Sprint doesn't use SIM cards...
yes. once an iphone is universally unlocked it will work.
no unless it is unlocked... .
Yes if you buy an iphone and use geohot's black snow and get an international sprint sim
No because even if it is unlocked sprint works on a CDMA and AT&T works on a gsm signal it's like trying to use AM on FM radio only
YES it should although if its jailbroken/unlocked it will lock
Yes. Unlocked iPhones do work on the Orange network in Israel. One just needs an appropriate 3G sim card.
if you bought if with orange or have jailbroken and unlocked it then yes is should work fine.
If the handset has been unlocked from its original network, then yes.
no
No, You cannot use reliance CDMA sim card (or) any other CDMA card sim card on Apple iphone 4s. Any GSM Sim card will work on factory unlocked Apple iphone 4s but not CDMA sim ONLY IN INDIA.
Just like any other unlocked phone, a unlocked treo basically is not limited to a particular mobile carrier. For example, a phone locked by Sprint can only work on the Sprint network. If you put a SIM card from, say Verizon into the phone, it will theoretically not be able to make calls or send and receive messages. No such restriction is present on an unlocked phone.