title: Android app: decrease battery usage
body: <p>I just finished an app that synchronizes its data with a server (runs SyncAdapter on background). I installed it on my phone, let it run on background (I barely used my phone) and I found out that the 23% of my applications' battery usage belongs to my app, so I really need to decrease  its battery usage.</p>
  
  <p>Right now I have the sync time set to 30 seconds. It's a multi-user app and if other users interact with you you get a notification, I can't set a sync time too high (actually I wanted to decrease it until I saw the battery usage). </p>
  
  <p>In each synchronization it ALWAYS asks the server for any changes and checks for changes in the local database. If there are changes in the local database they are sent to server, and if we retrieve changes from the server they are applied to the local database.</p>
  
  <p>Does anybody know about some tips to reduce battery usage?</p>