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 page.title=Building and Running from the Command Line
 parent.title=Building and Running
 parent.link=index.html
 @jd:body

  <div id="qv-wrapper">
     <div id="qv">
       <h2>In this document</h2>
       <ol>
         <li><a href="#DebugMode">Building in Debug Mode</a></li>
         <li><a href="#ReleaseMode">Building in Release Mode</a>
           <ol>
             <li><a href="#ManualReleaseMode">Build unsigned</a></li>
             <li><a href="#AutoReleaseMode">Build signed and aligned</a></li>
             <li><a href="#OnceBuilt">Once built and signed in release mode</a></li>
           </ol>
         </li>
         <li><a href="#RunningOnEmulator">Running on the Emulator</a></li>
         <li><a href="#RunningOnDevice">Running on a Device</a></li>
         <li><a href="#Signing">Application Signing</a></li>
         <li><a href="#PluginReference">Plugin Language Reference</a></li>
       </ol>
   <h2>See also</h2>
   <ol>
     <li><a href="{@docRoot}sdk/installing/studio-build.html">
       Build System</a></li>
     <li><a href="{@docRoot}tools/devices/managing-avds-cmdline.html">
       Managing AVDs from the Command Line</a></li>
     <li><a href="{@docRoot}tools/devices/emulator.html">
       Using the Android Emulator</a></li>
     <li><a href="{@docRoot}tools/publishing/app-signing.html">
       Signing Your Applications</a></li>
   </ol>
     </div>
   </div>

   <p>By default, there are two build types to build your application using the Gradle build settings:
   one for debugging your application &mdash; <em>debug</em> &mdash; and one for building your
   final package for release &mdash; <em>release mode</em>. Regardless of which build type
   your modules use, the app must be signed before it can install on an emulator or device&mdash;with
   a debug key when building in debug mode and with your own private key when building in release mode.</p>

   <p>Whether you're building with the debug or release build type, you need to run
   and build your module. This will create the .apk file that you can install on an emulator or device.
   When you build using the debug build type, the .apk file is automatically signed by the SDK tools
   with a debug key based on the <code>debuggable true</code> setting in the module's build.gradle file,
   so it's instantly ready for installation onto an emulator or attached
   development device. You cannot distribute an application that is signed with a debug key.
   When you build using the release build type, the .apk file is <em>unsigned</em>, so you
   must manually sign it with your own private key, using Keytool and Jarsigner settings in the
   module's <code>build.gradle</code> file.</p>

   <p>It's important that you read and understand <a href=
   "{@docRoot}tools/publishing/app-signing.html">Signing Your Applications</a>, particularly once
   you're ready to release your application and share it with end-users. That document describes the
   procedure for generating a private key and then using it to sign your APK file. If you're just
   getting started, however, you can quickly run your applications on an emulator or your own
   development device by building in debug mode.</p>

   <p>If you don't have <a href="http://www.gradle.org/">Gradle</a>, you can obtain it from the <a href="http://gradle.org/">Gradle
   home page</a>. Install it and make sure it is in your executable PATH. Before calling Gradle, you
   need to declare the JAVA_HOME environment variable to specify the path to where the JDK is
   installed.</p>

   <p class="note"><strong>Note:</strong> When using <code>ant</code> and installing JDK on Windows,
   the default is to install in the "Program Files" directory. This location will cause
   <code>ant</code> to fail, because of the space. To fix the problem, you can specify the JAVA_HOME
   variable like this:
   <pre>set JAVA_HOME=c:\Progra~1\Java\&lt;jdkdir&gt;</pre>

   <p>The easiest solution, however, is to install JDK in a non-space directory, for example:</p>

   <pre>c:\java\jdk1.7</pre>

   <h2 id="DebugMode">Building in Debug Mode</h2>

   <p>For immediate application testing and debugging, you can build your application in debug mode
   and immediately install it on an emulator. In debug mode, the build tools automatically sign your
   application with a debug key and optimize the package with {@code zipalign}.</p>

   <p>To build in debug mode, open a command-line and navigate to the root of your project directory.
   Use Gradle to build your project in debug mode, invoke the <code>assembleDebug</code> build task
   using the Gradle wrapper script (<code>gradlew assembleRelease</code>).

