How can I modify my existing app to support an earlier version of the Android OS?

I upgraded my app from Android 2.1 (Eclair) to Android 2.2 (Froyo), but I didn't realize that most of my users are still running Android 2.1. Now they can'开发者_C百科t get the update anymore. Can I downgrade my app to Android 2.1?

You need to set the minSDKVersion (API 7 is is 2.1 compatible, I believe) to the appropriate API in the manifest and make sure all your code is compliant. You can find information about this in the Android documentation