An arrangement on a mobile computing device wherein actual motion of the device can be employed to control, among other things, the panning, zooming, paging and scrolling of a graphic user interface. Specifically, error diffusion according to the invention divides the input gray level intensity range into different segments for purposes of both thresholding and error diffusion. Device information, which indicates the type of subscriber data that the first telecommunications device is configured to process, is then sent from a first to a second telecommunications device.