There is described a method of controlling application access to predetermined functions of a mobile device. The described method comprises (a) providing a set of keys, each key corresponding to one of the predetermined functions (361, 362, 363, 364), (b) receiving (225) an application from an application provider (220, 221, 222, 223) together with information identifying a set of needed functions, and (c) generating a signed application (301, 302, 309) by signing the received application with each of the keys that correspond to one of the needed functions identified by the received information. There is also described a device for controlling application access and a system for controlling and authenticating application access. Furthermore, there is described a computer program and a computer program product.