
3954<p><strong>HID Usage</strong></p>
3955</td>
3956 <td class="tab0">
3957<p><strong>Android Button</strong></p>
3958</td>
3959 </tr>
3960 <tr>
3961 <td>
3962<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_LTRIGGER">Left Trigger</a></p>
3963</td>
3964 <td>
3965<p>0x02 0x00C5</p>
3966</td>
3967 <td>
3968<p>AXIS_LTRIGGER </p>
3969</td>
3970 </tr>
3971 <tr>
3972 <td>
3973<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_THROTTLE">Right Trigger</a></p>
3974</td>
3975 <td>
3976<p>0x02 0x00C4</p>
3977</td>
3978 <td>
3979<p>AXIS_RTRIGGER </p>
3980</td>
3981 </tr>
3982 <tr>
3983 <td>
3984<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Y">Left Joystick</a></p>
3985</td>
3986 <td>
3987<p>0x01 0x0030</p>
3988
3989<p>0x01 0x0031</p>
3990</td>
3991 <td>
3992<p>AXIS_X</p>
3993
3994<p>AXIS_Y</p>
3995</td>
3996 </tr>
3997 <tr>
3998 <td>
3999<p><a href="http://developer.android.com/reference/android/view/MotionEvent.html#AXIS_Z">Right Joystick</a></p>
4000</td>
4001 <td>
4002<p>0x01 0x0032</p>
4003
4004<p>0x01 0x0035</p>
4005</td>
4006 <td>
4007<p>AXIS_Z</p>
4008
4009<p>AXIS_RZ</p>
4010</td>
4011 </tr>
4012</table>
4013
4014
4015<p>1 [<a href="http://developer.android.com/reference/android/view/MotionEvent.html">Resources, 71</a>]</p>
4016
4017<h3 id=7_2_7_remote_control>7.2.7. Remote Control</h3>
4018
4019
4020<p>Android Television device implementations SHOULD provide a remote control to
4021allow users to access the TV interface. The remote control MAY be a physical
4022remote or can be a software-based remote that is accessible from a mobile phone
4023or tablet. The remote control MUST meet the requirements defined below.</p>
4024
4025<ul>
4026 <li> <strong>Search affordance</strong>—Device implementations MUST fire KEYCODE_SEARCH when the user invokes voice
4027search either on the physical or software-based remote.
4028 <li> <strong>Navigation</strong>—All Android Television remotes MUST include Back, Home, and Select buttons and
4029support for D-pad events [<a href="http://developer.android.com/reference/android/view/KeyEvent.html">Resources, 72</a>].
4030</ul>
4031
4032<h2 id=7_3_sensors>7.3. Sensors</h2>
4033
4034
4035<p>Android includes APIs for accessing a variety of sensor types. Devices
4036implementations generally MAY omit these sensors, as provided for in the
4037following subsections. If a device includes a particular sensor type that has a
4038corresponding API for third-party developers, the device implementation MUST
4039implement that API as described in the Android SDK documentation and the
4040Android Open Source documentation on sensors [<a href="http://source.android.com/devices/sensors">Resources, 73</a>]. For example, device implementations:</p>
4041
4042<ul>
4043 <li> MUST accurately report the presence or absence of sensors per the
4044android.content.pm.PackageManager class [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53]</a>
4045 <li> MUST return an accurate list of supported sensors via the
4046SensorManager.getSensorList() and similar methods
4047 <li> MUST behave reasonably for all other sensor APIs (for example, by returning
4048true or false as appropriate when applications attempt to register listeners,
4049not calling sensor listeners when the corresponding sensors are not present;
4050etc.)
4051 <li> MUST report all sensor measurements using the relevant International System of
4052Units (metric) values for each sensor type as defined in the Android SDK
4053documentation [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>]
4054 <li> SHOULD report the event time in nanoseconds as defined in the Android SDK
4055documentation, representing the time the event happened and synchronized with
4056the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices
4057are <strong>very strongly encouraged</strong> to meet these requirement so they will be able to upgrade to the future
4058platform releases where this might become a REQUIRED component. The
4059synchronization error SHOULD be below 100 milliseconds [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html#timestamp">Resources, 75</a>].
4060</ul>
4061
4062<p>The list above is not comprehensive; the documented behavior of the Android SDK
4063and the Android Open Source Documentations on Sensors [<a href="http://source.android.com/devices/sensors">Resources, 73</a>] is to be considered authoritative.</p>
4064
4065<p>Some sensor types are composite, meaning they can be derived from data provided
4066by one or more other sensors. (Examples include the orientation sensor, and the
4067linear acceleration sensor.) Device implementations SHOULD implement these
4068sensor types, when they include the prerequisite physical sensors as described
4069in [<a href="http://source.android.com/devices/sensors/composite_sensors.html">Resources, 76</a>]. If a device implementation includes a composite sensor it MUST implement the
4070sensor as described in the Android Open Source documentation on composite
4071sensors [<a href="http://source.android.com/devices/sensors/composite_sensors.html">Resources, 76</a>].</p>
4072
4073<p>Some Android sensor supports a "continuous" trigger mode, which returns data
4074continuously [<a href="http://source.android.com/devices/sensors/base_triggers.html#continuous">Resources, 77</a>]. For any API indicated by the Android SDK documentation to be a continuous
4075sensor, device implementations MUST continuously provide periodic data samples
4076that SHOULD have a jitter below 3%, where jitter is defined as the standard
4077deviation of the difference of the reported timestamp values between
4078consecutive events.</p>
4079
4080<p>Note that the device implementations MUST ensure that the sensor event stream
4081MUST NOT prevent the device CPU from entering a suspend state or waking up from
4082a suspend state.</p>
4083
4084<p>Finally, when several sensors are activated, the power consumption SHOULD NOT
4085exceed the sum of the individual sensor’s reported power consumption.</p>
4086
4087<h3 id=7_3_1_accelerometer>7.3.1. Accelerometer</h3>
4088
4089
4090<p>Device implementations SHOULD include a 3-axis accelerometer. Android Handheld
4091devices and Android Watch devices are strongly encouraged to include this
4092sensor. If a device implementation does include a 3-axis accelerometer, it:</p>
4093
4094<ul>
4095 <li> MUST implement and report TYPE_ACCELEROMETER sensor [<a href="http://developer.android.com/reference/android/hardware/Sensor.html#TYPE_ACCELEROMETER">Resources, 78</a>]
4096 <li> MUST be able to report events up to a frequency of at least 100 Hz and SHOULD
4097report events up to at least 200 Hz
4098 <li> MUST comply with the Android sensor coordinate system as detailed in the
4099Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>]
4100 <li> MUST be capable of measuring from freefall up to four times the gravity (4g) or
4101more on any axis
4102 <li> MUST have a resolution of at least 8-bits and SHOULD have a resolution of at
4103least 16-bits
4104 <li> SHOULD be calibrated while in use if the characteristics changes over the life
4105cycle and compensated, and preserve the compensation parameters between device
4106reboots
4107 <li> SHOULD be temperature compensated
4108 <li> MUST have a standard deviation no greater than 0.05 m/s^, where the standard
4109deviation should be calculated on a per axis basis on samples collected over a
4110period of at least 3 seconds at the fastest sampling rate
4111 <li> SHOULD implement the TYPE_SIGNIFICANT_MOTION, TYPE_TILT_DETECTOR,
4112TYPE_STEP_DETECTOR, TYPE_STEP_COUNTER composite sensors as described in the
4113Android 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
4114sensors are implemented, the sum of their power consumption MUST always be less
4115than 4 mW and SHOULD each be below 2 mW and 0.5 mW for when the device is in a
4116dynamic or static condition.
4117 <li> If a gyroscope sensor is included, MUST implement the TYPE_GRAVITY and
4118TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
4119TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
4120are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.
4121 <li> SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if a gyroscope sensor
4122and a magnetometer sensor is also included
4123</ul>
4124
4125<h3 id=7_3_2_magnetometer>7.3.2. Magnetometer</h3>
4126
4127
4128<p>Device implementations SHOULD include a 3-axis magnetometer (compass). If a
4129device does include a 3-axis magnetometer, it:</p>
4130
4131<ul>
4132 <li> MUST implement the TYPE_MAGNETIC_FIELD sensor and SHOULD also implement
4133TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor. Existing and new Android devices are
4134strongly encouraged to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.
4135 <li> MUST be able to report events up to a frequency of at least 10 Hz and SHOULD
4136report events up to at least 50 Hz
4137 <li> MUST comply with the Android sensor coordinate system as detailed in the
4138Android APIs [<a href="http://developer.android.com/reference/android/hardware/SensorEvent.html">Resources, 74</a>]
4139 <li> MUST be capable of measuring between -900 μT and +900 μT on each axis before
4140saturating
4141 <li> MUST have a hard iron offset value less than 700 μT and SHOULD have a value
4142below 200 μT, by placing the magnetometer far from dynamic (current-induced)
4143and static (magnet-induced) magnetic fields
4144 <li> MUST have a resolution equal or denser than 0.6 μT and SHOULD have a resolution
4145equal or denser than 0.2 μT
4146 <li> SHOULD be temperature compensated
4147 <li> MUST support online calibration and compensation of the hard iron bias, and
4148preserve the compensation parameters between device reboots
4149 <li> MUST have the soft iron compensation applied—the calibration can be done either
4150while in use or during the production of the device
4151 <li> SHOULD have a standard deviation, calculated on a per axis basis on samples
4152collected over a period of at least 3 seconds at the fastest sampling rate, no
4153greater than 0.5 μT
4154 <li> SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
4155sensor and a gyroscope sensor is also included
4156 <li> MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor if an accelerometer
4157sensor is also implemented. However if implemented, it MUST consume less than
415810 mW and SHOULD consume less than 3 mW when the sensor is registered for batch
4159mode at 10 Hz.
4160</ul>
4161
4162<h3 id=7_3_3_gps>7.3.3. GPS</h3>
4163
4164
4165<p>Device implementations SHOULD include a GPS receiver. If a device
4166implementation does include a GPS receiver, it SHOULD include some form of
4167"assisted GPS" technique to minimize GPS lock-on time.</p>
4168
4169<h3 id=7_3_4_gyroscope>7.3.4. Gyroscope</h3>
4170
4171
4172<p>Device implementations SHOULD include a gyroscope (angular change sensor).
4173Devices SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is
4174also included. If a device implementation includes a gyroscope, it:</p>
4175
4176<ul>
4177 <li> MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement
4178TYPE_GYROSCOPE_UNCALIBRATED sensor. Existing and new Android devices are
4179strongly encouraged to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.
4180 <li> MUST be capable of measuring orientation changes up to 1,000 degrees per second
4181 <li> MUST be able to report events up to a frequency of at least 100 Hz and SHOULD
4182report events up to at least 200 Hz
4183 <li> MUST have a resolution of 12-bits or more and SHOULD have a resolution of
418416-bits or more
4185 <li> MUST be temperature compensated
4186 <li> MUST be calibrated and compensated while in use, and preserve the compensation
4187parameters between device reboots
4188 <li> MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz,
4189or rad^2 / s). The variance is allowed to vary with the sampling rate, but must
4190be constrained by this value. In other words, if you measure the variance of
4191the gyro at 1 Hz sampling rate it should be no greater than 1e-7 rad^2/s^2.
