By providing an open development platform, Android offers developers the ability to build extremely rich and innovative applications. Developers are free to take advantage of the device hardware, access location information, run background services, set alarms, add notifications to the status bar, and much, much more.
List of open source Android applications
http://en.wikipedia.org/wiki/List_of_open_source_Android_applications10 Open Source Android Apps which every Android developer must look into
http://sudarmuthu.com/blog/2010/04/03/10-open-source-android-apps-which-every-android-developer-must-look-into.html"I used to read code from popular open source projects to see how others implement certain functionalitie
s and also to learn from them. (I am a firm believer of the fact that you have to read good code to write good code)
Recently I have been following up a couple of good open source Android apps and thought of listing them here so that it could be useful for others.
Sample Apps by Android Team
Could there be a better way to start without looking at the code of the developers who developed the framework? These are 15 different android sample apps created by the core developers of the Android framework. These include a couple of games, photostream, time display, home screen shortcuts etc."
But yea ur right, unless the creator makes the app open source then it's not.