update: I realized several people forked this recently. This is an old version. New and optimized one could be found in my other repo: Tracking map on Android.
This application is used to track user's location regularly and store them into a database in the background. It will work even if user quits it. It has a turn on/off function for user to stop it.
In this application I use Sevice, AlarmManager, Fragment, SQLiteOpenHelper, Content Provider and LoaderManager classess. It runs on SDK 10 (2.3.3) and up. The Fragment class requires support package, which could be downloaded using Android SDK manager.
I build it as a research tool; feel free to fork or use it.