4192 <li> SHOULD implement a TYPE_ROTATION_VECTOR composite sensor, if an accelerometer
4193sensor and a magnetometer sensor is also included
4194 <li> If an accelerometer sensor is included, MUST implement the TYPE_GRAVITY and
4195TYPE_LINEAR_ACCELERATION composite sensors and SHOULD implement the
4196TYPE_GAME_ROTATION_VECTOR composite sensor. Existing and new Android devices
4197are strongly encouraged to implement the TYPE_GAME_ROTATION_VECTOR sensor.
4198</ul>
4199
4200<h3 id=7_3_5_barometer>7.3.5. Barometer</h3>
4201
4202
4203<p>Device implementations SHOULD include a barometer (ambient air pressure
4204sensor). If a device implementation includes a barometer, it:</p>
4205
4206<ul>
4207 <li> MUST implement and report TYPE_PRESSURE sensor
4208 <li> MUST be able to deliver events at 5 Hz or greater
4209 <li> MUST have adequate precision to enable estimating altitude
4210 <li> MUST be temperature compensated
4211</ul>
4212
4213<h3 id=7_3_6_thermometer>7.3.6. Thermometer</h3>
4214
4215
4216<p>Device implementations MAY include an ambient thermometer (temperature sensor).
4217If present, it MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and it MUST
4218measure the ambient (room) temperature in degrees Celsius.</p>
4219
4220<p>Device implementations MAY but SHOULD NOT include a CPU temperature sensor. If
4221present, it MUST be defined as SENSOR_TYPE_TEMPERATURE, it MUST measure the
4222temperature of the device CPU, and it MUST NOT measure any other temperature.
4223Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.</p>
4224
4225<h3 id=7_3_7_photometer>7.3.7. Photometer</h3>
4226
4227
4228<p>Device implementations MAY include a photometer (ambient light sensor).</p>
4229
4230<h3 id=7_3_8_proximity_sensor>7.3.8. Proximity Sensor</h3>
4231
4232
4233<p>Device implementations MAY include a proximity sensor. Devices that can make a
4234voice call and indicate any value other than PHONE_TYPE_NONE in getPhoneType
4235SHOULD include a proximity sensor. If a device implementation does include a
4236proximity sensor, it:</p>
4237
4238<ul>
4239 <li> MUST measure the proximity of an object in the same direction as the screen.
4240That is, the proximity sensor MUST be oriented to detect objects close to the
4241screen, as the primary intent of this sensor type is to detect a phone in use
4242by the user. If a device implementation includes a proximity sensor with any
4243other orientation, it MUST NOT be accessible through this API.
4244 <li> MUST have 1-bit of accuracy or more
4245</ul>
4246
4247<h2 id=7_4_data_connectivity>7.4. Data Connectivity</h2>
4248
4249
4250<h3 id=7_4_1_telephony>7.4.1. Telephony</h3>
4251
4252
4253<p>"Telephony" as used by the Android APIs and this document refers specifically
4254to hardware related to placing voice calls and sending SMS messages via a GSM
4255or CDMA network. While these voice calls may or may not be packet-switched,
4256they are for the purposes of Android considered independent of any data
4257connectivity that may be implemented using the same network. In other words,
4258the Android "telephony" functionality and APIs refer specifically to voice
4259calls and SMS. For instance, device implementations that cannot place calls or
4260send/receive SMS messages MUST NOT report the android.hardware.telephony
4261feature or any subfeatures, regardless of whether they use a cellular network
4262for data connectivity.</p>
4263
4264<p>Android MAY be used on devices that do not include telephony hardware. That is,
4265Android is compatible with devices that are not phones. However, if a device
4266implementation does include GSM or CDMA telephony, it MUST implement full
4267support for the API for that technology. Device implementations that do not
4268include telephony hardware MUST implement the full APIs as no-ops.</p>
4269
4270<h3 id=7_4_2_ieee_802_11_wi-fi>7.4.2. IEEE 802.11 (Wi-Fi)</h3>
4271
4272<table>
4273 <tr>
4274 <td class="tab2"></td>
4275 <td>
4276<p>Android Television device implementations MUST include Wi-Fi support. </p>
4277</td>
4278 </tr>
4279</table>
4280
4281
4282<p>Android Television device implementations MUST include support for one or more
4283forms of 802.11 (b/g/a/n, etc.) and other types of Android device
4284implementation SHOULD include support for one or more forms of 802.11. If a
4285device implementation does include support for 802.11 and exposes the
4286functionality to a third-party application, it MUST implement the corresponding
4287Android API and:</p>
4288
4289<ul>
4290 <li> MUST report the hardware feature flag android.hardware.wifi
4291 <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>]
4292 <li> MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets
4293(224.0.0.251) at any time of operation including when the screen is not in an
4294active state
4295</ul>
4296
4297<h4 id=7_4_2_1_wi-fi_direct>7.4.2.1. Wi-Fi Direct</h4>
4298
4299
4300<p>Device implementations SHOULD include support for Wi-Fi Direct (Wi-Fi
4301peer-to-peer). If a device implementation does include support for Wi-Fi
4302Direct, it MUST implement the corresponding Android API as described in the SDK
4303documentation [<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>
4304
4305<ul>
4306 <li> MUST report the hardware feature android.hardware.wifi.direct
4307 <li> MUST support regular Wi-Fi operation
4308 <li> SHOULD support concurrent Wi-Fi and Wi-Fi Direct operation
4309</ul>
4310
4311<h4 id=7_4_2_2_wi-fi_tunneled_direct_link_setup>7.4.2.2. Wi-Fi Tunneled Direct Link Setup</h4>
4312
4313<table>
4314 <tr>
4315 <td class="tab2"></td>
4316 <td>
4317<p>Android Television device implementations MUST include support for Wi-Fi
4318Tunneled Direct Link Setup (TDLS).</p>
4319</td>
4320 </tr>
4321</table>
4322
4323
4324<p>Android Television device implementations MUST include support for Wi-Fi
4325Tunneled Direct Link Setup (TDLS) and other types of Android device
4326implementations SHOULD include support for Wi-Fi TDLS as described in the
4327Android 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
4328by the WiFiManager API, the device:</p>
4329
4330<ul>
4331 <li> SHOULD use TDLS only when it is possible AND beneficial
4332 <li> SHOULD have some heuristic and NOT use TDLS when its performance might be worse
4333than going through the Wi-Fi access point
4334</ul>
4335
4336<h3 id=7_4_3_bluetooth>7.4.3. Bluetooth</h3>
4337
4338<table>
4339 <tr>
4340 <td class="tab2"></td>
4341 <td>
4342<p>Android Television device implementations MUST support Bluetooth and Bluetooth
4343LE and Android Watch device implementations MUST support Bluetooth.</p>
4344</td>
4345 </tr>
4346</table>
4347
4348
4349<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
4350Energy MUST declare the relevant platform features (android.hardware.bluetooth
4351and android.hardware.bluetooth_le respectively) and implement the platform
4352APIs. Device implementations SHOULD implement relevant Bluetooth profiles such
4353as A2DP, AVCP, OBEX, etc. as appropriate for the device. Android Television
4354device implementations MUST support Bluetooth and Bluetooth LE. </p>
4355
4356<p>Device implementations including support for Bluetooth Low Energy:</p>
4357
4358<ul>
4359 <li> MUST declare the hardware feature android.hardware.bluetooth_le
4360 <li> MUST enable the GATT (generic attribute profile) based Bluetooth APIs as
4361described in the SDK documentation and [<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">Resources, 82</a>]
4362 <li> SHOULD support offloading of the filtering logic to the bluetooth chipset when
4363implementing 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
4364implemented whenever queried via the
4365android.bluetooth.BluetoothAdapter.isOffloadedFilteringSupported() method
4366 <li> SHOULD support offloading of the batched scanning to the bluetooth chipset, but
4367if not supported, MUST report ‘false’ whenever queried via the
4368android.bluetooth.BluetoothAdapater.isOffloadedScanBatchingSupported() method.
4369 <li> SHOULD support multi advertisement with at least 4 slots, but if not supported,
4370MUST report ‘false’ whenever queried via the
4371android.bluetooth.BluetoothAdapter.isMultipleAdvertisementSupported() method
4372</ul>
4373
4374<h3 id=7_4_4_near-field_communications>7.4.4. Near-Field Communications</h3>
4375
4376
4377<p>Device implementations SHOULD include a transceiver and related hardware for
4378Near-Field Communications (NFC). If a device implementation does include NFC
4379hardware and plans to make it available to third-party apps, then it:</p>
4380
4381<ul>
4382 <li> MUST report the android.hardware.nfc feature from the
4383android.content.pm.PackageManager.hasSystemFeature() method [<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">Resources, 53</a>]
4384 <li> MUST be capable of reading and writing NDEF messages via the following NFC
4385standards:
4386 <ul>
4387 <li> MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC
4388Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the
4389following NFC standards:
4390 <ul>
4391 <li> NfcA (ISO14443-3A)
4392 <li> NfcB (ISO14443-3B)
4393 <li> NfcF (JIS 6319-4)
4394 <li> IsoDep (ISO 14443-4)
4395 <li> NFC Forum Tag Types 1, 2, 3, 4 (defined by the NFC Forum)
4396 </ul>
4397 <li> SHOULD be capable of reading and writing NDEF messages via the following NFC
4398standards. Note that while the NFC standards below are stated as SHOULD, the
4399Compatibility Definition for a future version is planned to change these to
4400MUST. These standards are optional in this version but will be required in
4401future versions. Existing and new devices that run this version of Android are <strong>very strongly encouraged</strong> to meet these requirements now so they will be able to upgrade to the future
4402platform releases.
4403 <ul>
4404 <li> NfcV (ISO 15693)
4405 </ul>
4406 <li> MUST be capable of transmitting and receiving data via the following
4407peer-to-peer standards and protocols:
4408 <ul>
4409 <li> ISO 18092
4410 <li> LLCP 1.0 (defined by the NFC Forum)
4411 <li> SDP 1.0 (defined by the NFC Forum)
4412 <li> NDEF Push Protocol [<a href="http://static.googleusercontent.com/media/source.android.com/en/us/compatibility/ndef-push-protocol.pdf">Resources, 84</a>]
4413 <li> SNEP 1.0 (defined by the NFC Forum)
4414 </ul>
4415 <li> MUST include support for Android Beam [<a href="http://developer.android.com/guide/topics/connectivity/nfc/nfc.html">Resources, 85</a>]:
4416 <ul>
4417 <li> MUST implement the SNEP default server. Valid NDEF messages received by the
4418default SNEP server MUST be dispatched to applications using the
4419android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings
4420MUST NOT disable dispatch of incoming NDEF message.
4421 <li> MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing
4422settings [<a href="http://developer.android.com/reference/android/provider/Settings.html#ACTION_NFCSHARING_SETTINGS">Resources, 86</a>]
4423 <li> MUST implement the NPP server. Messages received by the NPP server MUST be
4424processed the same way as the SNEP default server.
4425 <li> MUST implement a SNEP client and attempt to send outbound P2P NDEF to the
4426default SNEP server when Android Beam is enabled. If no default SNEP server is
4427found then the client MUST attempt to send to an NPP server.
