1 page.title=<uses-feature> 2 parent.title=The AndroidManifest.xml File 3 parent.link=manifest-intro.html 4 @jd:body 5 6 <div id="qv-wrapper"> 7 <div id="qv"> 8 9 10 <h2>In this document</h2> 11 <ol> 12 <li><a href="#market-feature-filtering">Android Market and Feature-Based Filtering</a> 13 <ol> 14 <li><a href="#declared">Filtering based on explicitly declared features</a></li> 15 <li><a href="#implicit">Filtering based on implicit features</a></li> 16 <li><a href="#bt-permission-handling">Special handling for Bluetooth feature</a></li> 17 <li><a href="#testing">Testing the features required by your application</a></li> 18 </ol> 19 </li> 20 <li><a href="#features-reference">Features Reference</a> 21 <ol> 22 <li><a href="#hw-features">Hardware features</a></li> 23 <li><a href="#sw-features">Software features</a></li> 24 <li><a href="#permissions">Permissions that Imply Feature Requirements</a></li> 25 </ol> 26 </li> 27 </ol> 28 </div> 29 </div> 30 31 32 <dl class="xml"> 33 34 <dt>syntax:</dt> 35 <dd> 36 <pre class="stx"><uses-feature android:<a href="#name">name</a>="<em>string</em>" 37 android:<a href="#required">required</a>=["true" | "false"] 38 android:<a href="#glEsVersion">glEsVersion</a>="<em>integer</em>" /></pre> 39 </dd> 40 41 <dt>contained in:</dt> 42 <dd><code><a 43 href="{@docRoot}guide/topics/manifest/manifest-element.html"><manifest></a></code></dd> 44 45 <div class="sidebox-wrapper"> 46 <img id="rule" src="{@docRoot}assets/images/grad-rule-qv.png"> 47 <div id="qv-sub-rule"> 48 <img src="{@docRoot}assets/images/icon_market.jpg" style="float:left;margin:0;padding:0;"> 49 <p style="color:#669999;">Android Market and <code style="color:#669999;"><uses-feature></code> elements</p> 50 <p style="margin-top:1em;">Android Market filters the applications that are visible to users, so 51 that users can see and download only those applications that are compatible with their 52 devices. One of the ways Market filters applications is by feature compatibility.</p> 53 54 <p style="margin-top:1em;">To do this, Market checks the 55 <code><uses-feature></code> elements in each application's manifest, to 56 establish the app's feature needs. Market then shows or hides the application to 57 each user, based on a comparison with the features available on the user's 58 device. </p> 59 60 <p style="margin-top:1em;">By specifying the features that your application requires, 61 you enable Android Market to present your application only to users whose 62 devices meet the application's feature requirements, rather than presenting it 63 to all users. </p> 64 65 <p style="margin-top:1em;" class="caution">For important information about how 66 Android Market uses features as the basis for filtering, please read <a 67 href="#market-feature-filtering">Android Market and Feature-Based Filtering</a>, 68 below.</p> 69 </div> 70 </div> 71 72 <dt>description:</dt> 73 <dd>Declares a single hardware or software feature that is used by the 74 application. 75 76 <p>The purpose of a <code><uses-feature></code> declaration is to inform 77 any external entity of the set of hardware and software features on which your 78 application depends. The element offers a <code>required</code> attribute that 79 lets you specify whether your application requires and cannot function without 80 the declared feature, or whether it prefers to have the feature but can function 81 without it. Because feature support can vary across Android devices, the 82 <code><uses-feature></code> element serves an important role in letting an 83 application describe the device-variable features that it uses.</p> 84 85 <p>The set of available features that your application declares corresponds to 86 the set of feature constants made available by the Android {@link 87 android.content.pm.PackageManager}, which are listed for 88 convenience in the <a href="#features-reference">Features Reference</a> tables 89 at the bottom of this document. 90 91 <p>You must specify each feature in a separate <code><uses-feature></code> 92 element, so if your application requires multiple features, it would declare 93 multiple <code><uses-feature></code> elements. For example, an application 94 that requires both Bluetooth and camera features in the device would declare 95 these two elements:</p> 96 97 <pre> 98 <uses-feature android:name="android.hardware.bluetooth" /> 99 <uses-feature android:name="android.hardware.camera" /> 100 </pre> 101 102 <p>In general, you should always make sure to declare 103 <code><uses-feature></code> elements for all of the features that your 104 application requires.</p> 105 106 <p>Declared <code><uses-feature></code> elements are informational only, meaning 107 that the Android system itself does not check for matching feature support on 108 the device before installing an application. However, other services 109 (such as Android Market) or applications may check your application's 110 <code><uses-feature></code> declarations as part of handling or interacting 111 with your application. For this reason, it's very important that you declare all of 112 the features (from the list below) that your application uses. </p> 113 114 <p>For some features, there may exist a specific attribute that allows you to define 115 a version of the feature, such as the version of Open GL used (declared with 116 <a href="#glEsVersion"><code>glEsVersion</code></a>). Other features that either do or do not 117 exist for a device, such as a camera, are declared using the 118 <a href="#name"><code>name</code></a> attribute.</p> 119 120 121 <p>Although the <code><uses-feature></code> element is only activated for 122 devices running API Level 4 or higher, it is recommended to include these 123 elements for all applications, even if the <a href="uses-sdk-element.html#min"><code>minSdkVersion</code></a> 124 is "3" or lower. Devices running older versions of the platform will simply 125 ignore the element.