An example method includes determining, by one or more processors, an estimated location of a wearable computing device on a display device that is not presence-sensitive, wherein the wearable computing device is configured to be worn on a wrist of a user; causing the display device to output, at the estimated location, a graphical pattern; determining, by the one or more processors and based on optical data generated by an optical sensor of the wearable computing device, a refined location of the wearable computing device; and utilizing, by the one or more processors, the refined location of the wearable computing device as a location of user input for an application outputting a graphical user interface via the display device.