A study with 18 test persons was done to get a better understanding of the usability of proximity detection and the evaluation of the minimum size of control elements. The test persons did two different tests on a smartphone with integrated proximity detection and the associated test application. Several tasks with changing states of the proximity detection were made. Differences of several parameters were determined on the basis of the collected data. It could be shown that the task completion had been simplified.
Smartphones and other mobile devices have small screens and are operated with fingers. This may lead to a fat finger problem (obscuration of the control elements) or the fingers define an imprecise area of contact. A current solution is the definition of minimum sizes for control elements by the manufacturers. Can the error rate of the interactions be minimized even with small buttons by means of proximity detection? Would the speed of the interaction increase by means of proximity detection? Can proximity recognition help to find certain entries in table lists more quickly?