Comment Many Things (Score 1) 636
Do you know of any examples of open source iOS/OS X software that demonstrates this separation of writing the user interface in objective-c and the guts in something different (e.g., c++)?
The biggest example would be anything based on OpenCL, where you would do exactly that.
Also a number of games, use a shell of IOS framework stuff for things like game menus and leaderboards, but the actual game engines are C++ (and I'm not even talking about apps that use third party libraries like Unity).