IJQwerty: What Difference Does One Key Change Make? Gesture Typing Keyboard Optimization Bounded by One Key Position Change from Qwerty

Despite of a significant body of research in optimizing the virtual keyboard layout, none of them has gained large adoption, primarily due to the steep learning curve. To address this learning problem, we introduced three types of Qwerty constraints, Qwerty1, QwertyH1, and One-Swap bounds in layout optimization, and investigated their effects on layout learnability and performance. This bounded optimization process leads to IJQwerty, which has only one pair of keys different from Qwerty. Our theoretical analysis and user study show that IJQwerty improves the accuracy and input speed of gesture typing over Qwerty once a user reaches the expert mode. IJQwerty is also extremely easy to learn. The initial upon-use text entry speed is the same with Qwerty. Given the high performance and learnability, such a layout will more likely gain large adoption than any of previously obtained layouts. Our research also shows the disparity from Qwerty substantially affects layout learning. To minimize the learning effort, a new layout needs to hold a strong resemblance to Qwerty.