Question: Using [PyObjC](http://pyobjc.sourceforge.net/), you can use Python to write Cocoa applications for OS X. Can I write native iPhone apps using Python and if so, how?

Answer: 
Yes you can. You write your code in tinypy (which is restricted Python), then use tinypy to convert it to C++, and finally compile this with XCode into a native iPhone app. Phil Hassey has published a game called Elephants! using this approach. Here are more details,

<http://www.philhassey.com/blog/2009/12/23/elephants-is-free-on-the-app-store/>
[Pythonista](http://omz-software.com/pythonista) has an Export to Xcode feature that allows you to export your Python scripts as Xcode projects that build standalone iOS apps.

<https://github.com/ColdGrub1384/Pyto> is also worth looking into.