A charger for handheld units is also an automatic backup unit for data stored in the handheld unit. The communication with the handheld unit is performed through a predefined object transfer protocol. By using an object transfer protocol, it is up to the handheld unit how to interact with the charger/backup unit when the communication has been initiated. Previous versions of the data may be stored and retrieved. It is possible to access the stored data and control the settings of the charger/backup unit from a handheld or a computer.