am 05f80337: resolved conflicts for merge of ab6d5376 to mnc-dev

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page.title=Android, the world's most popular mobile platform

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@jd:body

<p>Android powers hundreds of millions of mobile devices in more than 190

countries around the world. It's the largest installed base of any mobile platform

and growing fast—every day another million users power up their

Android devices for the first time and start looking for apps, games,

and other digital content. </p>

<p>Android gives you a world-class platform for creating apps and games for

Android users everywhere, as well as an open marketplace for distributing

to them instantly.</p>

<h3>Global partnerships and large installed base</h3>

<p>Building on the contributions of the open-source Linux community and more

than 300 hardware, software, and carrier partners, Android has rapidly become

the fastest-growing mobile OS.</p>

<blockquote>Every day more than a million new Android devices are activated worldwide.</blockquote>

<p>Android’s openness has made it a favorite for consumers and developers alike,

driving strong growth in app consumption. Android users download more than 

billions of apps and games from Google Play each month. </p>

<p>With its partners, Android is continuously pushing the boundaries of hardware and software

forward to bring new capabilities to users and developers. For developers, 

Android innovation lets you build powerful, differentiated applications

that use the latest mobile technologies.</p>

<h3>Rapid innovation</h3>

<p>Android is continuously pushing the boundaries of hardware and software

forward, to bring new capabilities to users and developers. For developers, the

rapid evolution of Android technology lets you stay in front with powerful,

differentiated applications.</p>

<p>Android gives you access to the latest technologies and innovations across a

multitude of device form-factors, chipset architectures, and price points. From

multicore processing and high-performance graphics to state-of-the-art sensors,

vibrant touchscreens, and emerging mobile technologies.</p>

<h3>Powerful development framework</h3>

<blockquote>Easily optimize a single binary for phones, tablets, and other devices.</blockquote>

<p>Android gives you everything you need to build best-in-class app experiences.

It gives you a single application model that lets you deploy

your apps broadly to hundreds of millions of users across a wide range of

devices&mdash;from phones to tablets and beyond.</p>

<p>Android also gives you tools for creating apps that look great and take

advantage of the hardware capabilities available on each device. It

automatically adapts your UI to look its best on each device, while giving you

as much control as you want over your UI on different device

types. </p> 

<p>For example, you can create a single app binary that's optimized for

both phone and tablet form factors. You declare your UI in lightweight sets of XML

resources, one set for parts of the UI that are common to all form factors and

other sets for optimzations specific to phones or tablets.

At runtime, Android applies the correct resource sets based on its screen size,

density, locale,

and so on.</p>

<p>To help you develop efficiently, the <a href="{@docRoot}tools/index.html">Android 

    Developer Tools</a>

offer a full Java IDE with advanced features for developing, debugging, and

packaging Android apps. Using the IDE, you can develop on any available Android

device or create virtual devices that emulate any hardware configuration.</p>

<blockquote>1.5 billion downloads a month and growing. Get your apps in front

of millions of users at Google's scale.</blockquote>

<h3>Open marketplace for distributing your apps</h3>

<p>Google Play is the premier marketplace for selling and distributing Android apps.

When you publish an app on Google Play, you reach the huge installed base of

Android.</p>

<div style="float:left;margin-right:24px;margin-top:12px;">

<img src="{@docRoot}images/gp-device.png">

</div>

<p>As an open marketplace, Google Play puts you in control of how you sell your

products. You can publish whenever you want, as often as you want, and to the

customers you want. You can distribute broadly to all markets and

devices or focus on specific segments, devices, or ranges of hardware

capabilities.</p>

<p>You can monetize in the way that works best for your business&mdash;priced or

free, with in-app products or subscriptions—for highest engagement and

revenues. You also have complete control of the pricing for your apps

and in-app products and can set or change prices in any supported currency at

any time.<p>

<p>Beyond growing your customer base, Google Play helps you build visibility and

engagement across your apps and brand. As your apps rise in popularity, Google

Play gives them higher placement in weekly "top" charts and rankings, and for

the best apps promotional slots in curated collections.

