The latest model iPod can be identified by its coloured back. The iPod 5th generation is available in various colours.
The 4th generation iPod Touch can be distinguished from previous models by the camera eye located on the front and reverse.
The Late 2009 Touch looks no different to the 2nd generation model, apart from having only two lines of text below the hard drive size on the silver reverse. The model number begins with MC.
The 2nd generation Touch can be identified by its metallic rim and slightly arched back. It has volume control buttons on the upper left side and the model number begins with MB or MC for the 8gb model.