Anyway to FAKE iPhone device?

Is there anyway I could fake my device so the app thinks I have an iPad 4 when I have an iPod 5. There's a game called Modern Combat 5 which lags on my iPod cause of the retina. And to fix it, I need to let the app think I have an iPad 4 which has an option in the game (app) to lower the graphics.

If you are good at this stuff, please help me.

Robot?