</p> 126 127 <p class="note"><strong>Note:</strong> When declaring a feature, remember 128 that you must also request permissions as appropriate. For example, you must 129 still request the {@link android.Manifest.permission#CAMERA} 130 permission before your application can access the camera API. Requesting the 131 permission grants your application access to the appropriate hardware and 132 software, while declaring the features used by your application ensures proper 133 device compatibility.</p> 134 135 </dd> 136 137 138 <dt>attributes:</dt> 139 140 <dd> 141 <dl class="attr"> 142 143 <dt><a name="name"></a><code>android:name</code></dt> 144 <dd>Specifies a single hardware or software feature used by the application, 145 as a descriptor string. Valid descriptor values are listed in the <a 146 href="#hw-features">Hardware features</a> and <a href="#sw-features">Software 147 features</a> tables, below. </dd> 148 149 <dt><a name="required"></a><code>android:required</code></dt> <!-- added in api level 5 --> 150 <dd>Boolean value that indicates whether the application requires 151 the feature specified in <code>android:name</code>. 152 153 <ul> 154 <li>When you declare <code>"android:required="true"</code> for a feature, 155 you are specifying that the application <em>cannot function, or is not 156 designed to function</em>, when the specified feature is not present on the 157 device. </li> 158 159 <li>When you declare <code>"android:required="false"</code> for a feature, it 160 means that the application <em>prefers to use the feature</em> if present on 161 the device, but that it <em>is designed to function without the specified 162 feature</em>, if necessary. </li> 163 164 </ul> 165 166 <p>The default value for <code>android:required</code> if not declared is 167 <code>"true"</code>.</p> 168 </dd> 169 170 <dt><a name="glEsVersion"></a><code>android:glEsVersion</code></dt> 171 <dd>The OpenGL ES version required by the application. The higher 16 bits 172 represent the major number and the lower 16 bits represent the minor number. For 173 example, to specify OpenGL ES version 2.0, you would set the value as 174 "0x00020000". To specify OpenGL ES 2.1, if/when such a version were made 175 available, you would set the value as "0x00020001". 176 177 <p>An application should specify at most one <code>android:glEsVersion</code> 178 attribute in its manifest. If it specifies more than one, the 179 <code>android:glEsVersion</code> with the numerically highest value is used and 180 any other values are ignored.</p> 181 182 <p>If an application does not specify an <code>android:glEsVersion</code> 183 attribute, then it is assumed that the application requires only OpenGL ES 1.0, 184 which is supported by all Android-powered devices.</p> 185 186 <p>An application can assume that if a platform supports a given OpenGL ES 187 version, it also supports all numerically lower OpenGL ES versions. Therefore, 188 an application that requires both OpenGL ES 1.0 and OpenGL ES 2.0 must specify 189 that it requires OpenGL ES 2.0.</p> 190 191 <p>An application that can work with any of several OpenGL ES versions should 192 only specify the numerically lowest version of OpenGL ES that it requires. (It 193 can check at run-time whether a higher level of OpenGL ES is available.)</p> 194 </dd> 195 196 </dl> 197 </dd> 198 199 <!-- ##api level indication## --> 200 <dt>introduced in:</dt> 201 <dd>API Level 4</dd> 202 203 <dt>see also:</dt> 204 <dd> 205 <ul> 206 <li>{@link android.content.pm.PackageManager}</li> 207 <li>{@link android.content.pm.FeatureInfo}</li> 208 <li>{@link android.content.pm.ConfigurationInfo}</li> 209 <li><a href="{@docRoot}guide/topics/manifest/uses-permission-element.html"><code><uses-permission></code></a></li> 210 <li><a href="{@docRoot}guide/appendix/market-filters.html">Android Market Filters</a></li> 211 </ul> 212 </dd> 213 214 </dl> 215 216 217 <h2 id="market-feature-filtering">Android Market and Feature-Based Filtering</h2> 218 219 <p>Android Market filters the applications that are visible to users, so that 220 users can see and download only those applications that are compatible with 221 their devices. One of the ways Market filters applications is by feature 222 compatibility.</p> 223 224 <p>To determine an application's feature compatibility with a given user's 225 device, the Android Market service compares:</p> 226 227 <ul> 228 <li>Features required by the application — an application declares features in 229 <code><uses-feature></code> elements in its manifest <br/>with...</li> 230 <li>Features available on the device, in hardware or software — 231 a device reports the features it supports as read-only system properties.</li> 232 </ul> 233 234 <p>To ensure an accurate comparison of features, the Android Package Manager 235 provides a shared set of feature constants that both applications and devices 236 use to declare feature requirements and support. The available feature constants 237 are listed in the <a href="#features-reference">Features Reference</a> tables at 238 the bottom of this document, and in the class documentation for {@link 239 android.content.pm.PackageManager}.</p> 240 241 <p>When the user launches the Market application, the application queries the 242 Package Manager for the list of features available on the device by calling 243 {@link android.content.pm.PackageManager#getSystemAvailableFeatures()}. The 244 Market application then passes the features list up to the Android Market 245 service when establishing the session for the user.