   <p>This creates your debug <code>.apk</code> file inside the module <code>build/</code>
   directory, named <code>&lt;your_module_name&gt;-debug.apk</code>. The file is already signed
   with the debug key and has been aligned with
   <a href="{@docRoot}tools/help/zipalign.html"><code>zipalign</code></a>. </p>

   <p>On Windows platforms, type this command:</p>

 <pre>
 > gradlew.bat assembleDebug
 </pre>

 <p>On Mac OS and Linux platforms, type these commands:</p>

 <pre>
 $ chmod +x gradlew
 $ ./gradlew assembleDebug
 </pre>

   <p>The first command (<code>chmod</code>) adds the execution permission to the Gradle wrapper
   script and is only necessary the first time you build this project from the command line.</p>

   <p>After you build the project, the output APK for the app module is located in
   <code>app/build/outputs/apk/</code>, and the output AAR for any lib modules is located in
   <code>lib/build/outputs/libs/</code>.</p>

   <p>To see a list of all available build tasks for your project, type this command:</p>

 <pre>
 $ ./gradlew tasks
 </pre>

   <p>Each time you change a source file or resource, you must run Gradle again in order to package up
   the latest version of the application.</p>

   <p>To install and run your application on an emulator, see the section about <a href=
   "{@docRoot}tools/building/building-studio.html">Running on the Emulator</a>.</p>

   <h2 id="ReleaseMode">Building in Release Mode</h2>

   <p>When you're ready to release and distribute your application to end-users, you must build your
   application in release mode. Once you have built in release mode, it's a good idea to perform
   additional testing and debugging with the final .apk.</p>

   <p>Before you start building your application in release mode, be aware that you must sign the
   resulting application package with your private key, and should then align it using the {@code
   zipalign} tool. There are two approaches to building in release mode: build an unsigned package
   in release mode and then manually sign and align the package, or allow the build script to sign
   and align the package for you.</p>

   <h3 id="ManualReleaseMode">Build unsigned</h3>

   <p>If you build your application <em>unsigned</em>, then you will need to manually sign and align
   the package.</p>

   <p>To build an <em>unsigned</em> .apk in release mode, open a command-line and navigate to the
   root of your module directory. Invoke the <code>assembleRelease</code> build task.</li>

   <p>On Windows platforms, type this command:</p>

 <pre>
 > gradlew.bat assembleRelease
 </pre>

 <p>On Mac OS and Linux platforms, type this command:</p>

 <pre>
 $ ./gradlew assembleRelease
 </pre>


   <p>This creates your Android application .apk file inside the project <code>bin/</code>
   directory, named <code><em>&lt;your_module_name&gt;</em>-unsigned.apk</code>.</p>

   <p class="note"><strong>Note:</strong> The .apk file is <em>unsigned</em> at this point and can't
   be installed until signed with your private key.</p>

   <p>Once you have created the unsigned .apk, your next step is to sign the .apk with your private
   key and then align it with {@code zipalign}. To complete this procedure, read <a href=
   "{@docRoot}tools/publishing/app-signing.html">Signing Your Applications</a>.</p>

   <p>When your <code>.apk</code> has been signed and aligned, it's ready to be distributed to end-users.
   You should test the final build on different devices or AVDs to ensure that it
   runs properly on different platforms.</p>

   <h3 id="AutoReleaseMode">Build signed and aligned</h3>

   <p>If you would like, you can configure the Android build script to automatically sign and align
   your application package. To do so, you must provide the path to your keystore and the name of
   your key alias in your modules's build.gradle file. With this information provided,
   the build will prompt you for your keystore and alias password when you build using the release
   build type and produce your final application package, which will be ready for distribution.</p>

   <p>To specify your keystore and alias, open the module build.gradle file (found in
   the root of the module directory) and add entries for {@code storeFile}, {@code storePassword},
   {@code keyAlias} and {@code keyPassword}.
   For example:</p>
   <pre>
 storeFile file("myreleasekey.keystore")
 keyAlias "MyReleaseKey"
 </pre>

   <p>Save your changes. Now you can build a <em>signed</em> .apk in release mode:</p>

   <ol>
     <li>Open a command-line and navigate to the root of your module directory.</li>

     <li>Edit the build.gradle file to build your project in release mode:
       <p><pre>
 ...
 android {
     ...
     defaultConfig { ... }
     signingConfigs {
         release {
             storeFile file("myreleasekey.keystore")
             storePassword "password"
             keyAlias "MyReleaseKey"
             keyPassword "password"
         }
     }
     buildTypes {
         release {
             ...
             signingConfig signingConfigs.release
         }
     }
 }
 ...
 </pre></p>
     </li>

     <li>When prompted, enter you keystore and alias passwords.

