A method for detecting a gesture in a geometric shape and controlling an electronic device includes providing a sensing assembly including at least one photoreceiver and a plurality of phototransmitters, wherein each phototransmitter emits infrared light away from the electronic device about a corresponding central transmission axis, wherein each central transmission axis is oriented in a different direction with respect to the others; and controlling the emission of infrared light by each of the phototransmitters during each of a plurality of time periods during movement of an external object in a geometric shape relative to the electronic device. For each of the plurality of phototransmitters and for each of the plurality of sequential time periods, a corresponding measured signal is generated which is indicative of a respective amount of infrared light which originated from that phototransmitter during that time period and was reflected by the external object prior to being received by the photoreceiver. The measured signals are evaluated over time to identify the geometric shape; and the electronic device is controlled in response to the identification of the geometric shape.