4428 <li> MUST allow foreground activities to set the outbound P2P NDEF message using
4429android.nfc.NfcAdapter.setNdefPushMessage, and
4430android.nfc.NfcAdapter.setNdefPushMessageCallback, and
4431android.nfc.NfcAdapter.enableForegroundNdefPush
4432 <li> SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before
4433sending outbound P2P NDEF messages
4434 <li> SHOULD enable Android Beam by default and MUST be able to send and receive
4435using Android Beam, even when another proprietary NFC P2p mode is turned on
4436 <li> MUST support NFC Connection handover to Bluetooth when the device supports
4437Bluetooth Object Push Profile. Device implementations MUST support connection
4438handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris, by
4439implementing the "Connection Handover version 1.2" [<a href="http://www.nfc-forum.org/specs/spec_list/#conn_handover">Resources, 87</a>] and "Bluetooth Secure Simple Pairing Using NFC version 1.0" [<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
4440LLCP service with service name "urn:nfc:sn:handover" for exchanging the
4441handover request/select records over NFC, and it MUST use the Bluetooth Object
4442Push Profile for the actual Bluetooth data transfer. For legacy reasons (to
4443remain compatible with Android 4.1 devices), the implementation SHOULD still
4444accept SNEP GET requests for exchanging the handover request/select records
4445over NFC. However an implementation itself SHOULD NOT send SNEP GET requests
4446for performing connection handover.
4447 </ul>
4448 <li> MUST poll for all supported technologies while in NFC discovery mode
4449 <li> SHOULD be in NFC discovery mode while the device is awake with the screen
4450active and the lock-screen unlocked
4451</ul>
4452</ul>
4453
4454<p>(Note that publicly available links are not available for the JIS, ISO, and NFC
4455Forum specifications cited above.)</p>
4456
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]4457<p>Android includes support for NFC Host Card Emulation (HCE) mode. If a
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]4458device implementation does include an NFC controller capable of HCE and
4459Application ID (AID) routing, then it:</p>
4460
4461<ul>
4462 <li> MUST report the android.hardware.nfc.hce feature constant
4463 <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>]
4464</ul>
4465
4466<p>Additionally, device implementations MAY include reader/writer support for the
4467following MIFARE technologies.</p>
4468
4469<ul>
4470 <li> MIFARE Classic
4471 <li> MIFARE Ultralight
4472 <li> NDEF on MIFARE Classic
4473</ul>
4474
4475<p>Note that Android includes APIs for these MIFARE types. If a device
4476implementation supports MIFARE in the reader/writer role, it:</p>
4477
4478<ul>
4479 <li> MUST implement the corresponding Android APIs as documented by the Android SDK
4480 <li> MUST report the feature com.nxp.mifare from the
4481android.content.pm.PackageManager.hasSystemFeature() meth<a href="http://developer.android.com/reference/android/content/pm/PackageManager.html">od [Resources, 53]</a>. Note that this is not a standard Android feature and as such does not appear
4482as a constant on the PackageManager class.
4483 <li> MUST NOT implement the corresponding Android APIs nor report the com.nxp.mifare
4484feature unless it also implements general NFC support as described in this
4485section
4486</ul>
4487
4488<p>If a device implementation does not include NFC hardware, it MUST NOT declare
4489the android.hardware.nfc feature from the
4490android.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>
4491
4492<p>As the classes android.nfc.NdefMessage and android.nfc.NdefRecord represent a
4493protocol-independent data representation format, device implementations MUST
4494implement these APIs even if they do not include support for NFC or declare the
4495android.hardware.nfc feature.</p>
4496
4497<h3 id=7_4_5_minimum_network_capability>7.4.5. Minimum Network Capability</h3>
4498
4499
4500<p>Device implementations MUST include support for one or more forms of data
4501networking. Specifically, device implementations MUST include support for at
4502least one data standard capable of 200Kbit/sec or greater. Examples of
4503technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g,
4504Ethernet, Bluetooth PAN, etc.</p>
4505
4506<p>Device implementations where a physical networking standard (such as Ethernet)
4507is the primary data connection SHOULD also include support for at least one
4508common wireless data standard, such as 802.11 (Wi-Fi).</p>
4509
4510<p>Devices MAY implement more than one form of data connectivity.</p>
4511
4512<h3 id=7_4_6_sync_settings>7.4.6. Sync Settings</h3>
4513
4514
4515<p>Device implementations MUST have the master auto-sync setting on by default so
4516that the method getMasterSyncAutomatically() returns "true" [<a href="http://developer.android.com/reference/android/content/ContentResolver.html">Resources, 89</a>].</p>
4517
4518<h2 id=7_5_cameras>7.5. Cameras</h2>
4519
4520
4521<p>Device implementations SHOULD include a rear-facing camera and MAY include a
4522front-facing camera. A rear-facing camera is a camera located on the side of
4523the device opposite the display; that is, it images scenes on the far side of
4524the device, like a traditional camera. A front-facing camera is a camera
4525located on the same side of the device as the display; that is, a camera
4526typically used to image the user, such as for video conferencing and similar
4527applications.</p>
4528
4529<p>If a device implementation includes at least one camera, it SHOULD be possible
4530for an application to simultaneously allocate 3 bitmaps equal to the size of
4531the images produced by the largest-resolution camera sensor on the device.</p>
4532
4533<h3 id=7_5_1_rear-facing_camera>7.5.1. Rear-Facing Camera</h3>
4534
4535
4536<p>Device implementations SHOULD include a rear-facing camera. If a device
4537implementation includes at least one rear-facing camera, it:</p>
4538
4539<ul>
4540 <li> MUST report the feature flag android.hardware.camera and
4541android.hardware.camera.any
4542 <li> MUST have a resolution of at least 2 megapixels
4543 <li> SHOULD have either hardware auto-focus or software auto-focus implemented in
4544the camera driver (transparent to application software)
4545 <li> MAY have fixed-focus or EDOF (extended depth of field) hardware
4546 <li> MAY include a flash. If the Camera includes a flash, the flash lamp MUST NOT be
4547lit while an android.hardware.Camera.PreviewCallback instance has been
4548registered on a Camera preview surface, unless the application has explicitly
4549enabled the flash by enabling the FLASH_MODE_AUTO or FLASH_MODE_ON attributes
4550of a Camera.Parameters object. Note that this constraint does not apply to the
4551device's built-in system camera application, but only to third-party
4552applications using Camera.PreviewCallback.
4553</ul>
4554
4555<h3 id=7_5_2_front-facing_camera>7.5.2. Front-Facing Camera</h3>
4556
4557
4558<p>Device implementations MAY include a front-facing camera. If a device
4559implementation includes at least one front-facing camera, it:</p>
4560
4561<ul>
4562 <li> MUST report the feature flag android.hardware.camera.any and
4563android.hardware.camera.front
4564 <li> MUST have a resolution of at least VGA (640x480 pixels)
4565 <li> MUST NOT use a front-facing camera as the default for the Camera API. The
4566camera API in Android has specific support for front-facing cameras and device
4567implementations MUST NOT configure the API to to treat a front-facing camera as
4568the default rear-facing camera, even if it is the only camera on the device.
4569 <li> MAY include features (such as auto-focus, flash, etc.) available to rear-facing
4570cameras as described in <a href="#heading=h.v6dmzvarwqkm">section 7.5.1</a>
4571 <li> MUST horizontally reflect (i.e. mirror) the stream displayed by an app in a
4572CameraPreview, as follows:
4573 <ul>
4574 <li> If the device implementation is capable of being rotated by user (such as
4575automatically via an accelerometer or manually via user input), the camera
4576preview MUST be mirrored horizontally relative to the device's current
4577orientation.
4578 <li> If the current application has explicitly requested that the Camera display be
4579rotated 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
4580orientation specified by the application.
4581 <li> Otherwise, the preview MUST be mirrored along the device's default horizontal
4582axis.
4583 </ul>
4584 <li> MUST mirror the image displayed by the postview in the same manner as the
4585camera preview image stream. If the device implementation does not support
4586postview, this requirement obviously does not apply.
4587 <li> MUST NOT mirror the final captured still image or video streams returned to
4588application callbacks or committed to media storage
4589</ul>
4590
4591<h3 id=7_5_3_external_camera>7.5.3. External Camera</h3>
4592
4593
4594<p>Device implementations with USB host mode MAY include support for an external
4595camera that connects to the USB port. If a device includes support for an
4596external camera, it:</p>
4597
4598<ul>
4599 <li> MUST declare the platform feature android.hardware.camera.external and
4600android.hardware camera.any
4601 <li> MUST support USB Video Class (UVC 1.0 or higher)
4602 <li> MAY support multiple cameras
4603</ul>
4604
4605<p>Video compression (such as MJPEG) support is RECOMMENDED to enable transfer of
4606high-quality unencoded streams (i.e. raw or independently compressed picture
4607streams). Camera-based video encoding MAY be supported. If so, a simultaneous
4608unencoded/ MJPEG stream (QVGA or greater resolution) MUST be accessible to the
4609device implementation. </p>
4610
4611<h3 id=7_5_4_camera_api_behavior>7.5.4. Camera API Behavior</h3>
4612
4613
4614<p>Android includes two API packages to access the camera, the newer
4615android.hardware.camera2 API expose lower-level camera control to the app,
4616including efficient zero-copy burst/streaming flows and per-frame controls of
4617exposure, gain, white balance gains, color conversion, denoising, sharpening,
4618and more. </p>
4619
4620<p>The older API package, android.hardware.Camera, is marked as deprecated in
4621Android 5.0 but as it should still be available for apps to use Android device
4622implementations MUST ensure the continued support of the API as described in
4623this section and in the Android SDK.</p>
4624
4625<p>Device implementations MUST implement the following behaviors for the
4626camera-related APIs, for all available cameras:</p>
4627
4628<ul>
4629 <li> If an application has never called
4630android.hardware.Camera.Parameters.setPreviewFormat(int), then the device MUST
4631use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to
4632application callbacks.
4633 <li> If an application registers an android.hardware.Camera.PreviewCallback instance
4634and the system calls the onPreviewFrame() method when the preview format is
4635YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() must further
4636be in the NV21 encoding format. That is, NV21 MUST be the default.
4637 <li> For android.hardware.Camera, device implementations MUST support the YV12
4638format (as denoted by the android.graphics.ImageFormat.YV12 constant) for
4639camera previews for both front- and rear-facing cameras. (The hardware video
4640encoder and camera may use any native pixel format, but the device
4641implementation MUST support conversion to YV12.)
4642 <li> For android.hardware.camera2, device implementations must support the
4643android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG
4644formats as outputs through the android.media.ImageReader API.
