1. A method comprising: receiving active time accumulation information over a communication interface, wherein the active time accumulation information represents a sum of time periods during which an instantaneous motion intensity value determined from motion data meets predefined activity criteria, wherein the motion data represents local movement of a portable electronic device; executing a game application with encoded instructions; transferring the active time accumulation information to the game application; and controlling the game application with a parameter proportional to the active time accumulation information.