Disclaimer: I don't have any iOS devices. But AFAIK as a developer you can load anything you want onto your personal device including C/C++ and Ruby code. Check

Disclaimer: I don't have any iOS devices. But AFAIK as a developer you can load anything you want onto your personal device including C/C++ and Ruby code. Check out the Marmalade game engine for example - pure C/C++ for iOS. Getting it published it on the app store is another matter however.