Chatter2 Hardware keypad
Functionality
The layout is the one printed on the Chatter sticker

Each button can be pressed up to 4 times in quick succession to reach the second, third and fourth character listed under it. The shift button cycles between lowercase letters, uppercase, and numbers.
The top/left button (labelled UP/LEFT) is assigned to UP and opens the preregistered canned messages. Press SELECT to send, or CANCEL to go back. The next button (labelled DOWN/RIGHT) is assigned to RIGHT. The BACKSPACE button is assigned to the TAB function when SHIFT has been pressed once. To select a destination, press TAB (SHIFT once, then BACKSPACE) to highlight the destination field, then press RIGHT to cycle through the available destinations. Press SHIFT again to return each key to its first function.
Typing with any letter key opens a free text input panel. Press SELECT to send the message.