       <p class="caution"><strong>Caution:</strong> As described above, your password will be
       visible on the screen.</p>
     </li>
   </ol>

   <p>This creates your Android application .apk file inside the module <code>build/</code>
   directory, named <code><em>&lt;your_module_name&gt;</em>-release.apk</code>. This .apk file has
   been signed with the private key specified in build.gradle file and aligned with {@code
   zipalign}. It's ready for installation and distribution.</p>

   <h3 id="OnceBuilt">Once built and signed in release mode</h3>

   <p>Once you have signed your application with a private key, you can install and run it on an
   <a href="#RunningOnEmulator">emulator</a> or <a href="#RunningOnDevice">device</a>. You can
   also try installing it onto a device from a web server. Simply upload the signed .apk to a web
   site, then load the .apk URL in your Android web browser to download the application and begin
   installation. (On your device, be sure you have enabled
   <em>Settings &gt; Applications &gt; Unknown sources</em>.)</p>

   <h2 id="RunningOnEmulator">Running on the Emulator</h2>

   <p>Before you can run your application on the Android Emulator, you must <a href=
   "{@docRoot}tools/devices/managing-avds.html">create an AVD</a>.</p>

   <p>To run your application:</p>

   <ol>
     <li>
       <strong>Open the AVD Manager and launch a virtual device</strong>

       <p>From your SDK's <code>platform-tools/</code> directory, execute the {@code android} tool
 with the <code>avd</code> options:</p>
       <pre>
 android avd
 </pre>

       <p>In the <em>Virtual Devices</em> view, select an AVD and click <strong>Start</strong>.</p>
     </li>

     <li>
       <strong>Install your application</strong>

       <p>From your SDK's <code>tools/</code> directory, install the {@code .apk} on the
       emulator:</p>
       <pre>
 adb install <em>&lt;path_to_your_bin&gt;</em>.apk
 </pre>

       <p>Your .apk file (signed with either a release or debug key) is in your module {@code build/}
       directory after you build your application.</p>

       <p>If there is more than one emulator running, you must specify the emulator upon which to
       install the application, by its serial number, with the <code>-s</code> option. For
       example:</p>
       <pre>
 adb -s emulator-5554 install <em>path/to/your/app</em>.apk
 </pre>

       <p>To see a list of available device serial numbers, execute {@code adb devices}.</p>
     </li>
   </ol>

   <p>If you don't see your application on the emulator, try closing the emulator and launching the
   virtual device again from the AVD Manager. Sometimes when you install an application for the
   first time, it won't show up in the application launcher or be accessible by other applications.
   This is because the package manager usually examines manifests completely only on emulator
   startup.</p>

   <p>Be certain to create multiple AVDs upon which to test your application. You should have one
   AVD for each platform and screen type with which your application is compatible. For instance, if
   your application compiles against the Android 4.0 (API Level 14) platform, you should create an
   AVD for each platform equal to and greater than 4.0 and an AVD for each <a href=
   "{@docRoot}guide/practices/screens_support.html">screen type</a> you support, then test your
   application on each one.</p>

   <p class="note"><strong>Tip:</strong> If you have <em>only one</em> emulator running, you can
   build your application and install it on the emulator in one simple step. Navigate to the root of
   your project directory and use Ant to compile the project with <em>install mode</em>: <code>ant
   install</code>. This will build your application, sign it with the debug key, and install it on
   the currently running emulator.</p>

   <h2 id="RunningOnDevice">Running on a Device</h2>

   <p>Before you can run your application on a device, you must perform some basic setup for your
   device:</p>

   <ul>
     <li>Enable <strong>USB debugging</strong> on your device.
       <ul>
         <li>On most devices running Android 3.2 or older, you can find the option under
           <strong>Settings > Applications > Development</strong>.</li>
         <li>On Android 4.0 and newer, it's in <strong>Settings > Developer options</strong>.
           <p class="note"><strong>Note:</strong> On Android 4.2 and newer, <strong>Developer
           options</strong> is hidden by default. To make it available, go
           to <strong>Settings > About phone</strong> and tap <strong>Build number</strong>
           seven times. Return to the previous screen to find <strong>Developer options</strong>.</p>
         </li>
       </ul>
     </li>

