You can also use the Capture OpenGL ES Frame option from the Debug menu, which will freeze the game for a while and totally change the content of the Debug menu to accommodate the new debugging environment. Finally, it shows you a frame debugger that contains all of the draw calls for OpenGL ES where you can see the construction and the rendering pipeline of the chosen frame. Also, you can check the used texture, shaders, and objects one by one. It is a more advanced tool, but it is very useful to use when you want to really understand how a frame gets rendered step by step.
From the changed Debug menu, you can go back and forth between the draw calls. Once you have finished investigating, you can go to the Debug menu again and choose Release OpenGL ES Frame. This will let the game keep running again on the device. Keep in mind that these options are available only when you have a game running on the device.