A device to detect a touch-less gesture made by an object, the device comprising: a collection engine configured to collect light intensity measurements of light intensity at two or more measurement cycles from two or more ambient light sensors arranged at respective surface locations of the device; a processor configured to identify the gesture based on a comparison of the light intensity measurements at each of the two or more ambient light sensors at two or more of the two or more measurement cycles with a gesture template comprising light intensity measurements for a plurality of known gestures; and a memory device configured to store a gesture library that associates the gesture with an output signal; wherein the collection engine outputs for each of the two or more measurement cycles the light intensity measurements collected from each of the two or more ambient light sensors at the respective measurement cycle as a frame of data; wherein the processor identifies the gesture by processing the frames of data output by the collection engine, the processing including the processor comparing for the two or more of the two or more measurement cycles the light intensity measurements of the corresponding frames of data with each other and using a process of elimination of other gestures among a set of gestures, the set of gestures forming part of the plurality of known gestures for which the gesture template comprises light intensity measurements, and the process of elimination of other gestures among the set of gestures including comparing for the two or more of the two or more measurement cycles the light intensity measurements of the corresponding frames of data with the light intensity measurements comprised in the gesture template for the set of gestures; and wherein, when the processor identifies the gesture, the processor stops the processing of subsequent ones of the frames of data output by the collection engine to identify the gesture until a trigger signal is received. a collection engine configured to collect light intensity measurements of light intensity at two or more measurement cycles from two or more ambient light sensors arranged at respective surface locations of the device; a processor configured to identify the gesture based on a comparison of the light intensity measurements at each of the two or more ambient light sensors at two or more of the two or more measurement cycles with a gesture template comprising light intensity measurements for a plurality of known gestures; and a memory device configured to store a gesture library that associates the gesture with an output signal; wherein the collection engine outputs for each of the two or more measurement cycles the light intensity measurements collected from each of the two or more ambient light sensors at the respective measurement cycle as a frame of data; wherein the processor identifies the gesture by processing the frames of data output by the collection engine, the processing including the processor comparing for the two or more of the two or more measurement cycles the light intensity measurements of the corresponding frames of data with each other and using a process of elimination of other gestures among a set of gestures, the set of gestures forming part of the plurality of known gestures for which the gesture template comprises light intensity measurements, and the process of elimination of other gestures among the set of gestures including comparing for the two or more of the two or more measurement cycles the light intensity measurements of the corresponding frames of data with the light intensity measurements comprised in the gesture template for the set of gestures; and wherein, when the processor identifies the gesture, the processor stops the processing of subsequent ones of the frames of data output by the collection engine to identify the gesture until a trigger signal is received.