Images: RIM shows off the BlackBerry Storm 2

The SurePress screen on the first BlackBerry Storm had a central pivot under it, making the screen very slightly convex and producing a tactile click when pressed. However, that design made it impossible to type quickly on the virtual keyboard, because the screen needed to bounce up again from each press before the next character could be typed.

The new version of SurePress, as implemented on the Storm 2, does away with the central pivot, replacing it with four electromechanical actuators that are controlled by the phone's software.

This makes it possible to press more than one character at a time — so, for example, the shift key can be pressed at the same time as a letter key. Tactile feedback can be felt for both presses.