</p> 246 247 <p>Each time you upload an application to the Android Market Publisher Site, 248 Android Market scans the application's manifest file. It looks for 249 <code><uses-feature></code> elements and evaluates them in combination 250 with other elements, in some cases, such as <code><uses-sdk></code> and 251 <code><uses-permission></code> elements. After establishing the 252 application's set of required features, it stores that list internally as 253 metadata associated with the application <code>.apk</code> and the application 254 version. </p> 255 256 <p>When a user searches or browses for applications using the Android Market 257 application, the service compares the features needed by each application with 258 the features available on the user's device. If all of an application's required 259 features are present on the device, Android Market allows the user to see the 260 application and potentially download it. If any required feature is not 261 supported by the device, Android Market filters the application so that it is 262 not visible to the user and not available for download. </p> 263 264 <p>Because the features you declare in <code><uses-feature></code> 265 elements directly affect how Android Market filters your application, it's 266 important to understand how Android Market evaluates the application's manifest 267 and establishes the set of required features. The sections below provide more 268 information. </p> 269 270 <h3 id="declared">Filtering based on explicitly declared features</h3> 271 272 <p>An explicitly declared feature is one that your application declares in a 273 <code><uses-feature></code> element. The feature declaration can include 274 an <code>android:required=["true" | "false"]</code> attribute (if you are 275 compiling against API level 5 or higher), which lets you specify whether the 276 application absolutely requires the feature and cannot function properly without 277 it (<code>"true"</code>), or whether the application prefers to use the feature 278 if available, but is designed to run without it (<code>"false"</code>).</p> 279 280 <p>Android Market handles explicitly declared features in this way: </p> 281 282 <ul> 283 <li>If a feature is explicitly declared as being required, Android Market adds 284 the feature to the list of required features for the application. It then 285 filters the application from users on devices that do not provide that feature. 286 For example: 287 <pre><uses-feature android:name="android.hardware.camera" android:required="true" /></pre></li> 288 <li>If a feature is explicitly declared as <em>not</em> being required, Android 289 Market <em>does not</em> add the feature to the list of required features. For 290 that reason, an explicitly declared non-required feature is never considered when 291 filtering the application. Even if the device does not provide the declared 292 feature, Android Market will still consider the application compatible with the 293 device and will show it to the user, unless other filtering rules apply. For 294 example: 295 <pre><uses-feature android:name="android.hardware.camera" android:required="false" /></pre></li> 296 <li>If a feature is explicitly declared, but without an 297 <code>android:required</code> attribute, Android Market assumes that the feature 298 is required and sets up filtering on it. </li> 299 </ul> 300 301 <p>In general, if your application is designed to run on Android 1.6 and earlier 302 versions, the <code>android:required</code> attribute is not available in the 303 API and Android Market assumes that any and all 304 <code><uses-feature></code> declarations are required. </p> 305 306 <p class="note"><strong>Note:</strong> By declaring a feature explicitly and 307 including an <code>android:required="false"</code> attribute, you can 308 effectively disable all filtering on Android Market for the specified feature. 309 </p> 310 311 312 <h3 id="implicit">Filtering based on implicit features</h3> 313 314 <p>An <em>implicit</em> feature is one that an application requires in order to 315 function properly, but which is <em>not</em> declared in a 316 <code><uses-feature></code> element in the manifest file. Strictly 317 speaking, every application should <em>always</em> declare all features that it 318 uses or requires, so the absence of a declaration for a feature used by an 319 application should be considered an error. However, as a safeguard for users and 320 developers, Android Market looks for implicit features in each application and 321 sets up filters for those features, just as it would do for an explicitly 322 declared feature. </p> 323 324 <p>An application might require a feature but not declare it because: </p> 325 326 <ul> 327 <li>The application was compiled against an older version of the Android library 328 (Android 1.5 or earlier) and the <code><uses-feature></code> element was 329 not available.</li> 330 <li>The developer incorrectly assumed that the feature would be present on all 331 devices and a declaration was unnecessary.</li> 332 <li>The developer omitted the feature declaration accidentally.</li> 333 <li>The developer declared the feature explicitly, but the declaration was not 334 valid. For example, a spelling error in the <code><uses-feature></code> 335 element name or an unrecognized string value for the 336 <code>android:name</code> attribute would invalidate the feature declaration. 337 </li> 338 </ul> 339 340 <p>To account for the cases above, Android Market attempts to discover an 341 application's implied feature requirements by examining <em>other elements</em> 342 declared in the manifest file, specifically, 343 <code><uses-permission></code> elements.</p> 344 345 <p>If an application requests hardware-related permissions, Android Market 346 <em>assumes that the application uses the underlying hardware features and 347 therefore requires those features</em>, even though there might be no 348 corresponding to <code><uses-feature></code> declarations. For such 349 permissions, Android Market adds the underlying hardware features to the 350 metadata that it stores for the application and sets up filters for them.