How do you tell the difference between the new iphone & old one?

Question

my dad just bought me an iphone but i dont kno if its the new one or not..

which ones better? and is there a difference in appearance ..

mine says 3g on the box if that helps.

Answer 1

yes thats the new one. if the back is black or white and made of plastic, its the new one. if its metallic, its the old one. the new one is better, btw. i have one.  

Answer 2

thats the new one. but if you didnt have it come with the box, it should have some other new features...

Answer 3

THe new one is kinda thinner than the old one, it's made out of plastic. U have the new one if it says 3g.

i have one!!