Evaluating Three Touch Gestures for Moving Objects across Folded Screens

Foldable screens are gaining popularity on mobile platforms as it features novel design schemes for view management and screen extension. However, challenges for performing touch input arises when it is folded in various angles and held in various ways. This paper is among the first to systematically evaluate how touch gestures perform under the influence of various fold angles and holding postures. Three gestures for moving objects on touch screens, namely Direct Drag, Hold & Tap, and Throw & Catch, were adopted from previous works and compared in a controlled experiment, where five fold angles and portrait vs landscape modes were varied. Results provide an in-depth understanding of how orientation, fold angle, target distance and direction affects the performance of each technique. Overall Direct Drag was the most accurate but highly inefficient and tiring. Hold & Tap was the most efficient technique with comparable accuracy, except being much more error-prone in Landscape than Portrait. Throw & Catch had a more balanced trade-off between efficiency and accuracy.