I've been playing with WebGL quite a bit lately and I really dig Three.js. It's really lightweight and just serves as something that makes wrangling most of the GL calls a bit easier, and provides a quick way of creating basic primatives like a sphere.
Now, in native land, it seems that all the frameworks want to be so much more than that. Things like Oolong, UDK, Unity, Cocos, etc. I did a bit of googling, and the closest thing I could find was iSGL3D but I'm not thoroughly convinced it is the right answer.
Is there something more similar to Three.js that is written in native C, C++ or Objective-C that I can't find?
Here is a port of three to C++: https://github.com/jdduke/three_cpp
Core - 75% complete (TODO: Morph targets, shadows, plugin support)
Extras - 5-10% complete (TODO: Pretty much everything)
Examples - 25% complete (TODO: Examples involving morph targets an)