title: Sync Android phone with a third-party server
body: <p>Do you know if the Android SDK provides some classes, interfaces or methods to help developers to create a mechanism in order to synchronize application data between the phone and a third-party server ?
  Or should we build this mechanism from scratch ?</p>
  
  <p>I've heard about C2DM for Push notification but it is available only from Android 2.2 and my application must support Android 2.1.</p>