     <li>Ensure that your development computer can detect your device when connected via USB</li>
   </ul>

   <p>Read <a href="{@docRoot}tools/device.html#setting-up">Setting up a Device for
   Development</a> for more information.</p>

   <p>Once your device is set up and connected via USB, navigate to your SDK's <code>platform-tools/</code>
   directory and install the <code>.apk</code> on the device:</p>
   <pre>
 adb -d install <em>path/to/your/app</em>.apk
 </pre>

   <p>The {@code -d} flag specifies that you want to use the attached device (in case you also have
   an emulator running).</p>

   <p>For more information on the tools used above, please see the following documents:</p>

   <ul>
     <li><a href="{@docRoot}tools/help/android.html">android Tool</a></li>

     <li><a href="{@docRoot}tools/devices/emulator.html">Android Emulator</a></li>

     <li><a href="{@docRoot}tools/help/adb.html">Android Debug Bridge</a> (ADB)</li>
   </ul>

   <h2 id="Signing">Application Signing</h2>

   <p>As you begin developing Android applications, understand that all Android applications must be
   digitally signed before the system will install them on an emulator or device. There are two ways
   to do this: with a <em>debug key</em> (for immediate testing on an emulator or development
   device) or with a <em>private key</em> (for application distribution).</p>

   <p>The Android build tools help you get started by automatically signing your .apk files with a
   debug key at build time. This means that you can build your application and install it on the
   emulator without having to generate your own private key. However, please note that if you intend
   to publish your application, you <strong>must</strong> sign the application with your own private
   key, rather than the debug key generated by the SDK tools.</p>

   <p>Please read <a href="{@docRoot}tools/publishing/app-signing.html">Signing Your
   Applications</a>, which provides a thorough guide to application signing on Android and what it
   means to you as an Android application developer. The document also includes a guide to publishing
   and signing your application.</p>

  <h2 id="PluginReference">Android Plugin for Gradle</h2>

  <p>The Android build system uses the Android plugin for Gradle to support the Gradle Domain
  Specific Language (DSL) and declarative language elements. See the
  <a href="{@docRoot}tools/building/plugin-for-gradle.html">Android Plug-in for Gradle</a> section for
  a description of the plugin and a link to the complete list of the supported Gradle DSL elements.</p>
	page.title=Building and Running from the Command Line
	parent.title=Building and Running
	parent.link=index.html
	@jd:body

	<div id="qv-wrapper">
	<div id="qv">
	<h2>In this document</h2>
	<ol>
	<li><a href="#DebugMode">Building in Debug Mode</a></li>
	<li><a href="#ReleaseMode">Building in Release Mode</a>
	<ol>
	<li><a href="#ManualReleaseMode">Build unsigned</a></li>
	<li><a href="#AutoReleaseMode">Build signed and aligned</a></li>
	<li><a href="#OnceBuilt">Once built and signed in release mode</a></li>
	</ol>
	</li>
	<li><a href="#RunningOnEmulator">Running on the Emulator</a></li>
	<li><a href="#RunningOnDevice">Running on a Device</a></li>
	<li><a href="#Signing">Application Signing</a></li>
	<li><a href="#PluginReference">Plugin Language Reference</a></li>
	</ol>
	<h2>See also</h2>
	<ol>
	<li><a href="{@docRoot}sdk/installing/studio-build.html">
	Build System</a></li>
	<li><a href="{@docRoot}tools/devices/managing-avds-cmdline.html">
	Managing AVDs from the Command Line</a></li>
	<li><a href="{@docRoot}tools/devices/emulator.html">
	Using the Android Emulator</a></li>
	<li><a href="{@docRoot}tools/publishing/app-signing.html">
	Signing Your Applications</a></li>
	</ol>
	</div>
	</div>

	<p>By default, there are two build types to build your application using the Gradle build settings:
	one for debugging your application — <em>debug</em> — and one for building your
	final package for release — <em>release mode</em>. Regardless of which build type
	your modules use, the app must be signed before it can install on an emulator or device—with
	a debug key when building in debug mode and with your own private key when building in release mode.</p>

