Through iTunes
no why do you think its called trading in?
iOS 5 will be compatible with iPhone 3GS as well as iPhone 4.
Yes, you can put an iPhone camera in an iPhone 3GS provided you have the required skills.
iPhone 3GS. Then the iPhone 4 and then the iPhone 4S.
yes
yes , uu can .
No. The only iPhone that has the ability to FaceTime is the iPhone 4.
iPhone 4 ,however my father has the iPhone 3GS which is quite good.
Iphone 3GS- £399.99 (8 GB) Iphone 4 - £499.99 (16GB) Iphone 4 - £599.99 (32 GB) I would go for the Iphone 3GS because it is cheaper and wider screened. But the choice is totally up to you! Good Luck!
35000 is the price of iphone 3gs and 60000of iphone 4
the 3gs is much better for it's money iphone 3gs is better, i think. but it is very dear. it seems that you have enough money. if not, you can buy cheap phone instead.