4645</ul>
4646
4647<p>Device implementations MUST still implement the full Camera API included in the
4648Android 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
4649capabilities. For instance, cameras that lack autofocus MUST still call any
4650registered android.hardware.Camera.AutoFocusCallback instances (even though
4651this has no relevance to a non-autofocus camera.) Note that this does apply to
4652front-facing cameras; for instance, even though most front-facing cameras do
4653not support autofocus, the API callbacks must still be "faked" as described.</p>
4654
4655<p>Device implementations MUST recognize and honor each parameter name defined as
4656a constant on the android.hardware.Camera.Parameters class, if the underlying
4657hardware supports the feature. If the device hardware does not support a
4658feature, the API must behave as documented. Conversely, device implementations
4659MUST NOT honor or recognize string constants passed to the
4660android.hardware.Camera.setParameters() method other than those documented as
4661constants on the android.hardware.Camera.Parameters. That is, device
4662implementations MUST support all standard Camera parameters if the hardware
4663allows, and MUST NOT support custom Camera parameter types. For instance,
4664device implementations that support image capture using high dynamic range
4665(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>
4666
4667<p>Because not all device implementations can fully support all the features of
4668the android.hardware.camera2 API, device implementations MUST report the proper
4669level of support with the android.info.supportedHardwareLevel property as
4670described 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>
4671
4672<p>Device implementations MUST also declare its Individual camera capabilities of
4673android.hardware.camera2 via the android.request.availableCapabilities property
4674and 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
4675supports the feature. </p>
4676
4677<p>Device implementations MUST broadcast the Camera.ACTION_NEW_PICTURE intent
4678whenever a new picture is taken by the camera and the entry of the picture has
4679been added to the media store.</p>
4680
4681<p>Device implementations MUST broadcast the Camera.ACTION_NEW_VIDEO intent
4682whenever a new video is recorded by the camera and the entry of the picture has
4683been added to the media store.</p>
4684
4685<h3 id=7_5_5_camera_orientation>7.5.5. Camera Orientation</h3>
4686
4687
4688<p>Both front- and rear-facing cameras, if present, MUST be oriented so that the
4689long dimension of the camera aligns with the screen's long dimension. That is,
4690when the device is held in the landscape orientation, cameras MUST capture
4691images in the landscape orientation. This applies regardless of the device's
4692natural orientation; that is, it applies to landscape-primary devices as well
4693as portrait-primary devices.</p>
4694
4695<h2 id=7_6_memory_and_storage>7.6. Memory and Storage</h2>
4696
4697
4698<h3 id=7_6_1_minimum_memory_and_storage>7.6.1. Minimum Memory and Storage</h3>
4699
4700<table>
4701 <tr>
4702 <td class="tab2"></td>
4703 <td>
4704<p>Android Television devices MUST have at least 5GB of non-volatile storage
4705available for application private data.</p>
4706</td>
4707 </tr>
4708</table>
4709
4710
4711<p>The memory available to the kernel and userspace on device implementations MUST
4712be at least equal or larger than the minimum values specified by the following
4713table. (See <a href="#heading=h.6fey5v3qb5m3">section 7.1.1</a> for screen size and density definitions.)</p>
4714<table>
4715 <tr>
4716 <td class="tab0">
4717<p><strong>Density and screen size</strong></p>
4718</td>
4719 <td class="tab0">
4720<p><strong>32-bit device</strong></p>
4721</td>
4722 <td class="tab0">
4723<p><strong>64-bit device</strong></p>
4724</td>
4725 </tr>
4726 <tr>
4727 <td>
4728<p>Android Watch devices (due to smaller screens)</p>
4729</td>
4730 <td>
4731<p>416MB</p>
4732</td>
4733 <td>
4734<p>Not applicable</p>
4735</td>
4736 </tr>
4737 <tr>
4738 <td>
4739<p>xhdpi or lower on small/normal screens</p>
4740
4741<p>hdpi or lower on large screens</p>
4742
4743<p>mdpi or lower on extra large screens</p>
4744</td>
4745 <td>
4746<p>512MB</p>
4747</td>
4748 <td>
4749<p>832MB</p>
4750</td>
4751 </tr>
4752 <tr>
4753 <td>
4754<p>400dpi or higher on small/normal screens</p>
4755
4756<p>xhdpi or higher on large screens</p>
4757
4758<p>tvdpi or higher on extra large screens</p>
4759</td>
4760 <td>
4761<p>896MB</p>
4762</td>
4763 <td>
4764<p>1280MB</p>
4765</td>
4766 </tr>
4767 <tr>
4768 <td>
4769<p>560dpi or higher on small/normal screens</p>
4770
4771<p>400dpi or higher on large screens</p>
4772
4773<p>xhdpi or higher on extra large screens</p>
4774</td>
4775 <td>
4776<p>1344MB</p>
4777</td>
4778 <td>
4779<p>1824MB</p>
4780</td>
4781 </tr>
4782</table>
4783
4784
4785<p>The minimum memory values MUST be in addition to any memory space already
4786dedicated to hardware components such as radio, video, and so on that is not
4787under the kernel's control.</p>
4788
4789<p>Android Television devices MUST have at least 5GB and other device
4790implementations MUST have at least 1.5GB of non-volatile storage available for
4791application private data. That is, the /data partition MUST be at least 5GB for
4792Android Television devices and at least 1.5GB for other device implementations.
4793Device implementations that run Android are <strong>very strongly encouraged</strong> to have at least 3GB of non-volatile storage for application private data so
4794they will be able to upgrade to the future platform releases.</p>
4795
4796<p>The Android APIs include a Download Manager that applications MAY use to
4797download 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
4798downloading individual files of at least 100MB in size to the default "cache"
4799location.</p>
4800
4801<h3 id=7_6_2_application_shared_storage>7.6.2. Application Shared Storage</h3>
4802
4803
4804<p>Device implementations MUST offer shared storage for applications also often
4805referred as “shared external storage”. </p>
4806
4807<p>Device implementations MUST be configured with shared storage mounted by
4808default, "out of the box". If the shared storage is not mounted on the Linux
4809path /sdcard, then the device MUST include a Linux symbolic link from /sdcard
4810to the actual mount point.</p>
4811
4812<p>Device implementations MAY have hardware for user-accessible removable storage,
4813such as a Secure Digital (SD) card slot. If this slot is used to satisfy the
4814shared storage requirement, the device implementation:</p>
4815
4816<ul>
4817 <li> MUST implement a toast or pop-up user interface warning the user when there is
4818no SD card
4819 <li> MUST include a FAT-formatted SD card 1GB in size or larger OR show on the box
4820and other material available at time of purchase that the SD card has to be
4821separately purchased
4822 <li> MUST mount the SD card by default
4823</ul>
4824
4825<p>Alternatively, device implementations MAY allocate internal (non-removable)
4826storage as shared storage for apps as included in the upstream Android Open
4827Source Project; device implementations SHOULD use this configuration and
4828software implementation. If a device implementation uses internal
4829(non-removable) storage to satisfy the shared storage requirement, that storage
4830MUST be 1GB in size or larger and mounted on /sdcard (or /sdcard MUST be a
4831symbolic link to the physical location if it is mounted elsewhere).</p>
4832
4833<p>Device implementations MUST enforce as documented the
4834android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage.
4835Shared storage MUST otherwise be writable by any application that obtains that
4836permission.</p>
4837
4838<p>Device implementations that include multiple shared storage paths (such as both
4839an SD card slot and shared internal storage) MUST NOT allow Android
4840applications to write to the secondary external storage, except for their
4841package-specific directories on the secondary external storage, but SHOULD
4842expose content from both storage paths transparently through Android's media
4843scanner service and android.provider.MediaStore.</p>
4844
4845<p>Regardless of the form of shared storage used, device implementations MUST
4846provide some mechanism to access the contents of shared storage from a host
4847computer, such as USB mass storage (UMS) or Media Transfer Protocol (MTP).
4848Device implementations MAY use USB mass storage, but SHOULD use Media Transfer
4849Protocol. If the device implementation supports Media Transfer Protocol, it:</p>
4850
4851<ul>
4852 <li> SHOULD be compatible with the reference Android MTP host, Android File Transfer
4853[<a href="http://www.android.com/filetransfer">Resources, 96</a>]
4854 <li> SHOULD report a USB device class of 0x00
4855 <li> SHOULD report a USB interface name of 'MTP'
4856</ul>
4857
4858<p>If the device implementation lacks USB ports, it MUST provide a host computer
4859with access to the contents of shared storage by some other means, such as a
4860network file system.</p>
4861
4862<h2 id=7_7_usb>7.7. USB</h2>
4863
4864
4865<p>Device implementations SHOULD support USB peripheral mode and SHOULD support
4866USB host mode.</p>
4867
4868<p>If a device implementation includes a USB port supporting peripheral mode:</p>
4869
4870<ul>
4871 <li> The port MUST be connectable to a USB host that has a standard type-A or type
4872-C USB port.
4873 <li> The port SHOULD use micro-A, micro-AB or type-C USB form factor. Existing and
4874new Android devices are <strong>very strongly encouraged to meet these requirements</strong> so they will be able to upgrade to the future platform releases.
4875 <li> The port SHOULD be centered in the middle of an edge. Device implementations
4876SHOULD either locate the port on the bottom of the device (according to natural
4877orientation) or enable software screen rotation for all apps (including home
4878screen), so that the display draws correctly when the device is oriented with
4879the 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.
4880 <li> It MUST allow a USB host connected with the Android device to access the
4881contents of the shared storage volume using either USB mass storage or Media
4882Transfer Protocol, if the device reports the android.hardware.feature.output
4883feature or the android.hardware.camera feature.
4884 <li> It SHOULD implement the Android Open Accessory (AOA) API and specification as
4885documented in the Android SDK documentation, and if it is an Android Handheld
4886device it MUST implement the AOA API. Device implementations implementing the
4887AOA specification:
4888 <ul>
4889 <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>]
4890 <li> MUST implement the USB audio class as documented in the Android SDK
4891documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>]
4892 </ul>
4893 <li> It SHOULD implement support to draw 1.5 A current during HS chirp and traffic
4894as 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.
4895 <li> The value of iSerialNumber in USB standard device descriptor MUST be equal to
4896the value of android.os.Build.SERIAL.