</p> 351 352 <p>For example, if an application requests the <code>CAMERA</code> permission 353 but does not declare a <code><uses-feature></code> element for 354 <code>android.hardware.camera</code>, Android Market considers that the 355 application requires a camera and should not be shown to users whose devices do 356 not offer a camera.</p> 357 358 <p>If you don't want Android Market to filter based on a specific implied 359 feature, you can disable that behavior. To do so, declare the feature explicitly 360 in a <code><uses-feature></code> element and include an 361 <code>android:required="false"</code> attribute. For example, to disable 362 filtering derived from the <code>CAMERA</code> permission, you would declare 363 the feature as shown below.</p> 364 365 <pre><uses-feature android:name="android.hardware.camera" android:required="false" /></pre> 366 367 <p class="caution">It's important to understand that the permissions that you 368 request in <code><uses-permission></code> elements can directly affect how 369 Android Market filters your application. The reference section <a 370 href="#permissions">Permissions that Imply Feature Requirements</a>, 371 below, lists the full set of permissions that imply feature requirements and 372 therefore trigger filtering.</p> 373 374 <h3 id="bt-permission-handling">Special handling for Bluetooth feature</h3> 375 376 <p>Android Market applies slightly different rules than described above, when 377 determining filtering for Bluetooth.</p> 378 379 <p>If an application declares a Bluetooth permission in a 380 <code><uses-permission></code> element, but does not explicitly declare 381 the Bluetooth feature in a <code><uses-feature></code> element, Android 382 Market checks the version(s) of the Android platform on which the application is 383 designed to run, as specified in the <code><uses-sdk></code> element. </p> 384 385 <p>As shown in the table below, Android Market enables filtering for the 386 Bluetooth feature only if the application declares its lowest or targeted 387 platform as Android 2.0 (API level 5) or higher. However, note that Android 388 market applies the normal rules for filtering when the application explicitly 389 declares the Bluetooth feature in a <code><uses-feature></code> element. 390 </p> 391 392 <p class="caption"><strong>Table 1.</strong> How Android Market determines the 393 Bluetooth feature requirement for an application that requests a Bluetooth 394 permission but does not declare the Bluetooth feature in a 395 <code><uses-feature></code> element.</p> 396 397 <table style="margin-top:1em;"> 398 <tr> 399 <th><nobr>If <code>minSdkVersion</code> is ...</nobr></th> 400 <th><nobr>or <code>targetSdkVersion</code> is</nobr></th> 401 <th>Result</th> 402 </tr> 403 <tr> 404 <td><nobr><=4 (or uses-sdk is not declared)</nobr></td> 405 <td><=4</td> 406 <td>Android Market <em>will not</em> filter the application from any devices 407 based on their reported support for the <code>android.hardware.bluetooth</code> 408 feature.</td> 409 </tr> 410 <tr> 411 <td><=4</td> 412 <td>>=5</td> 413 <td rowspan="2">Android Market filters the application from any devices that 414 do not support the <code>android.hardware.bluetooth</code> feature (including 415 older releases).</td> 416 </tr> 417 <tr> 418 <td>>=5</td> 419 <td>>=5</td> 420 </tr> 421 </table> 422 423 <p>The examples below illustrate the different filtering effects, based on how 424 Android Market handles the Bluetooth feature. </p> 425 426 <dl> 427 <dt>In first example, an application that is designed to run on older API levels 428 declares a Bluetooth permission, but does not declare the Bluetooth feature in a 429 <code><uses-feature></code> element.</dt> 430 <dd><em>Result:</em> Android Market does not filter the application from any device.</dd> 431 </dl> 432 433 <pre><manifest ...> 434 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> 435 <uses-sdk android:minSdkVersion="3" /> 436 ... 437 </manifest></pre> 438 439 <dl> 440 <dt>In the second example, below, the same application also declares a target 441 API level of "5". </dt> 442 <dd><em>Result:</em> Android Market now assumes that the feature is required and 443 will filter the application from all devices that do not report Bluetooth support, 444 including devices running older versions of the platform. </dd> 445 </dl> 446 447 <pre><manifest ...> 448 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> 449 <uses-sdk android:minSdkVersion="3" android:targetSdkVersion="5" /> 450 ... 451 </manifest></pre> 452 453 <dl> 454 <dt>Here the same application now specifically declares the Bluetooth feature.</dt> 455 <dd><em>Result:</em> Identical to the previous example (filtering is applied).</dd> 456 </dl> 457 458 <pre><manifest ...> 459 <uses-feature android:name="android.hardware.bluetooth" /> 460 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> 461 <uses-sdk android:minSdkVersion="3" android:targetSdkVersion="5" /> 462 ... 463 </manifest></pre> 464 465 <dl> 466 <dt>Finally, in the case below, the same application adds an 467 <code>android:required="false"</code> attribute.</dt> 468 <dd><em>Result:</em> Android Market disables filtering based on Bluetooth 469 feature support, for all devices.</dd> 470 </dl> 471 472 <pre><manifest ...> 473 <uses-feature android:name="android.hardware.bluetooth" android:required="false" /> 474 <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> 475 <uses-sdk android:minSdkVersion="3" android:targetSdkVersion="5" /> 476 ... 477 </manifest></pre> 478 479 480 481 <h3 id="testing">Testing the features required by your application</h3> 482 483 <p>You can use the <code>aapt</code> tool, included in the Android SDK, to 484 determine how Android Market will filter your application, based on its declared 485 features and permissions. To do so, run <code>aapt</code> with the <code>dump 486 badging</code> command. This causes <code>aapt</code> to parse your 487 application's manifest and apply the same rules as used by Android Market to 488 determine the features that your application requires. </p> 489 490 <p>To use the tool, follow these steps: </p> 491 492 <ol> 493 <li>First, build and export your application as an unsigned <code>.apk</code>. 