How close is iTGB source to TGB?

I'm thinking of delving into the world of iTGB for my next project. But I'd like to do some engine modding. Is the code structured similar to TGB? I'd assume it's all Objective-C now. But could I find a class / function such as t2dSceneWindow::onRender?

The reason I ask is that I've done quite a few mods in TGB that I'd like to carry over to iTGB in the event that I decide to develop an iPhone game. :)