</p>

<p>Preinstalled on hundreds of billions of Android devices around the world,

Google Play can be a growth engine for your business.</p>

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@jd:body

<div style="float:right;">

  <img src="{@docRoot}images/home/l-hero_2x.png" srcset="/images/home/l-hero.png 1x, /images/home/l-hero_2x.png 2x">

</div>

<p>Welcome to Android 5.0 Lollipop&mdash;the largest and most ambitious release for Android yet!</p>

<p>This release is packed with new features for users and thousands of new APIs for developers. It extends Android even further, from phones, tablets, and wearables, to TVs and cars.</p>

<p>For a closer look at the new developer APIs, see the

<a href="{@docRoot}about/versions/android-5.0.html">Android

5.0 API Overview</a>. Or, read more

about Android 5.0 for consumers at

<a href="http://www.android.com/versions/lollipop-5-0/"

>www.android.com</a>.</p>

  <div style="padding:0px 0px 0px 20px;float:right;margin:0 -10px 0 0">

    <img src="{@docRoot}images/home/l-hero_2x.png" srcset="{@docRoot}images/home/l-hero.png 1x, {@docRoot}images/home/l-hero_2x.png 2x" width="460" height="300" >

  </div>

  <div class="landing-docs" style="float:right;clear:both;margin:68px 0 2em 3em;">

  <div class="col-4 normal-links highlights" style="font-size:12px;">

    <h3 id="thisd" >Key Developer Features</h3>

<div id="qv-wrapper">

<div id="qv">

  <h2>Key developer features</h2>

  <ol>

      <ul style="list-style-type:none;">

        <li><a href="#Material">Material design</a></li>

        <li><a href="#Perf">Performance focus</a></li>

        <li><a href="#WebView">Chromium WebView</a></li>

        <li><a href="#Accessibility">Accessibility & input</a></li>

        <li><a href="#Battery">Tools for battery-efficient apps</a></li>

    </ul>

      </ol>

</div>

</div>

<p>Welcome to Android 5.0 Lollipop&mdash;the largest and most ambitious release for Android yet!</p>

<p>This release is packed with new features for users and thousands of new APIs for developers. It extends Android even further, from phones, tablets, and wearables, to TVs and cars.</p>

<p>For a closer look at the new developer APIs, see the

<a href="{@docRoot}about/versions/android-5.0.html">Android

5.0 API Overview</a>. Or, read more

about Android 5.0 for consumers at

<a href="http://www.android.com/versions/lollipop-5-0/"

>www.android.com</a>.</p>

<p class="note">

  <strong>Note:</strong> The Android 5.1 Lollipop MR1 update is available with additional features

  and fixes. For more information, see the

  <a href="{@docRoot}about/versions/android-5.1.html">Android 5.1 API Overview</a>.

</p>

<h2 id="Material">Material design</h2>

<p>Android 5.0 brings <a href="http://www.google.com/design/spec">Material design</a> to Android and gives you an expanded UI toolkit for integrating the new design patterns easily in your apps.  </p>

<p>New <strong>3D views</strong> let you set a z-level to raise elements off of the view hierarchy and cast <strong>realtime shadows</strong>, even as they move.</p>

<p>Built-in <strong>activity transitions</strong> take the user seamlessly from one state to another with beautiful, animated motion. The material theme adds transitions for your activities, including the ability to use <strong>shared visual elements</strong> across activities.</p>

<div style="width:290px;margin-right:35px;float:left">

<div style="float:left;max-width:280px;margin-right:1em;">

  <div class="framed-nexus5-port-span-5">

  <video class="play-on-hover" autoplay="">

    <source src="/design/material/videos/ContactsAnim.mp4">

    <source src="/design/videos/ContactsAnim.webm">

    <source src="/design/videos/ContactsAnim.ogv">

    <source src="{@docRoot}design/material/videos/ContactsAnim.mp4">

    <source src="{@docRoot}design/videos/ContactsAnim.webm">

    <source src="{@docRoot}design/videos/ContactsAnim.ogv">

  </video>

</div>

  <div style="font-size:10pt;margin-left:20px;margin-bottom:30px">

  <p style="img-caption">

    <em>To replay the movie, click on the device screen</em>

  </p>

</div>

</div>

<p>Ripple animations are available for buttons, checkboxes, and other touch controls in your app.

<p>Ripple animations are available for buttons, checkboxes, and other touch controls in your app.</p>

<p>You can also define vector drawables in XML and animate them in a variety of ways. Vector drawables scale without losing definition, so they are perfect for single-color in-app icons.</p>

<p>A new system-managed processing thread called <strong>RenderThread</strong> keeps animations smooth even when there are delays in the main UI thread. </p>

<h2 id="Perf">Performance focus</h2>

<p>Android 5.0 provides a faster, smoother and more powerful computing experience.</p>

<h2 id="Notifications">Notifications</h2>

<div style="float:right;clear:left;margin:1em;">

<img src="{@docRoot}images/versions/notification-headsup.png" />

</div>

<p>Notifications in Android 5.0 are more visible, accessible, and configurable. </p>

<img src="{@docRoot}images/versions/notification-headsup.png" style="float:right; margin:0 0 40px 60px" width="300" height="224" />

<p>Varying notification details may appear <strong>on the lock screen</strong> if desired by the user. Users may elect to allow none, some, or all notification content to be shown on a secure lock screen. </p>

