An apparatus capable of interacting with another device, includes: a module configured to provide a functionality, where the apparatus is configurable to support a second module for providing an additional functionality in order to permit variable functionality by the apparatus. The functionality may relate to an input-function and/or an output function. A method of providing functionality in a variable-function device, includes: removing a functionality from another device that can communicate with the variable-function device; and providing the removed functionality in the variable-function device.