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</script><link href="../PRODUCT_PLUGIN/book.css" rel="stylesheet" type="text/css"/><link href="css/s60/style.css" rel="stylesheet" type="text/css" media="all"/></head><body onload="initPage();"><div class="body"><div class="contentLeft prTxt"><h1 class="pageHeading" id="GUID-159FCC18-2C9D-49F0-BAC1-DFEAADCF1D89">Saving battery time</h1><div><p>Mobile devices are not constantly connected to a power source but run on battery power. Latest devices are equipped with large color displays, multi-megapixel cameras, various radio transmitters, advanced multimedia, and other fancy features—all of which consume a lot of power. At the same time, more power-hungry applications that use the new possibilities are provided. Power optimization has become crucial to keep the device power consumption at an acceptable level and to prevent users from running out of battery time.</p>
<p>The amount of power an application consumes is affected by:</p>
<ul>
<li><p>Timers.</p></li>
<li><p>Backlight.</p></li>
<li><p>Network connections.</p></li>
<li><p><a href="GUID-B77C2006-879F-4AC6-B7BF-04B25B563A29.html#GUID-B77C2006-879F-4AC6-B7BF-04B25B563A29">Sensors</a>.</p></li>
</ul>
<p>For more tips on how to manage the power consumption of an application, see <a href="http://www.forum.nokia.com/main/resources/development_process/power_management/" target="_blank">Power Management</a> on Forum Nokia.</p>
<p>You can use the power information services to determine what the battery level is on a device and whether the charger is connected to the device. For more information, see <a href="GUID-6521F749-FA06-493B-A11D-B47F4DC0E6D6.html#GUID-6521F749-FA06-493B-A11D-B47F4DC0E6D6">Power information services</a>.</p>
<div><h3>Using timers</h3><p>You can use timers to update content that you fetch from the device. Observe the following guidelines:</p><ul>
<li><p>Turn off timers when they are no longer needed or when the application is moved to the background.</p></li>
<li><p> Do not fire timers at minimum intervals (for example, 10 ms) for long periods of time. Firing timers at longer intervals (for example, every 1 to 2 seconds) does not necessarily have a significant effect.</p></li>
</ul></div>
<div><h3>Using device backlight</h3><p>The backlight of the mobile device screen consumes energy. Do not override the default backlight settings unless it is absolutely necessary.</p></div>
<div><h3>Creating network connections</h3><p>Implement a reasonable schedule for retrieving data via network connections. For example, retrieve news data once in an hour. Optimize the amount of data that is transferred. For more information, see <a href="GUID-46FA9398-10C1-429F-B496-EC70E88F9CC7.html#GUID-46FA9398-10C1-429F-B496-EC70E88F9CC7">Retrieving data</a>.</p></div>
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