4897</ul>
4898
4899<p>If a device implementation includes a USB port supporting host mode, it:</p>
4900
4901<ul>
4902 <li> SHOULD use a type-C USB port, if the device implementation supports USB 3.1
4903 <li> MAY use a non-standard port form factor, but if so MUST ship with a cable or
4904cables adapting the port to a standard type-A or type-C USB port
4905 <li> MAY use a micro-AB USB port, but if so SHOULD ship with a cable or cables
4906adapting the port to a standard type-A or type-C USB port
4907 <li> is <strong>very strongly RECOMMENDED</strong> to implement the USB audio class as documented in the Android SDK
4908documentation [<a href="http://developer.android.com/reference/android/hardware/usb/UsbConstants.html#USB_CLASS_AUDIO">Resources, 98</a>]
4909 <li> MUST implement the Android USB host API as documented in the Android SDK, and
4910MUST 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>]
4911 <li> SHOULD support the Charging Downstream Port output current range of 1.5 A ~ 5 A
4912as 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>]
4913</ul>
4914
4915<h2 id=7_8_audio>7.8. Audio</h2>
4916
4917
4918<h3 id=7_8_1_microphone>7.8.1. Microphone</h3>
4919
4920<table>
4921 <tr>
4922 <td class="tab2"></td>
4923 <td>
4924<p>Android Handheld and Watch devices MUST include a microphone.</p>
4925</td>
4926 </tr>
4927</table>
4928
4929
4930<p>Device implementations MAY omit a microphone. However, if a device
4931implementation omits a microphone, it MUST NOT report the
4932android.hardware.microphone feature constant, and MUST implement the audio
4933recording API at least as no-ops, per <a href="#heading=h.5h5uvpadidzr">section 7</a>. Conversely, device implementations that do possess a microphone:</p>
4934
4935<ul>
4936 <li> MUST report the android.hardware.microphone feature constant
4937 <li> MUST meet the audio recording requirements in <a href="#heading=h.q24elivs4xtv">section 5.4</a>
4938 <li> MUST meet the audio latency requirements in <a href="#heading=h.1p55xhbym9l4">section 5.6</a>
4939</ul>
4940
4941<h3 id=7_8_2_audio_output>7.8.2. Audio Output</h3>
4942
4943<table>
4944 <tr>
4945 <td class="tab2"></td>
4946 <td>
4947<p>Android Watch devices MAY include an audio output.</p>
4948</td>
4949 </tr>
4950</table>
4951
4952
4953<p>Device implementations including a speaker or with an audio/multimedia output
4954port for an audio output peripheral as a headset or an external speaker:</p>
4955
4956<ul>
4957 <li> MUST report the android.hardware.audio.output feature constant
4958 <li> MUST meet the audio playback requirements in <a href="#heading=h.1xocvxnwynnm">section 5.5</a>
4959 <li> MUST meet the audio latency requirements in <a href="#heading=h.1p55xhbym9l4">section 5.6</a>
4960</ul>
4961
4962<p>Conversely, if a device implementation does not include a speaker or audio
4963output port, it MUST NOT report the android.hardware.audio output feature, and
4964MUST implement the Audio Output related APIs as no-ops at least. </p>
4965
4966<p>Android Watch device implementation MAY but SHOULD NOT have audio output, but
4967other types of Android device implementations MUST have an audio output and
4968declare android.hardware.audio.output.</p>
4969
4970<h4 id=7_8_2_1_analog_audio_ports>7.8.2.1. Analog Audio Ports</h4>
4971
4972
4973<p>In order to be compatible with the headsets and other audio accessories using
4974the 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
4975one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack. If a device
4976implementation has a 4 conductor 3.5mm audio jack, it:</p>
4977
4978<ul>
4979 <li> MUST support audio playback to stereo headphones and stereo headsets with a
4980microphone, and SHOULD support audio recording from stereo headsets with a
4981microphone
4982 <li> MUST support TRRS audio plugs with the CTIA pin-out order, and SHOULD support
4983audio plugs with the OMTP pin-out order
4984 <li> MUST support the detection of microphone on the plugged in audio accessory, if
4985the device implementation supports a microphone, and broadcast the
4986android.intent.action.HEADSET_PLUG with the extra value microphone set as 1
4987 <li> SHOULD support the detection and mapping to the keycodes for the following 3
4988ranges of equivalent impedance between the microphone and ground conductors on
4989the audio plug:
4990 <ul>
4991 <li> <strong>70 ohm or less</strong>: KEYCODE_HEADSETHOOK
4992 <li> <strong>210–290 Ohm</strong>:<strong> </strong>KEYCODE_VOLUME_UP
4993 <li> <strong>360–680 Ohm</strong>: KEYCODE_VOLUME_DOWN
4994 </ul>
4995 <li> SHOULD support the detection and mapping to the keycode for the following range
4996of equivalent impedance between the microphone and ground conductors on the
4997audio plug:
4998 <ul>
4999 <li> <strong>110–180 Ohm: </strong>KEYCODE_VOICE_ASSIST
5000 </ul>
5001 <li> MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all
5002contacts on plug are touching their relevant segments on the jack
5003 <li> MUST be capable of driving at least 150mV +/- 10% of output voltage on a 32 Ohm
5004speaker impedance
5005 <li> MUST have a microphone bias voltage between 1.8V ~ 2.9V
5006</ul>
5007
5008<h1 id=8_performance_compatibility>8. Performance Compatibility</h1>
5009
5010
5011<p>Some minimum performance criterias are critical to the user experience and
5012impacts the baseline assumptions developers would have when developing an app.
5013Android Watch devices SHOULD and other type of device implementations MUST meet
5014the following criteria:</p>
5015
5016<h2 id=8_1_user_experience_consistency>8.1. User Experience Consistency</h2>
5017
5018
5019<p>Device implementations MUST provide a smooth user interface by ensuring a
5020consistent frame rate and response times for applications and games. Device
5021implementations MUST meet the following requirements: </p>
5022
5023<ul>
5024 <li> <strong>Consistent frame latency</strong>—Inconsistent frame latency or a delay to render frames MUST NOT happen more
5025often than 5 frames in a second, and SHOULD be below 1 frames in a second.
5026 <li> <strong>User interface latency</strong>—Device implementations MUST ensure low latency user experience by scrolling a
5027list of 10K list entries as defined by the Android Compatibility Test Suite
5028(CTS) in less than 36 secs.
5029 <li> <strong>Task switching</strong>—When multiple applications have been launched, re-launching an already-running
5030application after it has been launched MUST take less than 1 second.
5031</ul>
5032
5033<h2 id=8_2_file_i_o_access_performance>8.2. File I/O Access Performance</h2>
5034
5035
5036<p>Device implementations MUST ensure file access performance consistency for read
5037and write operations. </p>
5038
5039<ul>
5040 <li> <strong>Sequential write</strong>—Device implementations MUST ensure a sequential write performance of 10MB/s
5041for a 256MB file using 10MB write buffer.
5042 <li> <strong>Random write</strong>—Device implementations MUST ensure a random write performance of 0.5MB/s for a
5043256MB file using 4KB write buffer.
5044 <li> <strong>Sequential read</strong>—Device implementations MUST ensure a sequential read performance of 15MB/s for
5045a 256MB file using 10MB write buffer.
5046 <li> <strong>Random read</strong>—Device implementations MUST ensure a random read performance of 3.5MB/s for a
5047256MB file using 4KB write buffer.
5048</ul>
5049
5050<h1 id=9_security_model_compatibility>9. Security Model Compatibility</h1>
5051
5052
5053<p>Device implementations MUST implement a security model consistent with the
5054Android platform security model as defined in Security and Permissions
5055reference 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
5056installation of self-signed applications without requiring any additional
5057permissions/certificates from any third parties/authorities. Specifically,
5058compatible devices MUST support the security mechanisms described in the follow
5059subsections.</p>
5060
5061<h2 id=9_1_permissions>9.1. Permissions</h2>
5062
5063
5064<p>Device implementations MUST support the Android permissions model as defined in
5065the 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
5066described in the SDK documentation; no permissions may be omitted, altered, or
5067ignored. Implementations MAY add additional permissions, provided the new
5068permission ID strings are not in the android.* namespace.</p>
5069
5070<h2 id=9_2_uid_and_process_isolation>9.2. UID and Process Isolation</h2>
5071
5072
5073<p>Device implementations MUST support the Android application sandbox model, in
5074which each application runs as a unique Unixstyle UID and in a separate
5075process. Device implementations MUST support running multiple applications as
5076the same Linux user ID, provided that the applications are properly signed and
5077constructed, as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
5078
5079<h2 id=9_3_filesystem_permissions>9.3. Filesystem Permissions</h2>
5080
5081
5082<p>Device implementations MUST support the Android file access permissions model
5083as defined in the Security and Permissions reference [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>].</p>
5084
5085<h2 id=9_4_alternate_execution_environments>9.4. Alternate Execution Environments</h2>
5086
5087
5088<p>Device implementations MAY include runtime environments that execute
5089applications using some other software or technology than the Dalvik Executable
5090Format or native code. However, such alternate execution environments MUST NOT
5091compromise the Android security model or the security of installed Android
5092applications, as described in this section.</p>
5093
5094<p>Alternate runtimes MUST themselves be Android applications, and abide by the
5095standard Android security model, as described elsewhere in <a href="#heading=h.a32osmf1tmwt">section 9</a>.</p>
5096
5097<p>Alternate runtimes MUST NOT be granted access to resources protected by
5098permissions not requested in the runtime's AndroidManifest.xml file via the
5099<uses-permission> mechanism.</p>
5100
5101<p>Alternate runtimes MUST NOT permit applications to make use of features
5102protected by Android permissions restricted to system applications.</p>
5103
5104<p>Alternate runtimes MUST abide by the Android sandbox model. Specifically,
5105alternate runtimes:</p>
5106
5107<ul>
5108 <li> SHOULD install apps via the PackageManager into separate Android sandboxes (
5109Linux user IDs, etc.)
5110 <li> MAY provide a single Android sandbox shared by all applications using the
5111alternate runtime
5112 <li> and installed applications using an alternate runtime, MUST NOT reuse the
5113sandbox of any other app installed on the device, except through the standard
5114Android mechanisms of shared user ID and signing certificate
5115 <li> MUST NOT launch with, grant, or be granted access to the sandboxes
5116corresponding to other Android applications
5117 <li> MUST NOT be launched with, be granted, or grant to other applications any
5118privileges of the superuser (root), or of any other user ID
5119</ul>
5120
5121<p>The .apk files of alternate runtimes MAY be included in the system image of a
5122device implementation, but MUST be signed with a key distinct from the key used
5123to sign other applications included with the device implementation.</p>
5124
5125<p>When installing applications, alternate runtimes MUST obtain user consent for
5126the Android permissions used by the application. If an application needs to
5127make use of a device resource for which there is a corresponding Android
5128permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the
5129user that the application will be able to access that resource. If the runtime
5130environment does not record application capabilities in this manner, the
5131runtime environment MUST list all permissions held by the runtime itself when
5132installing any application using that runtime.</p>
5133
5134<h2 id=9_5_multi-user_support>9.5. Multi-User Support</h2>
5135
5136<table>
5137 <tr>
5138 <td class="tab2"></td>
5139 <td>
5140<p>This feature is optional for all device types.</p>
5141</td>
5142 </tr>
5143</table>
5144
5145
5146<p>Android includes support for multiple users and provides support for full user
5147isolation [<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
5148the following requirements related to multi-user support [<a href="http://source.android.com/devices/tech/storage">Resources, 104</a>]:</p>
5149
5150<ul>
5151 <li> Device implementations that do not declare the android.hardware.telephony
5152feature flag MUST support restricted profiles, a feature that allows device
5153owners to manage additional users and their capabilities on the device. With
5154restricted profiles, device owners can quickly set up separate environments for
5155additional users to work in, with the ability to manage finer-grained
5156restrictions in the apps that are available in those environments.
5157 <li> Conversely device implementations that declare the android.hardware.telephony
5158feature flag MUST NOT support restricted profiles but MUST align with the AOSP
5159implementation of controls to enable /disable other users from accessing the
5160voice calls and SMS.
5161 <li> Device implementations MUST, for each user, implement a security model
5162consistent with the Android platform security model as defined in Security and
5163Permissions reference document in the APIs [<a href="http://developer.android.com/guide/topics/security/permissions.html">Resources, 102</a>]
5164 <li> Device implementations MAY support creating users and managed profiles via the
5165android.app.admin.DevicePolicyManager APIs, and if supported, MUST declare the
5166platform feature flag android.software.managed_users.
5167 <li> Device implementations that declare the feature flag
5168android.software.managed_users MUST use the upstream AOSP icon badge to
5169represent the managed applications and other badge UI elements like Recents &
5170Notifications.
5171 <li> Each user instance on an Android device MUST have separate and isolated
5172external storage directories. Device implementations MAY store multiple users'
5173data on the same volume or filesystem. However, the device implementation MUST
5174ensure that applications owned by and running on behalf a given user cannot
5175list, read, or write to data owned by any other user. Note that removable
5176media, such as SD card slots, can allow one user to access another's data by
5177means of a host PC. For this reason, device implementations that use removable
5178media for the external storage APIs MUST encrypt the contents of the SD card if
5179multiuser is enabled using a key stored only on non-removable media accessible
5180only to the system. As this will make the media unreadable by a host PC, device
5181implementations will be required to switch to MTP or a similar system to
5182provide host PCs with access to the current user's data. Accordingly, device
5183implementations MAY but SHOULD NOT enable multi-user if they use removable
5184media [<a href="http://developer.android.com/reference/android/os/Environment.html">Resources, 105</a>] for primary external storage.