494 If you are developing in Eclipse with ADT, right-click the project and select 495 <strong>Android Tools</strong> > <strong>Export Unsigned Application 496 Package</strong>. Select a destination filename and path and click 497 <strong>OK</strong>. </li> 498 <li>Next, locate the <code>aapt</code> tool, if it is not already in your PATH. 499 If you are using SDK Tools r8 or higher, you can find <code>aapt</code> in the 500 <code><<em>SDK</em>>/platform-tools/</code> directory. 501 <p class="note"><strong>Note:</strong> You must use the version of 502 <code>aapt</code> that is provided for the latest Platform-Tools component available. If 503 you do not have the latest Platform-Tools component, download it using the <a 504 href="{@docRoot}sdk/adding-components.html">Android SDK and AVD Manager</a>. 505 </p></li> 506 <li>Run <code>aapt</code> using this syntax: </li> 507 </ol> 508 509 <pre>$ aapt dump badging <<em>path_to_exported_.apk</em>></pre> 510 511 <p>Here's an example of the command output for the second Bluetooth example, above: </p> 512 513 <pre>$ ./aapt dump badging BTExample.apk 514 package: name='com.example.android.btexample' versionCode='' versionName='' 515 <strong>uses-permission:'android.permission.BLUETOOTH_ADMIN'</strong> 516 <strong>uses-feature:'android.hardware.bluetooth'</strong> 517 sdkVersion:'3' 518 targetSdkVersion:'5' 519 application: label='BT Example' icon='res/drawable/app_bt_ex.png' 520 launchable activity name='com.example.android.btexample.MyActivity'label='' icon='' 521 uses-feature:'android.hardware.touchscreen' 522 main 523 supports-screens: 'small' 'normal' 'large' 524 locales: '--_--' 525 densities: '160' 526 </pre> 527 528 529 <h2 id=features-reference>Features Reference</h2> 530 531 <p>The tables below provide reference information about hardware and software 532 features and the permissions that can imply them on Android Market. </p> 533 534 <h3 id="hw-features">Hardware features</h3> 535 536 <p>The table below describes the hardware feature descriptors supported by the 537 most current platform release. To signal that your application uses or requires 538 a hardware feature, declare each value in a <code>android:name</code> attribute 539 in a separate <code><uses-feature></code> element. </p> 540 541 <table> 542 <tr> 543 <th>Feature Type</th> 544 <th>Feature Descriptor</th> 545 <th style="min-width:170px">Description</th> 546 <th>Comments</th> 547 </tr> 548 <tr> 549 <td>Audio</td> 550 <td><code>android.hardware.audio.low_latency</td> 551 <td>The application uses a low-latency audio pipeline on the device and 552 is sensitive to delays or lag in sound input or output.</td> 553 <td> 554 </td> 555 </tr> 556 <tr> 557 <td>Bluetooth</td> 558 <td><code>android.hardware.bluetooth</td> 559 <td>The application uses Bluetooth radio features in the device.</td> 560 <td> 561 </td> 562 </tr> 563 <tr> 564 <td rowspan="4">Camera</td> 565 <td><code>android.hardware.camera</code></td> 566 <td>The application uses the device's camera. If the device supports 567 multiple cameras, the application uses the camera that facing 568 away from the screen.</td> 569 <td></td> 570 </tr> 571 <tr> 572 <td><code>android.hardware.camera.autofocus</code></td> 573 <td>Subfeature. The application uses the device camera's autofocus capability.</td> 574 <td rowspan="3">These subfeatures implicitly declare the 575 <code>android.hardware.camera</code> parent feature, unless declared with 576 <code>android:required="false"</code>.</td> 577 </tr> 578 <tr> 579 <td><code>android.hardware.camera.flash</code></td> 580 <td>Subfeature. The application uses the device camera's flash.</td> 581 </tr> 582 <tr> 583 <td><code>android.hardware.camera.front</code></td> 584 <td>Subfeature. The application uses a front-facing camera on the device.</td> 585 </tr> 586 587 <tr> 588 <td rowspan="3">Location</td> 589 <td><code>android.hardware.location</code></td> 590 <td>The application uses one or more features on the device for determining 591 location, such as GPS location, network location, or cell location.</td> 592 <td></td> 593 </tr> 594 <tr> 595 <td><code>android.hardware.location.network</code></td> 596 <td>Subfeature. The application uses coarse location coordinates obtained from 597 a network-based geolocation system supported on the device.</td> 598 <td rowspan="2">These subfeatures implicitly declare the 599 <code>android.hardware.location</code> parent feature, unless declared with 600 <code>android:required="false"</code>. </td> 601 </tr> 602 <tr> 603 <td><code>android.hardware.location.gps</code></td> 604 <td>Subfeature. The application uses precise location coordinates obtained 605 from a Global Positioning System receiver on the device. </td> 606 </tr> 607 <tr> 608 <td>Microphone</td> 609 <td><code>android.hardware.microphone</code></td> 610 <td>The application uses a microphone on the device. 611 </td> 612 <td></td> 613 </tr> 614 <tr> 615 <td>NFC</td> 616 <td><code>android.hardware.nfc</td> 617 <td>The application uses Near Field Communications radio features in the device.</td> 618 <td></td> 619 </tr> 620 <tr> 621 <td rowspan="6">Sensors</td> 622 <td><code>android.hardware.sensor.accelerometer</code></td> 623 <td>The application uses motion readings from an accelerometer on the 624 device.</td> 625 <td></td> 626 </tr> 627 <tr> 628 <td><code>android.hardware.sensor.barometer</code></td> 629 <td>The application uses the device's barometer.</td> 630 <td></td> 631 </tr> 632 <tr> 633 <td><code>android.hardware.sensor.compass</code></td> 634 <td>The application uses directional readings from a magnetometer (compass) on 635 the device.