Im new to this world of iphone apps, and need a kick in the right direction. im looking to make a calculator to work out a percentage of a sales price.
(ie $100,000 x 3% = $xx,xxx.xx)

I want the numbers in the label ($xx,xxx.xx) to calculate automatically as you type them in.

Ive followed heaps of tutorials & read up and i can make a calculator that works, but I have to have a "calculate" button- my problem is i want it to work it out automatically as you type.

Any suggestions?