Mixing SDL2 and Cocoa on iOS

After studying my case, I’ve come to the conclusion that my apps will work
better with the native iOS user interface rather than my original idea of
using an OpenGL GUI with SDL.

All my apps have a main OpenGL canvas, with toolbar icons at a side, as
well as some temporary panes (or “forms”) with controls (just like most iOS
apps for design or photo retouching).

Is there some way of mixing SDL and Cocoa for getting this kind of app?
How? Should be the Cocoa part a “child” of the SDL app, or vice versa?

Where should I put the connection between the two parts?