<p>A new media notification template provides consistent media controls for notifications with up to 6 action buttons, including custom controls such as "thumbs up"&mdash;no more need for RemoteViews!</p>

<h2 id="TV">Your apps on the big screen</h2>

<p><a href="http://developer.android.com/tv/index.html">Android TV</a> provides a complete TV platform for your app's big screen experience. Android TV is centered around a simplified home screen experience that allows users to discover content easily, with personalized recommendations and voice search.</p>

<p>The TV Input Framework provides access to a wide variety of live TV input sources and brings them together in a single user interface for users to browse, view, and enjoy content. Building a TV input service for your content can help make your content more accessible on TV devices.</p>

<img src="{@docRoot}images/versions/recents_screen_2x.png" srcset="{@docRoot}images/versions/recents_screen.png 1x, {@docRoot}images/versions/recents_screen_2x.png 2x" style="float:right; margin:0 0 40px 60px" width="300" height="521" />

<h2 id="Documents">Document-centric apps</h2>

<div style="float:right;margin:1em;max-width:320px">

<img src="{@docRoot}images/versions/recents_screen_2x.png"

    srcset="/images/versions/recents_screen.png 1x, /images/versions/recents_screen_2x.png 2x" />

<p class="img-caption">Document-centric recents.</p>

</div>

<p>Android 5.0 introduces a redesigned Overview space (formerly called Recents) that’s more versatile and useful for multitasking.</p>

<p>New APIs allow you to show separate activities in your app as individual documents alongside other recent screens.</p>

<p>You can take advantage of concurrent documents to provide users instant access to more of your content or services. For example, you might use concurrent documents to represent files in a productivity app, player matches in a game, or chats in a messaging app. </p>

<h2 id="Connectivity">Advanced connectivity</h2>

<p>Android 5.0 adds new APIs that allow apps to perform concurrent operations with <strong>Bluetooth Low Energy</strong> (BLE), allowing both scanning (central mode) and advertising (peripheral mode).</p>

<p>Support for <strong><a href="http://www.khronos.org/opengles/3_X/">Khronos OpenGL ES 3.1</a></strong> now provides games and other apps the highest-performance 2D and 3D graphics capabilities on supported devices. </p>

<p>OpenGL ES 3.1 adds compute shaders, stencil textures, accelerated visual effects, high quality ETC2/EAC texture compression, advanced texture rendering, standardized texture size and render-buffer formats, and more.</p>

<div class="figure" style="width:350px; margin:0 0 0 60px">

<img src="{@docRoot}images/versions/rivalknights.png" style="float:right;" width="350" height="525" />

<div style="float:right;margin:1em;max-width:350px">

<img src="{@docRoot}images/versions/rivalknights.png"  />

<p class="img-caption">Gameloft's Rival Knights uses ASTC (Adaptive Scalable Texture Compression) from AEP and Compute Shaders from ES 3.1 to deliver HDR (High Dynamic Range) Bloom effects and provide more graphical detail.</p>

</div>

<p>OpenGL ES 3.1 adds compute shaders, stencil textures, accelerated visual effects, high quality ETC2/EAC texture compression, advanced texture rendering, standardized texture size and render-buffer formats, and more.</p>

<p>Android 5.0 also introduces the <strong>Android Extension Pack</strong> (AEP), a set of OpenGL ES extensions that give you access to features like tessellation shaders, geometry shaders, ASTC texture compression, per-sample interpolation and shading, and other advanced rendering capabilities. With AEP you can deliver high-performance graphics across a range of GPUs.</p>

<p>Android now includes support for standard <strong>USB audio</strong> peripherals, allowing users to connect USB headsets, speakers, microphones, or other high performance digital peripherals. Android 5.0 also adds support for <strong>Opus</strong> audio codecs.</p>

<p>New <strong>{@link android.media.session.MediaSession}</strong> APIs for controlling media playback now make it easier to provide consistent media controls across screens and other controllers.</p>

<p>New <strong><code><a href="{@docRoot}reference/android/media/session/MediaSession.html">MediaSession</a></code></strong> APIs for controlling media playback now make it easier to provide consistent media controls across screens and other controllers.</p>

<h2 id="Camera">Enhanced camera &amp; video</h2>

<p>Android 5.0 also adds support for <strong>multimedia tunneling</strong> to provide the best experience for ultra-high definition (4K) content and the ability to play compressed audio and video data together. </p>

<h2 id="Work">Android in the workplace</h2>

<div class="figure" style="width:320px; margin:1em 0 0 20px;padding-left:2em;">

<img style="float:right; margin:0 1em 1em 2em"

