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      1 page.title=Optimizing for Battery Life
      2 page.metaDescription=Learn how to help your app go easier on the battery.
      3 
      4 meta.tags="performance"
      5 page.tags="performance"
      6 
      7 @jd:body
      8 
      9 <div id="qv-wrapper">
     10   <div id="qv">
     11     <h2>
     12       In this document
     13     </h2>
     14     <ol>
     15       <li>
     16         <a href="#lazy">Lazy First</a>
     17       </li>
     18       <li>
     19         <a href="#features">Platform Features</a>
     20       </li>
     21       <li>
     22         <a href="#toolery">Tooling</a>
     23       </li>
     24     </ol>
     25   </div>
     26 </div>
     27 
     28 <p>Battery life is the single most important aspect of the mobile user
     29 experience. A device without power offers no functionality at all.
     30 For this reason, it is critically important that apps be as respectful of
     31 battery life as possible.</p>
     32 
     33 <p>There are three important things to keep in mind in keeping your app
     34 power-thrifty:</p>
     35 <ul>
     36 <li>Make your apps <em>Lazy First</em>.</li>
     37 <li>Take advantage of platform features that can help manage your app's battery
     38 consumption.</li>
     39 <li>Use tools that can help you identify battery-draining culprits.</li>
     40 </ul>
     41 
     42 <h2 id="lazy">Lazy First</h2>
     43 
     44 <p>Making your app Lazy First means looking for ways to reduce and optimize
     45 operations that are particularly battery-intensive. The core questions
     46 underpinning Lazy First design are:
     47 
     48 <ul>
     49 
     50    <li><strong>Reduce:</strong> Are there redundant operations your app can cut
     51 out? For example, can it cache downloaded data instead of repeatedly waking
     52    up the radio to re-download the data?</li>
     53 
     54    <li><strong>Defer:</strong> Does an app need to perform an action right
     55    away? For example,
     56     can it wait until the device is charging before it backs data up to the
     57     cloud?</li>
     58 
     59    <li><strong>Coalesce:</strong> Can work be batched, instead of putting the
     60    device
     61    into an active state many times? For example, is it really necessary for
     62    several dozen apps to each turn on the radio at separate times to send
     63    their messages? Can the messages instead be transmitted during a
     64    single awakening of the radio?</li>
     65 </ul>
     66 
     67 <p>
     68 You should ask these questions when it comes to using the CPU,
     69 the radio, and the screen. Lazy First design is often a good way
     70 to tame these battery killers.
     71 </p>
     72 
     73 <p>
     74 To help you achieve these and other efficiencies, the Android platform
     75 provides a number of features to help maximize battery life.
     76 </p>
     77 
     78 <h2 id="features">Platform Features</h2>
     79 
     80 <p>
     81 Broadly speaking, the Android platform provides two categories of help
     82 for you to optimize your app's battery use. First, it provides several
     83 APIs that you can implement in your app. You can learn more about these APIs in
     84 <a href="/topic/performance/scheduling.html">Intelligent Job Scheduling</a>
     85 and <a href="/performance/power/network/index.html">
     86 Network Use and Battery Consumption</a>.
     87 </p>
     88 
     89 <p>
     90 There are also internal mechanisms in the platform to help conserve
     91 battery life. While they are not APIs that you implement programmatically,
     92 you should still be aware of them so that your app can leverage them
     93 successfully. For more information, see
     94 <a href="/training/monitoring-device-state/doze-standby.html">Doze and
     95 App Standby</a>.</p>
     96 
     97 <p>
     98 You can get even more benefit out of these features by using the tools
     99 available for the platform to discover the parts of your app that consume
    100 the most power. Finding what to target is a big step toward
    101 successful optimization.
    102 </p>
    103 
    104 <h2 id ="toolery">Tooling</h2>
    105 
    106 <p>There are tools for Android, including
    107 <a href="/studio/profile/dev-options-rendering.html">Profile GPU Rendering</a>
    108 and <a class="external-link"
    109 href="https://github.com/google/battery-historian">Battery Historian</a>
    110 to help you identify areas that you can optimize for better battery life.
    111 Take advantage of these tools to target areas where you can apply the
    112 principles of Lazy First.
    113 </p>
    114 
    115 <section class="dac-section dac-small" id="latest-games"><div class="wrap">
    116   <h2 class="norule" style="margin:0 0">More resources</h2>
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    125 </section>
    126