	<p>Whether you're building with the debug or release build type, you need to run
	and build your module. This will create the .apk file that you can install on an emulator or device.
	When you build using the debug build type, the .apk file is automatically signed by the SDK tools
	with a debug key based on the <code>debuggable true</code> setting in the module's build.gradle file,
	so it's instantly ready for installation onto an emulator or attached
	development device. You cannot distribute an application that is signed with a debug key.
	When you build using the release build type, the .apk file is <em>unsigned</em>, so you
	must manually sign it with your own private key, using Keytool and Jarsigner settings in the
	module's <code>build.gradle</code> file.</p>

	<p>It's important that you read and understand <a href=
	"{@docRoot}tools/publishing/app-signing.html">Signing Your Applications</a>, particularly once
	you're ready to release your application and share it with end-users. That document describes the
	procedure for generating a private key and then using it to sign your APK file. If you're just
	getting started, however, you can quickly run your applications on an emulator or your own
	development device by building in debug mode.</p>

	<p>If you don't have <a href="http://www.gradle.org/">Gradle</a>, you can obtain it from the <a href="http://gradle.org/">Gradle
	home page</a>. Install it and make sure it is in your executable PATH. Before calling Gradle, you
	need to declare the JAVA_HOME environment variable to specify the path to where the JDK is
	installed.</p>

	<p class="note"><strong>Note:</strong> When using <code>ant</code> and installing JDK on Windows,
	the default is to install in the "Program Files" directory. This location will cause
	<code>ant</code> to fail, because of the space. To fix the problem, you can specify the JAVA_HOME
	variable like this:
	<pre>set JAVA_HOME=c:\Progra~1\Java\<jdkdir></pre>

	<p>The easiest solution, however, is to install JDK in a non-space directory, for example:</p>

	<pre>c:\java\jdk1.7</pre>

	<h2 id="DebugMode">Building in Debug Mode</h2>

	<p>For immediate application testing and debugging, you can build your application in debug mode
	and immediately install it on an emulator. In debug mode, the build tools automatically sign your
	application with a debug key and optimize the package with {@code zipalign}.</p>

	<p>To build in debug mode, open a command-line and navigate to the root of your project directory.
	Use Gradle to build your project in debug mode, invoke the <code>assembleDebug</code> build task
	using the Gradle wrapper script (<code>gradlew assembleRelease</code>).

	<p>This creates your debug <code>.apk</code> file inside the module <code>build/</code>
	directory, named <code><your_module_name>-debug.apk</code>. The file is already signed
	with the debug key and has been aligned with
	<a href="{@docRoot}tools/help/zipalign.html"><code>zipalign</code></a>. </p>

	<p>On Windows platforms, type this command:</p>

	<pre>
	> gradlew.bat assembleDebug
	</pre>

	<p>On Mac OS and Linux platforms, type these commands:</p>

	<pre>
	$ chmod +x gradlew
	$ ./gradlew assembleDebug
	</pre>

	<p>The first command (<code>chmod</code>) adds the execution permission to the Gradle wrapper
	script and is only necessary the first time you build this project from the command line.</p>

	<p>After you build the project, the output APK for the app module is located in
	<code>app/build/outputs/apk/</code>, and the output AAR for any lib modules is located in
	<code>lib/build/outputs/libs/</code>.</p>

	<p>To see a list of all available build tasks for your project, type this command:</p>

	<pre>
	$ ./gradlew tasks
	</pre>

	<p>Each time you change a source file or resource, you must run Gradle again in order to package up
	the latest version of the application.</p>

	<p>To install and run your application on an emulator, see the section about <a href=
	"{@docRoot}tools/building/building-studio.html">Running on the Emulator</a>.</p>

	<h2 id="ReleaseMode">Building in Release Mode</h2>

	<p>When you're ready to release and distribute your application to end-users, you must build your
	application in release mode. Once you have built in release mode, it's a good idea to perform
	additional testing and debugging with the final .apk.</p>

	<p>Before you start building your application in release mode, be aware that you must sign the
	resulting application package with your private key, and should then align it using the {@code
	zipalign} tool. There are two approaches to building in release mode: build an unsigned package
	in release mode and then manually sign and align the package, or allow the build script to sign
	and align the package for you.</p>

	<h3 id="ManualReleaseMode">Build unsigned</h3>

	<p>If you build your application <em>unsigned</em>, then you will need to manually sign and align
	the package.</p>

	<p>To build an <em>unsigned</em> .apk in release mode, open a command-line and navigate to the
	root of your module directory. Invoke the <code>assembleRelease</code> build task.</li>

