Hi! I have a demo project, which loads and presents a Wavefront OBJ under Cocos2d 2.x!
In the app, there are touch control bars (separated by narrow lines) on the left and the right side of the (landscape) screen. Slide a finger on each of those to scale object, or move on the z-axis. By sweeping rest of the screen you can move the object (x,y).
The demo project can be downloaded here on my Dropbox!