iPhone 3G or 3GS?

[Melfunction]

Might seem a lame question but how do you tell the difference between these two phones?

 

[Intell]

Physically, the 3Gs has shiny text on the back. The 3G has gray text.

 

[Crystal-RX]

3G does not have compass nor video function when you open its camera.

 

[Melfunction]

Right, thanks.