An evaluation of stylus-based text entry methods on handheld devices in stationary and mobile settings

Effective text entry on handheld devices remains a significant problem in the field of mobile computing. On a personal digital assistant (PDA), text entry methods traditionally support input through the motion of a stylus held in the users dominant hand. In this paper, we present the design of a two-handed software keyboard for a PDA which specifically takes advantage of the thumb in the non-dominant hand. We compare our chorded keyboard design to other stylus-based text entry methods in an evaluation that studies user input in both stationary and mobile settings. Our study shows that users type fastest using the miniqwerty keyboard, and most accurately using our two-handed keyboard. We also discovered a difference in input performance with the mini-qwerty keyboard between stationary and mobile settings. As a user walks, text input speed decreases while error rates and mental workload increases; however, these metrics remain relatively stable in our two-handed technique despite user mobility.