My brief notes on concurrent programming facilities available in android. I will update it i find something interesting, do comment if you think that I missed something.
- Threads :- Plain old java threads! and synchronization primitives , classes in java.util.concurrent , java monitor objects – http://developer.android.com/reference/java/util/concurrent/package-summary.html
- Andorid Services – – http://developer.android.com/guide/components/services.html
- Loopers and Handlers :- http://developer.android.com/reference/android/os/Handler.html , http://www.vogella.com/tutorials/AndroidBackgroundProcessing/article.html. http://developer.android.com/reference/android/os/Looper.html
- Async Tasks :- http://developer.android.com/reference/android/os/AsyncTask.html
- IPC using Broadcast Receivers : http://developer.android.com/reference/android/content/BroadcastReceiver.html
- Alarm Manager :- http://developer.android.com/reference/android/app/AlarmManager.html
Sandeep's space 
Interesting topic. I’ll drop you a comment if I find anything else that fits in here.
Btw, many of the links above are not clickable!
Thanks for your feedback , its rather shabby work :D. I just updated it so that those links are clickable