While studying abroad, one of my classmate ended up in the suburbs of Barcelona because she fell asleep while traveling at night. It’s just a rite of passage for urban travelers, but it’s less than desirable. Likewise, iPhone developer, Tobias Domham realised there was a need for MetroNap after his girlfriend fell asleep on the New York Subway and ended up at Coney Island.

To use the app, simply pick your current stop and your destination stop. The app detects your location using your smartphone’s accelerator and notifies you when your stop is coming up. It’s a motion detector and alarm clock since there’s no easy GPS solution for underground travel.

Warning: this app might make you miss adventures to Coney Island!