Measures time spent on each app. See which apps to uninstall because you're not using them!
The most accurate app usage tracker! Accurate to less than a second on Android 1.6 and up.

There are many applications that automatically start when you turn on your device; many of these you don't use or need, they just consume your valuable resources. Autorun Killer lets you manage applications that start up when you boot your device. Donate version even tries to prevent their restart (and is ad-free).