Abstract: A method of inhibiting a function of a multi-function portable personal communications device includes determining a first position of the personal communications device, after a predetermined time interval, determining a second position of the personal communications device, determining the distance between the first position and the second position, determining the time interval in which the personal communications device moved from the first position and the second position, calculating an average velocity of the personal communications device based on the first position, the second position and the time interval and, if the average velocity of the personal communication device exceeds a predetermined value, inhibiting a function of the personal communications device.