Perfect for heavy duty spreadsheet users, this nifty new application for the iPhone and iPod Touch lets you use your mobile device as an ad-hoc numeric keypad for your Mac. Just install Balmuda’s Numberkey connect software onto your Mac, then grab the mobile app from the App Store for $1.99. The two pieces of software communicate via Wi-Fi, adding a familiar 18-key numeric keyboard to your Mac without wires.

Numberkey includes four different skins, including black on white, white on black, old school Mac and a recently added black on silver for new MacBook Pro users. While the lack of tactile feedback might slow you down a little bit, I still think it’s still convenient to have the extra keys.

At this point, Numberkey is a Mac only app, so Windows users need not apply. Now if they could only figure out how to fit the whole MacBook inside the iPhone, I’d be set.