 Most early Windows Mobile devices came with a stylus , which can be used to enter commands by tapping it on the screen . The primary touch input technology behind most devices were resistive touchscreens which often required a stylus for input . Later devices used capacitive sensing which does not require a stylus . Along with touchscreens , a large variety of form factors existed for the platform . Some devices featured <unk> keyboards , while others featured minimal face buttons . 
