It does run a full Python 2 and 3 IDE called Pythonista, including support for making graphical applications, debugging, and even running a limited shell called StaSH with a bunch of PyPy versions of a typical POSIX userland.

There are other IDEs for other languages, too, although Pythonista is the star at the moment.

So it's not as though programming, even graphical using UIKit, isn't possible just because there's no Xcode.