A portable data carrier (10) and a method (B1-B10), as well as a storage medium with instructions, for transferring data by means of a portable data carrier are provided. The portable data carrier comprises a carrier storage (12) for storing data containing a biometric template (13) and an application-specific function (15) as well as carrier communication means (11) for contactless receipt and transmission of data. The portable data carrier is characterised in that it further comprises carrier processing means (16) for comparing the biometric template with a biometric sample (23) received from an external arrangement (20), and that it is arranged to complete a handshake process with the external arrangement as well as perform the application-specific function and transmit a result of the same to the external arrangement, only if the biometric sample matches the biometric template.