Method for using applications in a mobile station, a mobile station, and a system for effecting payments

A method for use in operating a mobile radio communication unit that comprises a controller coupled to an interface, the method comprising the steps of:

• providing at least one storage device that stores at least one application program and identification information, wherein the identification information identifies a user of the mobile radio communication unit;
• and
• mechanically and electrically coupling that at least one storage device to the interface so that the at least one storage device is attachable to the interface, for enabling the at least one storage device to be electrically coupled to the controller;
• wherein the at least one application relates to an electronic money purse residing at the mobile radio communication unit and having a balance of digital cash for making payments, wherein an external storage location stores a second user account having a second balance, and wherein further steps are performed of:
• retrieving at least a portion of the second balance from the second user account stored in the external storage location;
• and
• increasing the balance of digital cash in the electronic purse by an amount that is equal to the portion of second balance retrieved from the second user account.