Eyes-free text entry on a touchscreen phone

We present an eyes-free text entry technique for touchscreen mobile phones. Our method uses Graffiti strokes entered using a finger on a touchscreen. Although visual feedback is present, eyes-free entry is possible using auditory and tactile stimuli. In eyes-free mode, entry is guided by speech and non-speech sounds, and by vibrations. A study with 12 participants was conducted using an Apple iPhone. Entry speed, accuracy, and stroke formations were compared between eyes-free and eyes-on modes. Entry speeds reached 7.00 wpm in the eyes-on mode and 7.60 wpm in the eyes-free mode. Text was entered with an overall accuracy of 99.6%. KSPC was 9% higher in eyes-free mode, at 1.36, compared to 1.24 in eyes-on mode.