5185</ul>
5186
5187<h2 id=9_6_premium_sms_warning>9.6. Premium SMS Warning</h2>
5188
5189
5190<p>Android includes support for warning users of any outgoing premium SMS message
5191[<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
5192carrier that may incur a charge to the user. Device implementations that
5193declare support for android.hardware.telephony MUST warn users before sending a
5194SMS message to numbers identified by regular expressions defined in
5195/data/misc/sms/codes.xml file in the device. The upstream Android Open Source
5196Project provides an implementation that satisfies this requirement.</p>
5197
5198<h2 id=9_7_kernel_security_features>9.7. Kernel Security Features</h2>
5199
5200
5201<p>The Android Sandbox includes features that can use the Security-Enhanced Linux
5202(SELinux) mandatory access control (MAC) system and other security features in
5203the Linux kernel. SELinux or any other security features, if implemented below
5204the Android framework:</p>
5205
5206<ul>
5207 <li> MUST maintain compatibility with existing applications
5208 <li> MUST NOT have a visible user interface when a security violation is detected
5209and successfully blocked, but MAY have a visible user interface when an
5210unblocked security violation occurs resulting in a successful exploit
5211 <li> SHOULD NOT be user or developer configurable
5212</ul>
5213
5214<p>If any API for configuration of policy is exposed to an application that can
5215affect another application (such as a Device Administration API), the API MUST
5216NOT allow configurations that break compatibility. </p>
5217
5218<p>Devices MUST implement SELinux or an equivalent mandatory access control system
5219if using a kernel other than Linux and meet the following requirements, which
5220are satisfied by the reference implementation in the upstream Android Open
5221Source Project.</p>
5222
5223<p>Device implementations:</p>
5224
5225<ul>
5226 <li> MUST support a SELinux policy that allows the SELinux mode to be set on a
5227per-domain basis, and MUST configure all domains in enforcing mode. No
5228permissive mode domains are allowed, including domains specific to a
5229device/vendor
5230 <li> SHOULD load policy from /sepolicy file on the device
5231 <li> MUST NOT modify, omit, or replace the neverallow rules present within the
5232sepolicy file provided in the upstream Android Open Source Project (AOSP) and
5233the policy MUST compile with all neverallow present, for both AOSP SELinux
5234domains as well as device/vendor specific domains
5235 <li> MUST support dynamic updates of the SELinux policy file without requiring a
5236system image update
5237</ul>
5238
5239<p>Device implementations SHOULD retain the default SELinux policy provided in the
5240upstream Android Open Source Project, until they have first audited their
5241additions to the SELinux policy. Device implementations MUST be compatible with
5242the upstream Android Open Source Project.</p>
5243
5244<h2 id=9_8_privacy>9.8. Privacy</h2>
5245
5246
5247<p>If the device implements functionality in the system that captures the contents
5248displayed on the screen and/or records the audio stream played on the device,
5249it MUST continuously notify the user whenever this functionality is enabled and
5250actively capturing/recording.</p>
5251
5252<h2 id=9_9_full-disk_encryption>9.9. Full-Disk Encryption</h2>
5253
5254<table>
5255 <tr>
5256 <td class="tab2"></td>
5257 <td>
5258<p>Optional for Android device implementations without a lock screen.</p>
5259</td>
5260 </tr>
5261</table>
5262
5263
5264<p>If the device implementation has a lock screen, the device MUST support
5265full-disk encryption of the application private data, (/data partition) as well
5266as the SD card partition if it is a permanent, non-removable part of the device
5267[<a href="http://source.android.com/devices/tech/encryption/index.html">Resources, 107</a>]. For devices supporting full-disk encryption, the full-disk encryption SHOULD
5268be enabled all the time after the user has completed the out-of-box experience.
5269While this requirement is stated as SHOULD for this version of the Android
5270platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android.
5271Encryption MUST use AES with a key of 128-bits (or greater) and a mode designed
5272for storage (for example, AES-XTS, AES-CBC-ESSIV). The encryption key MUST NOT
5273be written to storage at any time without being encrypted. Other than when in
5274active use, the encryption key SHOULD be AES encrypted with the lockscreen
5275passcode stretched using a slow stretching algorithm (e.g. PBKDF2 or scrypt).
5276If the user has not specified a lockscreen passcode or has disabled use of the
5277passcode for encryption, the system SHOULD use a default passcode to wrap the
5278encryption key. If the device provides a hardware-backed keystore, the password
5279stretching algorithm MUST be cryptographically bound to that keystore. The
5280encryption key MUST NOT be sent off the device (even when wrapped with the user
5281passcode and/or hardware bound key). The upstream Android Open Source project
5282provides a preferred implementation of this feature based on the linux kernel
5283feature dm-crypt.</p>
5284
5285<h2 id=9_10_verified_boot>9.10. Verified Boot</h2>
5286
5287
5288<p>Device implementations SHOULD support verified boot for device integrity, and
5289if the feature is supported it MUST declare the platform feature flag
5290android.software.verified_boot. While this requirement is stated as SHOULD for
5291this version of the Android platform, it is <strong>very strongly RECOMMENDED</strong> as we expect this to change to MUST in the future versions of Android. The
5292upstream Android Open Source Project provides a preferred implementation of
5293this feature based on the linux kernel feature dm-verity.</p>
5294
5295<h1 id=10_software_compatibility_testing>10. Software Compatibility Testing</h1>
5296
5297
5298<p>Device implementations MUST pass all tests described in this section.</p>
5299
5300<p>However, note that no software test package is fully comprehensive. For this
5301reason, device implementers are <strong>very strongly encouraged</strong> to make the minimum number of changes as possible to the reference and
5302preferred implementation of Android available from the Android Open Source
5303Project. This will minimize the risk of introducing bugs that create
5304incompatibilities requiring rework and potential device updates.</p>
5305
5306<h2 id=10_1_compatibility_test_suite>10.1. Compatibility Test Suite</h2>
5307
5308
5309<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
5310software on the device. Additionally, device implementers SHOULD use the
5311reference implementation in the Android Open Source tree as much as possible,
5312and MUST ensure compatibility in cases of ambiguity in CTS and for any
5313reimplementations of parts of the reference source code.</p>
5314
5315<p>The CTS is designed to be run on an actual device. Like any software, the CTS
5316may itself contain bugs. The CTS will be versioned independently of this
5317Compatibility Definition, and multiple revisions of the CTS may be released for
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]5318Android 5.1. Device implementations MUST pass the latest CTS version available
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]5319at the time the device software is completed.</p>
5320
5321<h2 id=10_2_cts_verifier>10.2. CTS Verifier</h2>
5322
5323
5324<p>Device implementations MUST correctly execute all applicable cases in the CTS
5325Verifier. The CTS Verifier is included with the Compatibility Test Suite, and
5326is intended to be run by a human operator to test functionality that cannot be
5327tested by an automated system, such as correct functioning of a camera and
5328sensors.</p>
5329
5330<p>The CTS Verifier has tests for many kinds of hardware, including some hardware
5331that is optional. Device implementations MUST pass all tests for hardware that
5332they possess; for instance, if a device possesses an accelerometer, it MUST
5333correctly execute the Accelerometer test case in the CTS Verifier. Test cases
5334for features noted as optional by this Compatibility Definition Document MAY be
5335skipped or omitted.</p>
5336
5337<p>Every device and every build MUST correctly run the CTS Verifier, as noted
5338above. However, since many builds are very similar, device implementers are not
5339expected to explicitly run the CTS Verifier on builds that differ only in
5340trivial ways. Specifically, device implementations that differ from an
5341implementation that has passed the CTS Verifier only by the set of included
5342locales, branding, etc. MAY omit the CTS Verifier test.</p>
5343
5344<h1 id=11_updatable_software>11. Updatable Software</h1>
5345
5346
5347<p>Device implementations MUST include a mechanism to replace the entirety of the
5348system software. The mechanism need not perform "live" upgrades—that is, a
5349device restart MAY be required.</p>
5350
5351<p>Any method can be used, provided that it can replace the entirety of the
5352software preinstalled on the device. For instance, any of the following
5353approaches will satisfy this requirement:</p>
5354
5355<ul>
5356 <li> Over-the-air (OTA) downloads with offline update via reboot
5357 <li> "Tethered" updates over USB from a host PC
5358 <li> "Offline" updates via a reboot and update from a file on removable storage
5359</ul>
5360
5361<p>However, if the device implementation includes support for an unmetered data
5362connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile, the
5363device MUST support Over-the-air download with offline update via reboot.</p>
5364
5365<p>The update mechanism used MUST support updates without wiping user data. That
5366is, the update mechanism MUST preserve application private data and application
5367shared data. Note that the upstream Android software includes an update
5368mechanism that satisfies this requirement.</p>
5369
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]5370<p>For device implementations that are launching with Android 5.1 and later, the
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]5371update mechanism SHOULD support verifying that the system image is binary
5372identical to expected result following an OTA. The block-based OTA
5373implementation in the upstream Android Open Source Project, added since Android
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]53745.1, satisfies this requirement.</p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]5375
5376<p>If an error is found in a device implementation after it has been released but
5377within its reasonable product lifetime that is determined in consultation with
5378the Android Compatibility Team to affect the compatibility of third-party
5379applications, the device implementer MUST correct the error via a software
5380update available that can be applied per the mechanism just described.</p>
5381
5382<h1 id=12_document_changelog>12. Document Changelog</h1>
5383
5384
5385<p>The following table contains a summary of the changes to the Compatibility
5386Definition in this release. </p>
5387<table>
5388 <tr>
5389 <td class="tab0">
5390<p><strong>Section(s)</strong></p>
5391</td>
5392 <td class="tab0">
5393<p><strong>Summary of change</strong></p>
5394</td>
5395 </tr>
5396 <tr>
5397 <td>
5398<p>1. Introduction</p>
5399</td>
5400 <td>
5401<p>Updated requirements to refer to SDK documentation as source of truth.</p>
5402</td>
5403 </tr>
5404 <tr>
5405 <td>
5406<p>2. Device Types</p>
5407</td>
5408 <td>
5409<p>Included definitions for device types for handheld, television, and watch
5410devices.</p>
5411</td>
5412 </tr>
5413 <tr>
5414 <td>
5415<p>2.1 Device Configuration</p>
5416</td>
5417 <td>
5418<p>Added non-exhaustive list to illustrate hardware configuration deviation across
5419devices.</p>
5420</td>
5421 </tr>
5422 <tr>
5423 <td>
5424<p>3.1. Managed API Compatibility</p>
5425</td>
5426 <td>
5427<p>MUST also provide complete implementations of APIs with "@SystemApi" marker in
5428the upstream Android source code.</p>
5429</td>
5430 </tr>
5431 <tr>
5432 <td>
5433<p>3.2.2. Build Parameters</p>
5434</td>
5435 <td>
5436<p>Included SUPPORTED_ABIS, SUPPORTED_32_BIT_ABIS, and SUPPORTED_64_BIT_ABIS
5437parameters in list, updated PRODUCT to require unique Product SKUs, and updated
5438TAGS.</p>
5439</td>
5440 </tr>
5441 <tr>
5442 <td>
5443<p>3.2.3.1. Core Application Intents</p>
5444</td>
5445 <td>
5446<p>Clarified language that the compatibility requirement is for mainly the intents
5447pattern </p>
5448</td>
5449 </tr>
5450 <tr>
5451 <td>
5452<p>3.2.3.5. Default App Settings</p>
5453</td>
5454 <td>
5455<p>Included new requirements for home screen, NFC, and default SMS applications.</p>
5456</td>
5457 </tr>
5458 <tr>
5459 <td>
5460<p>3.3.1 Application Binary Interfaces</p>
5461</td>
5462 <td>
5463<p>Added requirements to support equivalent 32-bit ABI if any 64-bit ABI is
5464supported. Updated parameters to reflect this change.</p>
5465</td>
5466 </tr>
5467 <tr>
5468 <td>
5469<p>3.4.1. WebView Compatibility</p>
5470</td>
5471 <td>
5472<p>Webview compatibility required for all devices except Android Watch devices.
