Abstract: An electronic watch, including a display featuring pixels, and a printed circuit board (PCB) surrounding the pixels, a first group of light detectors on the PCB on the right circumference of the pixels, that, when activated, output values of ambient light received by the detectors in that group, a second group of light detectors on the PCB on the left circumference of the pixels, that, when activated, output values of ambient light received by the detectors in that group, a processor connected to the first and second groups, that activates each group and stores the group output values, a computer-readable medium storing code which causes the processor to identify an in-air wave gesture by an object that traverses the airspace above the display, and a direction of the gesture, wherein the direction is left to right or right to left, based on outputs of the first and second groups.