Full Paper

Many eyes-free interaction techniques have been proposed for touchscreens, but few researches have studied human’s eyes-free pointing ability with mobile phones. In this paper, we investigate the single-handed thumb performance of eyes-free, absolute position control on mobile touch screens. Both 1D and 2D experiments were conducted. We explored the effects of target size and location on eyes-free touch patterns and accuracy. Our findings show that variance of touch points per target will converge as target size decreases. The centroid of touch points per target tends to be offset to the left of target center along horizontal direction, and shift toward screen center along vertical direction. Average accuracy drops from 99.6% of 2×2 layout to 85.0% of 4×4 layout, and average per target varies depending on the location of target. Our findings and design implications provide a foundation for future researches based on eyes-free, absolute position control using thumb on mobile devices.