Square: 3×3 Keypad Mapped to Geometric Elements of a Square
Youngwoo Yoon, Geehyuk Lee · 2008
We introduce Square, a text entry device in the form of a small square button. Conceptually, it is equivalent to a 3times3 keypad since the nine geometric elements of the square - four vertices, four edges, and a face - play the part of the nine keys of a 3times3 keypad. Being small and simple, on the other hand, Square can allow more freedom to the design of a mobile device. In addition, it is suitable for blind typing due to the distinct tactile properties of the different elements of the square button.