This app is able to wake you up few meters before you arrive at a public transport stop so you can fall deeply aslept without the fear of wake up after your stop and be late to office for example.
Just set an alarm at your destination and it will wake you up before you get there.
Runs in background and minimises battery use and continued use of GPS running in the background can dramatically decrease battery life.
It is recommended to quit the app from memory if you don't need it.
Requires iOS 4.3 or later.