So...You want to play some music on your phone but you want it to stop in 45 minutes because you're trying to fall asleep and don't want to run your battery down. Is there a way to do that?
The iPhone has had this feature built into it's clock/timer app for a very long time, but the Android community has not been able to do this very easily...until now.
Sleep Timer for Android can do exactly that. How to Geek's article gives you more details as well as the download link - check it out.