Patent ID: 8669949

Claim:
An apparatus comprising: a casing; a power source of limited capacity to provide electric power to the apparatus; a motion sensor to sense movement of the casing; a touch sensor disposed on the casing and providing a touch-sensitive surface enabling a touch of a tip of a digit of a user to the touch-sensitive surface to be detected; a conductive ring disposed about the periphery of the touch-sensitive surface of the touch sensor enabling an approach of the tip towards the touch-sensitive surface to be detected; a sensor interface coupled to the touch sensor to monitor the touch-sensitive surface for an indication of a touch of the touch-sensitive by the tip and to monitor the conductive ring for an indication of an approach of the tip towards the touch-sensitive surface; a processing device able to access the sensor interface and the motion sensor; and a storage accessible to the processing device and storing a sequence of instructions that when executed by the processing device, causes the processing device to: place the apparatus in a lower power mode in response to an elapsing of a first predetermined time period without receiving an indication of the casing having been moved, without receiving an indication of the conductive ring detecting an approach of the tip, and without receiving an indication of a touch of the touch-sensitive surface by the tip, wherein the processing device disables monitoring of the touch-sensitive surface and the conductive ring, and awaits an indication from the motion sensor that the casing has been moved; place the apparatus in a partial power mode in response to receiving an indication from the motion sensor of the casing being moved following the apparatus being in the lower power mode, wherein the processing device disables monitoring of the touch-sensitive surface, and enables monitoring of the conductive ring for an indication of an approach of the tip towards the touch-sensitive surface; and place the apparatus in a higher power mode in response to receiving an indication from the conductive ring of the approach of the tip following the apparatus being in the partial power mode, wherein the processing device enables monitoring of the touch-sensitive surface for an indication of a touch by the tip.