	<p>On Windows platforms, type this command:</p>

	<pre>
	> gradlew.bat assembleRelease
	</pre>

	<p>On Mac OS and Linux platforms, type this command:</p>

	<pre>
	$ ./gradlew assembleRelease
	</pre>


	<p>This creates your Android application .apk file inside the project <code>bin/</code>
	directory, named <code><em><your_module_name></em>-unsigned.apk</code>.</p>

	<p class="note"><strong>Note:</strong> The .apk file is <em>unsigned</em> at this point and can't
	be installed until signed with your private key.</p>

	<p>Once you have created the unsigned .apk, your next step is to sign the .apk with your private
	key and then align it with {@code zipalign}. To complete this procedure, read <a href=
	"{@docRoot}tools/publishing/app-signing.html">Signing Your Applications</a>.</p>

	<p>When your <code>.apk</code> has been signed and aligned, it's ready to be distributed to end-users.
	You should test the final build on different devices or AVDs to ensure that it
	runs properly on different platforms.</p>

	<h3 id="AutoReleaseMode">Build signed and aligned</h3>

	<p>If you would like, you can configure the Android build script to automatically sign and align
	your application package. To do so, you must provide the path to your keystore and the name of
	your key alias in your modules's build.gradle file. With this information provided,
	the build will prompt you for your keystore and alias password when you build using the release
	build type and produce your final application package, which will be ready for distribution.</p>

	<p>To specify your keystore and alias, open the module build.gradle file (found in
	the root of the module directory) and add entries for {@code storeFile}, {@code storePassword},
	{@code keyAlias} and {@code keyPassword}.
	For example:</p>
	<pre>
	storeFile file("myreleasekey.keystore")
	keyAlias "MyReleaseKey"
	</pre>

	<p>Save your changes. Now you can build a <em>signed</em> .apk in release mode:</p>

	<ol>
	<li>Open a command-line and navigate to the root of your module directory.</li>

	<li>Edit the build.gradle file to build your project in release mode:
	<p><pre>
	...
	android {
	...
	defaultConfig { ... }
	signingConfigs {
	release {
	storeFile file("myreleasekey.keystore")
	storePassword "password"
	keyAlias "MyReleaseKey"
	keyPassword "password"
	}
	}
	buildTypes {
	release {
	...
	signingConfig signingConfigs.release
	}
	}
	}
	...
	</pre></p>
	</li>

	<li>When prompted, enter you keystore and alias passwords.

	<p class="caution"><strong>Caution:</strong> As described above, your password will be
	visible on the screen.</p>
	</li>
	</ol>

	<p>This creates your Android application .apk file inside the module <code>build/</code>
	directory, named <code><em><your_module_name></em>-release.apk</code>. This .apk file has
	been signed with the private key specified in build.gradle file and aligned with {@code
	zipalign}. It's ready for installation and distribution.</p>

	<h3 id="OnceBuilt">Once built and signed in release mode</h3>

	<p>Once you have signed your application with a private key, you can install and run it on an
	<a href="#RunningOnEmulator">emulator</a> or <a href="#RunningOnDevice">device</a>. You can
	also try installing it onto a device from a web server. Simply upload the signed .apk to a web
	site, then load the .apk URL in your Android web browser to download the application and begin
	installation. (On your device, be sure you have enabled
	<em>Settings > Applications > Unknown sources</em>.)</p>

	<h2 id="RunningOnEmulator">Running on the Emulator</h2>

	<p>Before you can run your application on the Android Emulator, you must <a href=
	"{@docRoot}tools/devices/managing-avds.html">create an AVD</a>.</p>

	<p>To run your application:</p>

	<ol>
	<li>
	<strong>Open the AVD Manager and launch a virtual device</strong>

	<p>From your SDK's <code>platform-tools/</code> directory, execute the {@code android} tool
	with the <code>avd</code> options:</p>
	<pre>
	android avd
	</pre>

	<p>In the <em>Virtual Devices</em> view, select an AVD and click <strong>Start</strong>.</p>
	</li>

	<li>
	<strong>Install your application</strong>

	<p>From your SDK's <code>tools/</code> directory, install the {@code .apk} on the
	emulator:</p>
	<pre>
	adb install <em><path_to_your_bin></em>.apk
	</pre>

	<p>Your .apk file (signed with either a release or debug key) is in your module {@code build/}
	directory after you build your application.</p>

