Existing mobile phones use the front screen for gesture interactions, but they often suffer from usability problems such as content occlusion and spurious triggering caused by fat finger errors. Recent advances in new sensor technologies have made it possible for modern mobile phones to recognize gesture inputs on the rear screen. Although inputs from the backside of a mobile phone have demonstrated their usefulness for simple interaction tasks such as target acquisition, little is known regarding the best practices in gesture design for complex concurrent tasks on dual-screen mobile devices. Therefore, we conducted a three-stage study to explore user-defined multi-finger gestures for concurrent game tasks on a dual-screen mobile device. Experimental results indicate the existence of a consensus between participants regarding gesture choices for specified game tasks. Based on this consensus, we developed a gesture taxonomy and generated a set of user-defined gestures for dual-screen mobile devices. A subsequent benchmark test validated the popularity of the user-defined gestures with both ordinary and professional game players.

现有的移动电话使用前屏进行手势交互，但是它们经常遭受可用性问题，例如内容遮挡和由胖手指错误引起的虚假触发。新传感器技术的最新进展使现代手机能够识别后屏幕上的手势输入。尽管来自手机背面的输入已经证明了其对诸如目标获取之类的简单交互任务的有用性，但对于双屏移动设备上的复杂并发任务的手势设计最佳实践知之甚少。因此，我们进行了三个阶段的研究，以探索用户定义的多指手势在双屏移动设备上同时执行游戏任务。实验结果表明，参与者之间对于指定游戏任务的手势选择存在共识。基于这种共识，我们开发了手势分类法，并为双屏移动设备生成了一组用户定义的手势。随后的基准测试验证了用户定义的手势在普通和专业游戏玩家中的受欢迎程度。