</td> 636 <td></td> 637 </tr> 638 <tr> 639 <td><code>android.hardware.sensor.gyroscope</code></td> 640 <td>The application uses the device's gyroscope sensor.</td> 641 <td></td> 642 </tr> 643 <tr> 644 <td><code>android.hardware.sensor.light</code></td> 645 <td>The application uses the device's light sensor.</td> 646 <td></td> 647 </tr> 648 <tr> 649 <td><code>android.hardware.sensor.proximity</code></td> 650 <td>The application uses the device's proximity sensor.</td> 651 <td></td> 652 </tr> 653 654 <tr> 655 <td rowspan="2">Screen</td> 656 <td><code>android.hardware.screen.landscape</code></td> 657 <td>The application requires landscape orientation.</td> 658 <td rowspan="2"> 659 <p>For example, if your app requires portrait orientation, you should declare 660 <code><uses-feature android:name="android.hardware.screen.portrait"/></code> so that only devices 661 that support portrait orientation (whether always or by user choice) can install your app. If your 662 application <em>supports</em> both orientations, then you don't need to declare either.</p> 663 <p>Both orientations are assumed <em>not required</em>, by default, so your app may be installed 664 on devices that support one or both orientations. However, if any of your activities request that 665 they run in a specific orientation, using the <a 666 href="{@docRoot}guide/topics/manifest/activity-element.html#screen">{@code 667 android:screenOrientation}</a> attribute, then this also declares that the application requires that 668 orientation. For example, if you declare <a 669 href="{@docRoot}guide/topics/manifest/activity-element.html#screen">{@code 670 android:screenOrientation}</a> with either {@code "landscape"}, {@code "reverseLandscape"}, or 671 {@code "sensorLandscape"}, then your application will be available only to devices that support 672 landscape orientation. As a best practice, you should still declare your requirement for this 673 orientation using a {@code <uses-feature>} element. If you declare an orientation for your 674 activity using <a href="{@docRoot}guide/topics/manifest/activity-element.html#screen">{@code 675 android:screenOrientation}</a>, but don't actually <em>require</em> it, you can disable the 676 requirement by declaring the orientation with a {@code <uses-feature>} element and include 677 {@code android:required="false"}.</p> 678 <p>For backwards compatibility, any device running a platform version that supports only API 679 level 12 or lower is assumed to support both landscape and portrait.</p> 680 </td> 681 </tr> 682 <tr> 683 <td><code>android.hardware.screen.portrait</code></td> 684 <td>The application requires portrait orientation.</td> 685 </tr> 686 687 <tr> 688 <td rowspan="3">Telephony</td> 689 <td><code>android.hardware.telephony</code></td> 690 <td>The application uses telephony features on the device, such as telephony 691 radio with data communication services.</td> 692 <td></td> 693 </tr> 694 <tr> 695 <td><code>android.hardware.telephony.cdma</code></td> 696 <td>Subfeature. The application uses CDMA telephony radio features on the 697 device. </td> 698 <td rowspan="2">These subfeatures implicitly declare the 699 <code>android.hardware.telephony</code> parent feature, unless declared with 700 <code>android:required="false"</code>. </td> 701 </tr> 702 <tr> 703 <td><code>android.hardware.telephony.gsm</code></td> 704 <td>Subfeature. The application uses GSM telephony radio features on the 705 device.</td> 706 </tr> 707 708 <tr> 709 <td rowspan="7">Touchscreen</td> 710 <td><code>android.hardware.faketouch</code></td> 711 <td>The application uses basic touch interaction events, such as "click down", "click 712 up", and drag.</td> 713 <td><p>When declared as required, this indicates that the application is compatible with a device 714 only if it offers an emulated touchscreen ("fake touch" interface), or better. A device that offers 715 a fake touch interface provides a user input system that emulates a subset of touchscreen 716 capabilities. For example, a mouse or remote control that drives an on-screen cursor provides a fake 717 touch interface. If your application requires basic point and click interaction (in other 718 words, it won't work with <em>only</em> a d-pad controller), you should declare this feature. 719 Because this is the minimum level of touch interaction, your app will also be compatible with 720 devices that offer more complex touch interfaces.</p> 721 <p class="note"><strong>Note:</strong> Because applications require the {@code 722 android.hardware.touchscreen} feature by default, if you want your application to be available to 723 devices that provide a fake touch interface, you must also explicitly declare that a touch screen is 724 <em>not</em> required by declaring {@code <uses-feature 725 android:name="android.hardware.touchscreen" <strong>android:required="false"</strong> 726 />}</p></td> 727 </tr> 728 729 <tr> 730 <td><code>android.hardware.faketouch.multitouch.distinct</code></td> 731 <td>The application performs distinct tracking of two or more "fingers" on a fake touch 732 interface. This is a superset of the faketouch feature.</td> 733 <td><p>When declared as required, this indicates that the application is compatible with a device 734 only if it supports touch emulation for events that supports distinct tracking of two or more 735 fingers, or better.</p> 736 <p>Unlike the distinct multitouch defined by {@code 737 android.hardware.touchscreen.multitouch.distinct}, input devices that support distinct multi-touch 738 with a fake touch interface will not support all two-finger gestures, because the input is 739 being transformed to cursor movement on the screen. That is, single finger gestures on such a device 740 move a cursor; two-finger swipes will result in single-finger touch events; other two-finger 741 gestures will result in the corresponding two-finger touch event. An example device that supports 742 distinct multi-touch with a fake touch interface is one that provides a trackpad for cursor movement 743 which also supports two or more fingers.