Densha Otaku is a fantastic speedometer app that is particularly useful for train enthusiasts.
Not only is this app exquisitely designed, but it also utilizes the GPS functionality of your phone to present your speed on a visually stunning map that highlights the train tracks you are currently traversing.
• Record and monitor all of your speed records, including the map and time.
• Live Direction indicator.
• Works with imperial or metric system units.
If you happen to not be on a train, you can still appreciate the beautiful compass.