Applicability of Fitts’ law to interaction with touchscreen: review of experimental results

Abstract Fitts’ law models human psychomotor behaviour and can be used to predict the time required to complete a movement task. Although originally proposed for physical apparatus, Fitts’ law has been adopted to study how human beings use various computer input devices to perform onscreen pointing tasks. Touchscreens are now used in smartphones, tablets and other digital devices. The applicability of Fitts’ law to the interaction with touchscreen has been studied for both stationary computers and mobile devices. Researchers have been studying this problem for about forty years, but the body of work remains small and there is no consensus on whether Fitts’ law is valid for touch-based interaction. This paper reviews studies reporting positive-, null- and negative results on the applicability of Fitts’ law to interaction with touchscreen and proposing modifications to Fitts’ law especially for modelling interaction with touchscreen.