For data entry, you get a vertical row of buttons on the right side of the device labeled the same way as the alphanumeric keys on most phones (that is, 0 through 9, with letters on the 2 through 9 keys).
It's also highly customisable, allowing drivers to individually choose which bits and pieces to put into a one - touch verticalrowof «favourites» buttons on one side, cutting four - touch operations down to two.