	<p>If there is more than one emulator running, you must specify the emulator upon which to
	install the application, by its serial number, with the <code>-s</code> option. For
	example:</p>
	<pre>
	adb -s emulator-5554 install <em>path/to/your/app</em>.apk
	</pre>

	<p>To see a list of available device serial numbers, execute {@code adb devices}.</p>
	</li>
	</ol>

	<p>If you don't see your application on the emulator, try closing the emulator and launching the
	virtual device again from the AVD Manager. Sometimes when you install an application for the
	first time, it won't show up in the application launcher or be accessible by other applications.
	This is because the package manager usually examines manifests completely only on emulator
	startup.</p>

	<p>Be certain to create multiple AVDs upon which to test your application. You should have one
	AVD for each platform and screen type with which your application is compatible. For instance, if
	your application compiles against the Android 4.0 (API Level 14) platform, you should create an
	AVD for each platform equal to and greater than 4.0 and an AVD for each <a href=
	"{@docRoot}guide/practices/screens_support.html">screen type</a> you support, then test your
	application on each one.</p>

	<p class="note"><strong>Tip:</strong> If you have <em>only one</em> emulator running, you can
	build your application and install it on the emulator in one simple step. Navigate to the root of
	your project directory and use Ant to compile the project with <em>install mode</em>: <code>ant
	install</code>. This will build your application, sign it with the debug key, and install it on
	the currently running emulator.</p>

	<h2 id="RunningOnDevice">Running on a Device</h2>

	<p>Before you can run your application on a device, you must perform some basic setup for your
	device:</p>

	<ul>
	<li>Enable <strong>USB debugging</strong> on your device.
	<ul>
	<li>On most devices running Android 3.2 or older, you can find the option under
	<strong>Settings > Applications > Development</strong>.</li>
	<li>On Android 4.0 and newer, it's in <strong>Settings > Developer options</strong>.
	<p class="note"><strong>Note:</strong> On Android 4.2 and newer, <strong>Developer
	options</strong> is hidden by default. To make it available, go
	to <strong>Settings > About phone</strong> and tap <strong>Build number</strong>
	seven times. Return to the previous screen to find <strong>Developer options</strong>.</p>
	</li>
	</ul>
	</li>

	<li>Ensure that your development computer can detect your device when connected via USB</li>
	</ul>

	<p>Read <a href="{@docRoot}tools/device.html#setting-up">Setting up a Device for
	Development</a> for more information.</p>

	<p>Once your device is set up and connected via USB, navigate to your SDK's <code>platform-tools/</code>
	directory and install the <code>.apk</code> on the device:</p>
	<pre>
	adb -d install <em>path/to/your/app</em>.apk
	</pre>

	<p>The {@code -d} flag specifies that you want to use the attached device (in case you also have
	an emulator running).</p>

	<p>For more information on the tools used above, please see the following documents:</p>

	<ul>
	<li><a href="{@docRoot}tools/help/android.html">android Tool</a></li>

	<li><a href="{@docRoot}tools/devices/emulator.html">Android Emulator</a></li>

	<li><a href="{@docRoot}tools/help/adb.html">Android Debug Bridge</a> (ADB)</li>
	</ul>

	<h2 id="Signing">Application Signing</h2>

	<p>As you begin developing Android applications, understand that all Android applications must be
	digitally signed before the system will install them on an emulator or device. There are two ways
	to do this: with a <em>debug key</em> (for immediate testing on an emulator or development
	device) or with a <em>private key</em> (for application distribution).</p>

	<p>The Android build tools help you get started by automatically signing your .apk files with a
	debug key at build time. This means that you can build your application and install it on the
	emulator without having to generate your own private key. However, please note that if you intend
	to publish your application, you <strong>must</strong> sign the application with your own private
	key, rather than the debug key generated by the SDK tools.</p>

	<p>Please read <a href="{@docRoot}tools/publishing/app-signing.html">Signing Your
	Applications</a>, which provides a thorough guide to application signing on Android and what it
	means to you as an Android application developer. The document also includes a guide to publishing
	and signing your application.</p>

	<h2 id="PluginReference">Android Plugin for Gradle</h2>

	<p>The Android build system uses the Android plugin for Gradle to support the Gradle Domain
	Specific Language (DSL) and declarative language elements. See the
	<a href="{@docRoot}tools/building/plugin-for-gradle.html">Android Plug-in for Gradle</a> section for
	a description of the plugin and a link to the complete list of the supported Gradle DSL elements.</p>