This app is the best way to prevent overslept on the train.
Every subway station,which you use, needs to be registered in the app and turn it on to be active.
It tells a location of specified station by vibrating when your train approaches to the station.
By using Wi-Fi connections, this app enable to get your location without GPS.
As the name of locations appears on the screen by approaching to the station which you specified, you can check which station you passed through.
(Where:Subways, Train terminals, last train
When :For an appointment, for not to overslept on train)