Activity for Android
This is the simplest game ever made - just start Activity, enable activity updates recording and keep your phone with you. It will magically detect you current activity and record its duration. If you are still longer than 1 hour it will remind you to take a break and walk.
This is more than activity tracker - it helps to keep you fit.
Application should be compatible with any phone or tablet with Google Play installed but may not detect activity updates correctly, it depends on actual device hardware!