Possible Duplicate:
is there any way that we can develop application in .net for iphone
can xcode be used to develop iphone applications using .net and is it compatible with windows
Possible Duplicate:
is there any way that we can develop application in .net for iphone
can xcode be used to develop iphone applications using .net and is it compatible with windows
Take a look at Mono Touch. It lets you use .NET-style languages and tools to develop iPhone apps.
However, it won't be compatible with Windows. Mono Touch is basically a wrapper over Cocoa Touch. You still have to use Xcode (on a Mac) to build and distribute apps developed with Mono Touch.