</p></td> 744 </tr> 745 746 <tr> 747 <td><code>android.hardware.faketouch.multitouch.jazzhand</code></td> 748 <td>The application performs distinct tracking of five or more "fingers" on a fake touch 749 interface. This is a superset of the faketouch feature.</td> 750 <td><p>When declared as required, this indicates that the application is compatible with a device 751 only if it supports touch emulation for events that supports distinct tracking of five or more 752 fingers.</p> 753 <p>Unlike the distinct multitouch defined by {@code 754 android.hardware.touchscreen.multitouch.jazzhand}, input devices that support jazzhand multi-touch 755 with a fake touch interface will not support all five-finger gestures, because the input is being 756 transformed to cursor movement on the screen. That is, single finger gestures on such a device move 757 a cursor; multi-finger gestures will result in single-finger touch events; other multi-finger 758 gestures will result in the corresponding multi-finger touch event. An example device that supports 759 distinct multi-touch with a fake touch interface is one that provides a trackpad for cursor movement 760 which also supports five or more fingers.</p></td> 761 </tr> 762 763 <tr> 764 <td><code>android.hardware.touchscreen</code></td> 765 <td>The application uses touchscreen capabilities for gestures that are more interactive 766 than basic touch events, such as a fling. This is a superset of the basic faketouch feature.</td> 767 <td><p>By default, your application requires this. As such, your application is <em>not</em> 768 available to devices that provide only an emulated touch interface ("fake touch"), by default. If 769 you want your application available to devices that provide a fake touch interface (or even devices 770 that provide only a d-pad controller), you must explicitly declare that a touch screen is not 771 required, by declaring {@code android.hardware.touchscreen} with {@code android:required="false"}. 772 You should do so even if your application uses—but does not <em>require</em>—a real 773 touch screen interface.</p> 774 <p>If your application <em>does require</em> a touch interface (in order to perform touch 775 gestures such as a fling), then you don't need to do anything, because this is required by default. 776 However, it's best if you explicitly declare all features used by your application, so you should 777 still declare this if your app uses it.</p> 778 <p>If you require more complex touch interaction, such as multi-finger gestures, you 779 should declare the advanced touch screen features below.</p></td> 780 </tr> 781 <tr> 782 <td><code>android.hardware.touchscreen.multitouch</code></td> 783 <td>The application uses basic two-point multitouch capabilities on the device 784 screen, such as for pinch gestures, but does not need to track touches independently. This 785 is a superset of touchscreen feature.</td> 786 <td>This implicitly declares the <code>android.hardware.touchscreen</code> parent feature, unless 787 declared with <code>android:required="false"</code>. </td> 788 </tr> 789 <tr> 790 <td><code>android.hardware.touchscreen.multitouch.distinct</code></td> 791 <td>Subfeature. The application uses advanced multipoint multitouch 792 capabilities on the device screen, such as for tracking two or more points fully 793 independently. This is a superset of multitouch feature.</td> 794 <td rowspan="2">This implicitly declares the <code>android.hardware.touchscreen.multitouch</code> 795 parent feature, unless declared with <code>android:required="false"</code>. </td> 796 </tr> 797 <tr> 798 <td><code>android.hardware.touchscreen.multitouch.jazzhand</code></td> 799 <td>The application uses advanced multipoint multitouch 800 capabilities on the device screen, for tracking up to five points fully 801 independently. This is a superset of distinct multitouch feature.</td> 802 </tr> 803 804 <tr> 805 <td rowspan="2">USB</td> 806 <td><code>android.hardware.usb.host</code></td> 807 <td>The application uses USB host mode features (behaves as the host and connects to USB 808 devices).</td> 809 <td></td> 810 </tr> 811 812 <tr> 813 <td><code>android.hardware.usb.accessory</code></td> 814 <td>The application uses USB accessory features (behaves as the USB device and connects to USB 815 hosts).</td> 816 <td></td> 817 </tr> 818 819 <tr> 820 <td>Wifi</td> 821 <td><code>android.hardware.wifi</code></td> 822 <td>The application uses 802.11 networking (wifi) features on the device.</td> 823 <td></td> 824 </tr> 825 826 </table> 827 828 <h3 id="sw-features">Software features</h3> 829 830 <p>The table below describes the software feature descriptors supported by the 831 most current platform release. To signal that your application uses or requires 832 a software feature, declare each value in a <code>android:name</code> attribute 833 in a separate <code><uses-feature></code> element. </p> 834 835 836 <table> 837 <tr> 838 <th>Feature</th> 839 <th>Attribute Value</th> 840 <th>Description</th> 841 <th>Comments</th> 842 </tr> 843 <tr> 844 <td>Live Wallpaper</td> 845 <td><code>android.software.live_wallpaper</code></td> 846 <td>The application uses or provides Live Wallpapers.</td> 847 <td></td> 848 </tr> 849 <tr> 850 <td rowspan="2">SIP/VOIP</td> 851 <td><code>android.software.sip</code></td> 852 <td>The application uses SIP service on the device. 853 </td> 854 <td></td> 855 </tr> 856 <tr> 857 <td><code>android.software.sip.voip</code></td> 858 <td>Subfeature. The application uses SIP-based VOIP service on the device. 859 </td> 860 <td>This subfeature implicitly declares the <code>android.software.sip</code> parent feature, 861 unless declared with <code>android:required="false"</code>.