Question : Learning curve from Windows Mobile to iPhone

First What language is used to develop iPhone apps?

I have a WM 6.1 app developed in C#.  Client says they think they are better off with iPhone app.  If I wanted to develop the iPhone how much of a learnign curve is there?  What would I need to learn?

Answer : Learning curve from Windows Mobile to iPhone

You'd need to familiarise yourself with Xcode (Apple's development platform), and learn Objective C.

I speak Java fluently, but had quite a lot of trouble getting accustomed with ObjC (to the point that I gave up). But you've got a different background  (and experience) than me.

An excellent resource for ObjC is a series of lectures from Stanford, focused on iPhone dev (http://itunes.stanford.edu/)

Good luck:)