5473Removed Locale string requirement.</p>
5474</td>
5475 </tr>
5476 <tr>
5477 <td>
5478<p>3.4.2. Browser compatibility</p>
5479</td>
5480 <td>
5481<p>Android Television and Watch Devices MAY omit a browser application, but all
5482other types of device implementations MUST include one.</p>
5483</td>
5484 </tr>
5485 <tr>
5486 <td>
5487<p>3.7. Runtime compatibility</p>
5488</td>
5489 <td>
5490<p>Updated Minimum application memory requirements</p>
5491</td>
5492 </tr>
5493 <tr>
5494 <td>
5495<p>3.8.2. Widgets</p>
5496</td>
5497 <td>
5498<p>Widget support is optional for all device types, but recommended for Handheld
5499Devices.</p>
5500</td>
5501 </tr>
5502 <tr>
5503 <td>
5504<p>3.8.3. Notifications</p>
5505</td>
5506 <td>
5507<p>Expanded definitions for types of supported notifications. </p>
5508</td>
5509 </tr>
5510 <tr>
5511 <td>
5512<p>3.8.4. Search</p>
5513</td>
5514 <td>
5515<p>Android Television devices MUST include global search. All other device types
5516SHOULD.</p>
5517</td>
5518 </tr>
5519 <tr>
5520 <td>
5521<p>3.8.6. Themes</p>
5522</td>
5523 <td>
5524<p>Devices MUST support material theme.</p>
5525</td>
5526 </tr>
5527 <tr>
5528 <td>
5529<p>3.8.7. Live Wallpapers</p>
5530</td>
5531 <td>
5532<p>Devices that include live wallpaper MUST report the platform feature flag
5533android.software.live_wallpaper.</p>
5534</td>
5535 </tr>
5536 <tr>
5537 <td>
5538<p>3.8.8. Activity Switching</p>
5539</td>
5540 <td>
5541<p>Advised requirement to support new Recents User Interface</p>
5542</td>
5543 </tr>
5544 <tr>
5545 <td>
5546<p>3.8.10. Lock Screen Media Remote Control</p>
5547</td>
5548 <td>
5549<p> Remote Control Client API deprecated in favor of the Media Notification
5550Template</p>
5551</td>
5552 </tr>
5553 <tr>
5554 <td>
5555<p>3.8.11. Dreams</p>
5556</td>
5557 <td>
5558<p>Optional for Android Watch devices. Required for all other device types.</p>
5559</td>
5560 </tr>
5561 <tr>
5562 <td>
5563<p>3.8.13 Unicode and font</p>
5564</td>
5565 <td>
5566<p>MUST support Roboto 2 in addition to existing requirements.</p>
5567</td>
5568 </tr>
5569 <tr>
5570 <td>
5571<p>3.12. TV Input Framework</p>
5572</td>
5573 <td>
5574<p>Android Television device implementations MUST support Television Input
5575Framework.</p>
5576</td>
5577 </tr>
5578 <tr>
5579 <td>
5580<p>5.1. Media Codecs</p>
5581</td>
5582 <td>
5583<p>Added 3 sections for Audio, Image, and Video codecs.</p>
5584</td>
5585 </tr>
5586 <tr>
5587 <td>
5588<p>5.4 Audio Recording</p>
5589</td>
5590 <td>
5591<p>Broken into subsections</p>
5592</td>
5593 </tr>
5594 <tr>
5595 <td>
5596<p>5.4.1. Raw audio capture</p>
5597</td>
5598 <td>
5599<p>Defined characteristics for raw audio capture on devices that declare
5600android.hardware.microphone</p>
5601</td>
5602 </tr>
5603 <tr>
5604 <td>
5605<p>5.5. Audio Playback</p>
5606</td>
5607 <td>
5608<p>Added section 5.5. Audio Playback with 2 subsections: 5.5.1 Audio Effects and
56095.5.2. Audio Output Volume</p>
5610</td>
5611 </tr>
5612 <tr>
5613 <td>
5614<p>5.6 Audio Latency</p>
5615</td>
5616 <td>
5617<p>Added definitions and requirements for cold output jitter, cold input jitter,
5618and continuous round-trip latency.</p>
5619</td>
5620 </tr>
5621 <tr>
5622 <td>
5623<p>5.8 Secure Media</p>
5624</td>
5625 <td>
5626<p>Included secure media requirements from 7.1.8. External Displays and added
5627requirements for Android Television.</p>
5628</td>
5629 </tr>
5630 <tr>
5631 <td>
5632<p>6.1. Developer Tools</p>
5633</td>
5634 <td>
5635<p>Updated resources.</p>
5636</td>
5637 </tr>
5638 <tr>
5639 <td>
5640<p>6.2.1. Experimental</p>
5641</td>
5642 <td>
5643<p>Removed section</p>
5644</td>
5645 </tr>
5646 <tr>
5647 <td>
5648<p>7. Hardware Compatibility</p>
5649</td>
5650 <td>
5651<p>Updated to reflect that device implementations MUST consistently report
5652accurate hardware configuration for the same build fingerprint.</p>
5653</td>
5654 </tr>
5655 <tr>
5656 <td>
5657<p>7.1.1.1. Screen Size</p>
5658</td>
5659 <td>
5660<p>Updated to reflect Android Watch devices screen size and that the value can’t
5661change</p>
5662</td>
5663 </tr>
5664 <tr>
5665 <td>
5666<p>7.1.1.2. Screen Aspect Ratio</p>
5667</td>
5668 <td>
5669<p>Updated to reflect Android Watch devices screen aspect ratio (1:1).</p>
5670</td>
5671 </tr>
5672 <tr>
5673 <td>
5674<p>7.1.3. Screen Orientation</p>
5675</td>
5676 <td>
5677<p>Updated to reflect that devices with a fixed orientation landscape screen
5678SHOULD only report that orientation. </p>
5679</td>
5680 </tr>
5681 <tr>
5682 <td>
5683<p>7.1.4. 2D and 3D Graphics Acceleration</p>
5684</td>
5685 <td>
5686<p>Added that Android devices MAY support the Android extension pack. </p>
5687</td>
5688 </tr>
5689 <tr>
5690 <td>
5691<p>(old) 7.1.6. Screen Types</p>
5692</td>
5693 <td>
5694<p>Section Removed </p>
5695</td>
5696 </tr>
5697 <tr>
5698 <td>
5699<p>7.1.6. Screen Technology</p>
5700</td>
5701 <td>
5702<p>Updated pixel aspect ratio (PAR) to be between 0.9 and 1.15. (~15% tolerance)</p>
5703</td>
5704 </tr>
5705 <tr>
5706 <td>
5707<p>7.1.7. External Displays</p>
5708</td>
5709 <td>
5710<p>Moved part of section to section 5.8. Secure Media.</p>
5711</td>
5712 </tr>
5713 <tr>
5714 <td>
5715<p>7.2.2. Non-touch Navigation</p>
5716</td>
5717 <td>
5718<p>Android Television devices MUST support D-pad. </p>
5719</td>
5720 </tr>
5721 <tr>
5722 <td>
5723<p>7.2.3. Navigation keys</p>
5724</td>
5725 <td>
5726<p>Included language for support across different device types. </p>
5727</td>
5728 </tr>
5729 <tr>
5730 <td>
5731<p>7.2.4. Touchscreen input</p>
5732</td>
5733 <td>
5734<p>Android Watch devices MUST support touchscreen input. </p>
5735</td>
5736 </tr>
5737 <tr>
5738 <td>
5739<p>7.2.6. Game Controller Support</p>
5740</td>
5741 <td>
5742<p>Added section with Android Television requirements.</p>
5743</td>
5744 </tr>
5745 <tr>
5746 <td>
5747<p>7.2.7. Remote Control </p>
5748</td>
5749 <td>
5750<p>Added section with Android Television requirements.</p>
5751</td>
5752 </tr>
5753 <tr>
5754 <td>
5755<p>7.3. Sensors</p>
5756</td>
5757 <td>
5758<p>Redefined synthetic sensors as composite sensors and streaming sensors as
5759continuous sensors. Sensors should report event time in nanoseconds.</p>
5760</td>
5761 </tr>
5762 <tr>
5763 <td>
5764<p>7.3.1. Accelerometer</p>
5765</td>
5766 <td>
5767<p>Clarified required sensor types and revised requirement thresholds. </p>
5768</td>
5769 </tr>
5770 <tr>
5771 <td>
5772<p>7.3.2. Magnetometer</p>
5773</td>
5774 <td>
5775<p>Clarified required sensor types and revised requirement thresholds.</p>
5776</td>
5777 </tr>
5778 <tr>
5779 <td>
5780<p>7.3.4. Gyroscope</p>
5781</td>
5782 <td>
5783<p>Clarified required sensor types and revised requirement thresholds.</p>
5784</td>
5785 </tr>
5786 <tr>
5787 <td>
5788<p>7.3.5. Barometer</p>
5789</td>
5790 <td>
5791<p>Changed from MAY to SHOULD implement barometer. MUST implement and report
5792TYPE_PRESSURE sensor.</p>
5793</td>
5794 </tr>
5795 <tr>
5796 <td>
5797<p>7.3.6. Thermometer</p>
5798</td>
5799 <td>
5800<p>Devices MAY include ambient thermometer. MAY but SHOULD NOT include CPU
5801thermometer.</p>
5802</td>
5803 </tr>
5804 <tr>
5805 <td>
5806<p>7.3.8. Proximity Sensor</p>
5807</td>
5808 <td>
5809<p>Devices that can make a voice call and indicate any value other than
5810PHONE_TYPE_NONE in getPhoneType SHOULD include a proximity sensor.</p>
5811</td>
5812 </tr>
5813 <tr>
5814 <td>
5815<p>7.4.2. IEEE 802.11 (Wi-Fi)</p>
5816</td>
5817 <td>
5818<p>Android Television devices MUST include Wi-Fi support. Devices that DO support
5819wifi must report android.hardware.wifi. </p>
5820</td>
5821 </tr>
5822 <tr>
5823 <td>
5824<p>7.4.2.1. Wi-Fi Direct</p>
5825</td>
5826 <td>
5827<p>MUST report the hardware feature android.hardware.wifi.direct.</p>
5828</td>
5829 </tr>
5830 <tr>
5831 <td>
5832<p>7.4.2.2. Wi-Fi Tunneled Direct Link Setup</p>
5833</td>
5834 <td>
5835<p>Android Television devices MUST include support for Wi-Fi TDLS.</p>
5836</td>
5837 </tr>
5838 <tr>
5839 <td>
5840<p>7.5. Cameras</p>
5841</td>
5842 <td>
5843<p>If a device implementation includes at least one camera, it SHOULD be possible
5844for an application to simultaneously allocate 3 bitmaps equal to the size of
5845the images produced by the largest-resolution camera sensor on the device.</p>
5846</td>
5847 </tr>
5848 <tr>
5849 <td>
5850<p>7.5.3. External Cameras</p>
5851</td>
5852 <td>
5853<p>Added requirements that device implementations with USB host mode MAY include
5854support for an external camera.</p>
5855</td>
5856 </tr>
5857 <tr>
5858 <td>
5859<p>7.5.5. Camera System Features</p>
5860</td>
5861 <td>
5862<p>Added list of camera features and when they should be defined. </p>
5863</td>
5864 </tr>
5865 <tr>
5866 <td>
5867<p>7.6.1. Minimum Memory and Storage</p>
5868</td>
5869 <td>
5870<p>Updated requirements for 32- and 64-bit devices. SVELTE memory requirement
5871removed. Devices MUST have at least 1.5GB of non-volatile storage</p>
5872</td>
5873 </tr>
5874 <tr>
5875 <td>
5876<p>7.6.2. Application Shared Storage</p>
5877</td>
5878 <td>
5879<p>Updated requirements for user-accessible removable storage</p>
5880</td>
5881 </tr>
5882 <tr>
5883 <td>
5884<p>7.7. USB</p>
5885</td>
5886 <td>
5887<p>Removed requirements for non-charging ports being on the same edge as the
5888micro-USB port. Updated requirements for Host and Peripheral mode. </p>
5889</td>
5890 </tr>
5891 <tr>
5892 <td>
5893<p>7.8.1. Audio</p>
5894</td>
5895 <td>
5896<p>Moved microphone section here. Added requirements for Audio Output and Audio
5897Analog ports. </p>
5898</td>
5899 </tr>
5900 <tr>
5901 <td>
5902<p>8. Performance Compatibility</p>
5903</td>
5904 <td>
5905<p>Added requirements for user interface consistency.</p>
5906</td>
5907 </tr>
5908 <tr>
5909 <td>
5910<p>9.5. Multi-User Support</p>
5911</td>
5912 <td>
5913<p>Multi-user support feature is optional for all device types. Detailed
5914requirements by device type in section.</p>
5915</td>
5916 </tr>
5917 <tr>
5918 <td>
5919<p>9.7. Kernel Security Features</p>
5920</td>
5921 <td>
5922<p>MAY have a visible user interface when an unblocked security violation occurs
5923resulting in a successful exploit. No permissive mode domains allowed.</p>
5924</td>
5925 </tr>
5926 <tr>
5927 <td>
5928<p>9.9. Full-Disk Encryption</p>
5929</td>
5930 <td>
5931<p>Devices with a lock screen MUST support full-disk encryption. For new devices,
5932full-disk encryption must be enabled out of box. </p>
5933</td>
5934 </tr>
5935 <tr>
5936 <td>
5937<p>9.10 Verified boot</p>
5938</td>
5939 <td>
5940<p>Added section to recommend that Device implementations support verified boot
5941for device integrity.</p>
5942</td>
5943 </tr>
5944 <tr>
5945 <td>
5946<p>10.3. Reference Applications</p>
5947</td>
5948 <td>
5949<p>Removed section from CDD.</p>
5950</td>
5951 </tr>
5952 <tr>
5953 <td>
5954<p>11. Updatable Software</p>
5955</td>
5956 <td>
5957<p>If a device supports 802.11 or Bluetooth PAN (Personal Area Network) profile,
5958then it MUST support Over-the-air download with offline update via reboot.</p>
5959</td>
5960 </tr>
5961 <tr>
5962 <td>
5963<p>14. Resources</p>
5964</td>
5965 <td>
5966<p>Resources moved from section 2 to section 14</p>
5967</td>
5968 </tr>
5969</table>
5970
