fingerT9: leveraging thumb-to-finger interaction for one-handed text entry on smartwatches

We introduce FingerT9, leveraging the action of thumb-to-finger touching and the surface of the finger segments, to support one-handed text entry on smartwatches. This is achieved by mapping a T9 keyboard layout on the surface of finger segments, combined with a predictive input method. Our solution avoids the problems of fat finger and screen occlusion, and enables text entry using a single hand. Eyes-free text entry is made possible once users are familiar with the keyboard layout. In other words, users can focus on the screen output during typing without looking at the keyboard layout mapped on the surface of finger segments.