Abstract: A portable radiotelephone device is provided that includes a body having provided on one or more exposed surface thereof one or more electrical contacts for one or more respective electrical input/output devices. The electrical contacts are covered with one or more layers of electro-resistive material. The electro-resistive material in the relaxed condition being an electrical insulator and in the stressed state being an electrical conductor. The arrangement is such that to effect electrical connection between any of the one or more electrical contacts with respective one or more electrical input/output devices, respective contacts and input/output devices are mutually engaged so as to load the elasto-resistive material under compression.

Abstract: A joystick controller for a portable radio communication device in which a ring of elasto-resistive material which when relaxed acts as an insulator, and when stressed acts as a conductor is positioned below the joystick lever of the controller and above four pairs of contact pads arranged in a circle, and the elasto-resistive material is used to transduce the movement of the joystick lever so as to provide an electrical signal output indicative of the amount of movement of the joystick lever.