<div style="float:right;margin:1em;max-width:330px">

<img 

    src="{@docRoot}images/android-5.0/managed_apps_launcher@2x.png"

    srcset="{@docRoot}images/android-5.0/managed_apps_launcher@2x.png 2x"

    alt="" width="300" />

    srcset="/images/android-5.0/managed_apps_launcher@2x.png 2x"

    alt="" />

<p class="img-caption">Users have a unified view of their personal and work apps, which are

badged for easy identification.</p>

</div>

<h2 id="Work">Android in the workplace</h2>

<p>To enable bring-your-own-device for enterprise environments, a new

<a href="{@docRoot}about/versions/android-5.0.html#Enterprise">managed provisioning process</a>

creates a secure work profile on the device. In the launcher, apps are shown with a Work badge to

issue these devices with a device owner app already installed that

can configure global device settings.</p>

<h2 id="ScreenCapture">Screen capturing and sharing</h2>

<p>Android 5.0 lets you add screen capturing and screen sharing capabilities to your app. </p>

<p>New <strong>interaction composite sensors</strong> are now available to detect special interactions such as a <em>wake up</em> gesture, a <em>pick up</em> gesture, and a <em>glance</em> gesture.</p>

<h2 id="WebView">Chromium WebView</h2>

<div style="float:right;margin:1em 2em 1em 2em;">

  <img src="/images/kk-chromium-icon.png" alt="" height="160" style="margin-bottom:0em;">

  <img src="{@docRoot}images/kk-chromium-icon.png" alt="" height="160" style="margin-bottom:0em;">

</div>

<p>The initial release for Android 5.0 includes a version of Chromium for {@link android.webkit.WebView} based on the Chromium M37 release, adding support for <strong>WebRTC</strong>, <strong>WebAudio</strong>, and <strong>WebGL</strong>. </p>

<p>The initial release for Android 5.0 includes a version of Chromium for <code><a href="{@docRoot}reference/android/webkit/WebView.html">WebView</a></code> based on the Chromium M37 release, adding support for <strong>WebRTC</strong>, <strong>WebAudio</strong>, and <strong>WebGL</strong>. </p>

<p>Chromium M37 also includes native support for all of the <strong>Web Components</strong> specifications: Custom Elements, Shadow DOM, HTML Imports, and Templates. This means you can use <a href="http://polymer-project.org/">Polymer</a> and its <a href="https://www.polymer-project.org/docs/elements/material.html">material design elements</a> in a WebView without needing polyfills.</p>

<p>As new versions of Chromium become available, users can update from Google Play to ensure they get the latest enhancements and bug fixes for WebView, providing the latest web APIs and bug fixes for apps using WebView on Android 5.0 and higher.</p>

<h2 id="Accessibility">Accessibility &amp; input</h2>

<p>New accessibility APIs can retrieve detailed information about the properties of windows on the screen that sighted users can interact with and define standard or customized input actions for UI elements.</p>

<p>New Input method editor (IME) APIs enable faster switching to other IMEs directly from the input method.</p>

<h2 id="Battery">Tools for building battery-efficient apps</h2>

<p>New <strong>job scheduling</strong> APIs allow you optimize battery life by deferring jobs for the system to run at a later time or under specified conditions, such as when the device is charging or connected to Wi-Fi.</p>

<p>A new <code>dumpsys batterystats</code> command generates <strong>battery usage statistics</strong> that you can use to understand system-wide power use and understand the impact of your app on the device battery. You can look at a history of power events, approximate power use per UID and system component, and more.</p>

<img src="{@docRoot}images/versions/battery_historian.png" srcset="{@docRoot}images/versions/battery_historian@2x.png 2x" alt="" width="760" height="462" />

<img src="{@docRoot}images/versions/battery_historian.png" srcset="/images/versions/battery_historian@2x.png 2x" alt="" width="760" height="462" />

<p class="img-caption">Battery Historian is a new tool to convert the statistics from <code>dumpsys batterystats</code> into a visualization for battery-related debugging. You can find it at <a href="https://github.com/google/battery-historian"

>https://github.com/google/battery-historian</a>.</p>

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<section class="dac-section dac-section-light"><div class="wrap">

<section class="dac-section dac-light"><div class="wrap">

  <h1 class="dac-section-title">Tools for building apps</h1>

  <div class="dac-section-subtitle">

    Insights into Android's tools and libraries to speed your development.

  </ul>

</div></section>

<section class="dac-section dac-light"><div class="wrap">

<section class="dac-section dac-section-light"><div class="wrap">

  <h1 class="dac-section-title">Android performance patterns</h1>

  <div class="dac-section-subtitle">

    Everything you need to know about improving your app’s performance.

  data in AdMob</a> and have the full picture of your app revenue.

</p>

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