Hi guyz,
Actually I have read about that I can write Objective-C app on Linux (using GNUStep). But my question is, Am I will be able to develop completely iPhone app on Linux machine? Or I'll need eventually need to use Mac machine? Especially when I read that there are some some syntax diffs between NeXT/Apple and GCC (according to http://en.wikipedia.org/wiki/Objective-C)
Short answer - yes it can be done but is not as easy as the Mac way.
Duplicate of how-much-of-an-iphone-app-can-be-developed-and-tested-on-linux, which will lead you to still more links, and 75-100 others.
I'd try giving VirtualBox and a Mac OS X guest a shot. Some people say they've been able to run it. http://forums.virtualbox.org/viewtopic.php?t=2076
If you manage to run it, then you could install X-Code and things should be a lot easier.