5971
5972<h1 id=13_contact_us>13. Contact Us</h1>
5973
5974
5975<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
5976does not cover.</p>
5977
5978<h1 id=14_resources>14. Resources</h1>
5979
5980
5981<p>1. IETF RFC2119 Requirement Levels: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a></p>
5982
5983<p>2. Android Open Source Project: <a href="http://source.android.com/">http://source.android.com/</a></p>
5984
5985<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>
5986
5987<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>
5988
5989<p>5. API definitions and documentation: <a href="http://developer.android.com/reference/packages.html">http://developer.android.com/reference/packages.html</a></p>
5990
5991<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>
5992
5993<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>
5994
Unsuk Jungd1ac9fe2015-04-01 08:18:41 -0700[diff] [blame]5995<p>8. Android 5.1 allowed version strings: <a href="http://source.android.com/compatibility/5.1/versions.html">http://source.android.com/compatibility/5.1/versions.html</a></p>
Unsuk Jungbca27492015-04-01 08:08:10 -0700[diff] [blame]5996
5997<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>
5998
5999<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>
6000
6001<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>
6002
6003<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>
6004
6005<p>13. WebView compatibility: <a href="http://www.chromium.org/">http://www.chromium.org/</a></p>
6006
6007<p>14. HTML5: <a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/">http://www.whatwg.org/specs/web-apps/current-work/multipage/</a></p>
6008
6009<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>
6010
6011<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>
6012
6013<p>17. HTML5/W3C geolocation API: <a href="http://www.w3.org/TR/geolocation-API/">http://www.w3.org/TR/geolocation-API/</a></p>
6014
6015<p>18. HTML5/W3C webstorage API: <a href="http://www.w3.org/TR/webstorage/">http://www.w3.org/TR/webstorage/</a></p>
6016
6017<p>19. HTML5/W3C IndexedDB API: <a href="http://www.w3.org/TR/IndexedDB/">http://www.w3.org/TR/IndexedDB/</a></p>
6018
6019<p>20. Dalvik Executable Format and bytecode specification: available in the
6020Android source code, at dalvik/docs</p>
6021
6022<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>
6023
6024<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>
6025
6026<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>
6027
6028<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>
6029
6030<p>25. Notifications Resources: <a href="https://developer.android.com/design/patterns/notifications.html">https://developer.android.com/design/patterns/notifications.html</a> </p>
6031
6032<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>
6033
6034<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>
6035
6036<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>
6037
6038<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>
6039
6040<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>
6041
6042<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>
6043
6044<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>
6045
6046<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>
6047
6048<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>
6049
6050<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>
6051
6052<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>
6053
6054<p>37. Settings.Secure LOCATION_MODE:</p>
6055
6056<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>
6057
6058<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>
6059
6060<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>
6061
6062<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>
6063
6064<p>41. Android Device Owner App:</p>
6065
6066<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>
6067
6068<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>
6069
6070<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>
6071
6072<p>44. Eyes Free project: <a href="http://code.google.com/p/eyes-free">http://code.google.com/p/eyes-free</a></p>
6073
6074<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>
6075
6076<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>
6077
6078<p>47. Reference tool documentation (for adb, aapt, ddms, systrace): <a href="http://developer.android.com/guide/developing/tools/index.html">http://developer.android.com/guide/developing/tools/index.html</a></p>
6079
6080<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>
6081
6082<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>
6083
6084<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>
6085
6086<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>
6087
6088<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>
6089
6090<p>53. Android android.content.pm.PackageManager class and Hardware Features List:</p>
6091
6092<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>
6093
6094<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>
6095
6096<p>55. ADB: <a href="http://developer.android.com/tools/help/adb.html">http://developer.android.com/tools/help/adb.html</a> </p>
6097
6098<p>56. Dumpsys: <a href="https://source.android.com/devices/tech/input/dumpsys.html">https://source.android.com/devices/tech/input/dumpsys.html</a> </p>
6099
6100<p>57. DDMS: <a href="http://developer.android.com/tools/debugging/ddms.html">http://developer.android.com/tools/debugging/ddms.html</a> </p>
6101
6102<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>
6103
6104<p>59. SysyTrace tool: <a href="http://developer.android.com/tools/help/systrace.html">http://developer.android.com/tools/help/systrace.html</a></p>
6105
6106<p>60. Android Application Development-Related Settings:</p>
6107
6108<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>
6109
6110<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>
6111
6112<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>
6113
6114<p>63. RenderScript: <a href="http://developer.android.com/guide/topics/renderscript/">http://developer.android.com/guide/topics/renderscript/</a></p>
6115
6116<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>
6117
6118<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>
6119
6120<p>66. EGL Extension-EGL_ANDROID_RECORDABLE:</p>
6121
6122<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>
6123
6124<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>
6125
6126<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>
6127
6128<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>
6129
6130<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>
6131
6132<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>
6133
6134<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>
6135
6136<p>73. Android Open Source sensors: <a href="http://source.android.com/devices/sensors/">http://source.android.com/devices/sensors/</a></p>
6137
6138<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>
6139
6140<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>
6141
6142<p>76. Android Open Source composite sensors: <a href="http://source.android.com/devices/sensors/composite_sensors.html">http://source.android.com/devices/sensors/composite_sensors.html</a></p>
6143
6144<p>77. Continuous trigger mode: <a href="http://source.android.com/devices/sensors/base_triggers.html#continuous">http://source.android.com/devices/sensors/base_triggers.html#continuous</a></p>
6145
6146<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>
6147
6148<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>
6149
6150<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>
6151
6152<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>
6153
6154<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>
6155
6156<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>
6157
6158<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>
6159
6160<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>
6161
6162<p>86. Android NFC Sharing Settings:</p>
6163
6164<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>
6165
6166<p>87. NFC Connection Handover: <a href="http://www.nfc-forum.org/specs/spec_list/#conn_handover">http://www.nfc-forum.org/specs/spec_list/#conn_handover</a></p>
6167
6168<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>
6169
6170<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>
6171
6172<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>
6173
6174<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>
6175
6176<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>
6177
6178<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>
6179
6180<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>
6181
6182<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>
6183
6184<p>96. Android File Transfer: <a href="http://www.android.com/filetransfer">http://www.android.com/filetransfer</a></p>
6185
6186<p>97. Android Open Accessories: <a href="http://developer.android.com/guide/topics/usb/accessory.html">http://developer.android.com/guide/topics/usb/accessory.html</a></p>
6187
6188<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>
6189
6190<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>
6191
6192<p>100. USB Host API:<a href="http://developer.android.com/guide/topics/usb/host.html"> http://developer.android.com/guide/topics/usb/host.html</a></p>
6193
6194<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>
6195
6196<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>
6197
6198<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>
6199
6200<p>104. External Storage reference: <a href="http://source.android.com/devices/tech/storage">http://source.android.com/devices/tech/storage</a></p>
6201
6202<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>
6203
6204<p>106. SMS Short Code: <a href="http://en.wikipedia.org/wiki/Short_code">http://en.wikipedia.org/wiki/Short_code</a></p>
6205
6206<p>107. Android Open Source Encryption: <a href="http://source.android.com/devices/tech/encryption/index.html">http://source.android.com/devices/tech/encryption/index.html</a></p>
6207
6208<p>108. Android Compatibility Program Overview: <a href="http://source.android.com/compatibility/index.html">http://source.android.com/compatibility/index.html</a></p>
6209
6210<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>
6211
6212<p>110. WebM project: <a href="http://www.webmproject.org/">http://www.webmproject.org/</a> </p>
6213
6214<p>Many of these resources are derived directly or indirectly from the Android
6215SDK, and will be functionally identical to the information in that SDK's
6216documentation. In any cases where this Compatibility Definition or the
6217Compatibility Test Suite disagrees with the SDK documentation, the SDK
6218documentation is considered authoritative. Any technical details provided in
6219the references included above are considered by inclusion to be part of this
6220Compatibility Definition.</p>
6221<div style="page-break-before: always;"></div>
6222
6223<div id="footerContent" xmlns:pdf="https://source.android.com">
6224<pdf:pagenumber/>
6225</div>
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