Got an Oyster card? Check your balance in a tap! -> on iPhone: use it wherever you have call coverage (not underground) -> on iPod touch: use it anywhere you have Wi-Fi access (at home, etc) You'll need to enter your Oyster online login details just once and it works over any internet connection (Wi-Fi/3G/EDGE/GPRS) This application is not affiliated with TfL/TranSys. The terms "Oyster" and "Oyster card" are a trademarks owned by TranSys Login details given to this app are sent over a secure connection to a third-party server