a compact input device for fast text input . ten perimeter regions are defined in a decagon shaped ring on a touch pad , and nine more center regions arranged in a 3 by 3 matrix are defined at the center of the perimeter regions . in alphanumeric mode , each of the ten perimeter regions represents a numeral or a character of the same order , found on a corresponding key of the ten numeric keys , 0 to 9 , found on a standard 12 - key telephone keypad . all perimeter regions synchronously switch to another group of characters of the same order , in accordance with the direction of a swipe on any of the perimeter regions . a tap on a perimeter region selects the character represented by the region at the moment . in addition , it is capable of operating in a standard 12 - key telephone keypad mode , pointing device mode , and symbol mode .