</td> 862 </tr> 863 </table> 864 865 866 <h3 id="permissions">Permissions that Imply Feature Requirements</h3> 867 868 <p>Some feature constants listed in the tables above were made available to 869 applications <em>after</em> the corresponding API; for example, the 870 <code>android.hardware.bluetooth</code> feature was added in Android 2.2 (API 871 level 8), but the bluetooth API that it refers to was added in Android 2.0 (API 872 level 5). Because of this, some apps were able to use the API before they had 873 the ability to declare that they require the API via the 874 <code><uses-feature></code> system. </p> 875 876 <p>To prevent those apps from being made available unintentionally, Android 877 Market assumes that certain hardware-related permissions indicate that the 878 underlying hardware features are required by default. For instance, applications 879 that use Bluetooth must request the <code>BLUETOOTH</code> permission in a 880 <code><uses-permission></code> element — for legacy apps, Android 881 Market assumes that the permission declaration means that the underlying 882 <code>android.hardware.bluetooth</code> feature is required by the application 883 and sets up filtering based on that feature. </p> 884 885 <p>The table below lists permissions that imply feature requirements 886 equivalent to those declared in <code><uses-feature></code> elements. Note 887 that <code><uses-feature></code> declarations, including any declared 888 <code>android:required</code> attribute, always take precedence over features 889 implied by the permissions below. </p> 890 891 <p>For any of the permissions below, you can disable filtering based on the 892 implied feature by explicitly declaring the implied feature explicitly, in a 893 <code><uses-feature></code> element, with an 894 <code>android:required="false"</code> attribute. For example, to disable any 895 filtering based on the <code>CAMERA</code> permission, you would add this 896 <code><uses-feature></code> declaration to the manifest file:</p> 897 898 <pre><uses-feature android:name="android.hardware.camera" android:required="false" /></pre> 899 900 <table id="permissions-features" > 901 <tr> 902 <th>Category</th> 903 <th>This Permission...</th> 904 <th>Implies This Feature Requirement</th> 905 <!-- <th>Comments</th> --> 906 </tr> 907 908 909 <tr> 910 <td rowspan="2">Bluetooth</td> 911 <td><code>BLUETOOTH</code></td> 912 <td><code>android.hardware.bluetooth</code> 913 <p>(See <a href="#bt-permission-handling">Special handling for Bluetooth feature</a> for details.)</p></td> 914 <!-- <td></td> --> 915 </tr> 916 <tr> 917 <td><code>BLUETOOTH_ADMIN</code></td> 918 <td><code>android.hardware.bluetooth</code></td> 919 <!-- <td></td> --> 920 </tr> 921 922 <tr> 923 <td>Camera</td> 924 <td><code>CAMERA</code></td> 925 <td><code>android.hardware.camera</code> <em>and</em> 926 <br><code>android.hardware.camera.autofocus</code></td> 927 <!-- <td></td> --> 928 </tr> 929 930 <tr> 931 <td rowspan="5">Location</td> 932 <td><code>ACCESS_MOCK_LOCATION</code></td> 933 <td><code>android.hardware.location</code></td> 934 <!-- <td></td> --> 935 </tr> 936 <tr> 937 <td><code>ACCESS_LOCATION_EXTRA_COMMANDS</code></td> 938 <td><code>android.hardware.location</code></td> 939 <!-- <td></td> --> 940 </tr> 941 <tr> 942 <td><code>INSTALL_LOCATION_PROVIDER</code></td> 943 <td><code>android.hardware.location</code></td> 944 <!-- <td></td> --> 945 </tr> 946 <tr> 947 <td><code>ACCESS_COARSE_LOCATION</code></td> 948 <td><code>android.hardware.location.network</code> <em>and</em> 949 <br><code>android.hardware.location</code></td> 950 <!-- <td></td> --> 951 </tr> 952 <tr> 953 <td><code>ACCESS_FINE_LOCATION</code></td> 954 <td><code>android.hardware.location.gps</code> <em>and</em> 955 <br><code>android.hardware.location</code></td> 956 <!-- <td></td> --> 957 </tr> 958 959 <tr> 960 <td>Microphone</td> 961 <td><code>RECORD_AUDIO</code></td> 962 <td><code>android.hardware.microphone</code></td> 963 <!-- <td></td> --> 964 </tr> 965 966 <tr> 967 <td rowspan="11">Telephony</td> 968 <td><code>CALL_PHONE</code></td> 969 <td><code>android.hardware.telephony</code></td> 970 <!-- <td></td> --> 971 </tr> 972 <tr> 973 <td><code>CALL_PRIVILEGED</code></td> 974 <td><code>android.hardware.telephony</code></td> 975 <!-- <td></td> --> 976 </tr> 977 978 <tr> 979 <td><code>MODIFY_PHONE_STATE</code></td> 980 <td><code>android.hardware.telephony</code></td> 981 <!-- <td></td> --> 982 </tr> 983 <tr> 984 <td><code>PROCESS_OUTGOING_CALLS</code></td> 985 <td><code>android.hardware.telephony</code></td> 986 <!-- <td></td> --> 987 </tr> 988 <tr> 989 <td><code>READ_SMS</code></td> 990 <td><code>android.hardware.telephony</code></td> 991 <!-- <td></td> --> 992 </tr> 993 <tr> 994 <td><code>RECEIVE_SMS</code></td> 995 <td><code>android.hardware.telephony</code></td> 996 <!-- <td></td> --> 997 </tr> 998 <tr> 999 <td><code>RECEIVE_MMS</code></td> 1000 <td><code>android.hardware.telephony</code></td> 1001 <!-- <td></td> --> 1002 </tr> 1003 <tr> 1004 <td><code>RECEIVE_WAP_PUSH</code></td> 1005 <td><code>android.hardware.telephony</code></td> 1006 <!-- <td></td> --> 1007 </tr> 1008 <tr> 1009 <td><code>SEND_SMS</code></td> 1010 <td><code>android.hardware.telephony</code></td> 1011 <!-- <td></td> --> 1012 </tr> 1013 <tr> 1014 <td><code>WRITE_APN_SETTINGS</code></td> 1015 <td><code>android.hardware.telephony</code></td> 1016 <!-- <td></td> --> 1017 </tr> 1018 <tr> 1019 <td><code>WRITE_SMS</code></td> 1020 <td><code>android.hardware.telephony</code></td> 1021 <!-- <td></td> --> 1022 </tr> 1023 1024 <tr> 1025 <td rowspan="3">Wifi</td> 1026 <td><code>ACCESS_WIFI_STATE</code></td> 1027 <td><code>android.hardware.wifi</code></td> 1028 <!-- <td></td> --> 1029 </tr> 1030 <tr> 1031 <td><code>CHANGE_WIFI_STATE</code></td> 1032 <td><code>android.hardware.wifi</code></td> 1033 <!-- <td></td> --> 1034 </tr> 1035 <tr> 1036 <td><code>CHANGE_WIFI_MULTICAST_STATE</code></td> 1037 <td><code>android.hardware.wifi</code></td> 1038 <!-- <td></td> --> 1039 </tr> 1040 </table>