you could do so by unlocking the phone 3 ways call att get authorized unlock use thin sim to unlock install software on the phone to unlock otherwise the phone is locked to the carrier att i would suggest doing the thin sim unlock because att very rarely does unlock and it would be the fastest way you can purchase the sims online just search in Google and do some research
Yes
Yes it does.
of course
No. The iPhone 3GS is sadly a GSM only phone, so it cannot function on Sprint (or Verizon's) bandwidths.
I tried it with my 3GS and it does work.
Probably not, they have different exterior shapes.
iPhone 3gs
iPhone 3GS
the iphone 3gs replaced the iphone 3g.
Dose the iphone 3gs have a radio
If you mean,' Do iPhone 3GS's have Verizonservice?'No, not anymore, as of 17/10/2011 you can only get the iPhone 3GS on AT&T!
no why do you think its called trading in?