A method of registering an application on a mobile terminal in a mobile network with an application server, said mobile terminal comprising an identity module, said method comprising the steps of: receiving at the application server a first message for registering the application, said first message comprising a telephone number associated with the identity module; generating by the application server a unique identifier and associating the unique identifier with the telephone number; sending a second message from the application server to the mobile terminal, said second message comprising the unique identifier; and generating and storing at the mobile terminal a data block comprising the unique identifier, a subscriber identity associated with the identity module and a terminal identifier associated with the mobile terminal.