Title: Can I Use My iPhone in Europe? | 10Best
Headings: Can I Use My iPhone in Europe?
Can I Use My iPhone in Europe?
Keep connected on your Euro trip
Buying a European SIM card
GSM vs. CDMA phones
Unlocking a phone
Using a European SIM card
International roaming with a U.S. carrier

Content: European SIM cards are often accepted only in GSM phones, though some newer CDMA phones are starting to support them, as well. GSM and CDMA are two different types of network technology. European mobile carriers all use GSM (which requires a SIM card), as do AT&T and T-Mobile in the United States. Verizon and Sprint, on the other hand, use CDMA, so phones bought through those carriers might not use SIM cards. All iPhones use GSM technology, except for a CDMA version of the iPhone 4 manufactured specifically for Verizon and Sprint. Unlocking a phone
To further complicate things, many American carriers "lock" their phones to prevent users from swapping out their services for a cheaper SIM package. Users can unlock their phones through their carrier or via a third party, but if they do so before their contract with the carrier is up, it can void the phone's warranty. Once the phone is unlocked, a new SIM card should slip right in and work like a charm. If a smartphone isn't eligible to be unlocked by its U.S. carrier and its owner doesn't want to go through a third party and jeopardize the warranty, he can pick up a cheap SIM-card compatible smartphone specifically for the trip. Retailers like Walmart and Target sell them.