Very cool. I've long wanted something that's a bit of a cross between a calculator and a numpad; something that could be used as a calculator or just to send symbols to the computer that are easier to type on such a device.

Question: the description says it has access to all the Greek alphabet letters but only the lower case ones are shown on the keypad: do you get (e.g. ∆) by using the shift key on the regular keyboard plus δ on the Mathpad?