grunt0300 asks in the Android Central forums,
ATT vs Verizon?
Just wondering which provider works best in Europe?
AT&T is a GSM carrier, and that means SIM cards. AT&T also uses mostly compatible 3G bands with the continent, so it's easier -- on the surface.
The reality is both AT&T and Verizon lock phones to their network (if you're using an unlocked handset you probably wouldn't be asking this one), meaning they won't work anywhere else. This is simple enough to fix on an AT&T phone, but you'll need to enlist a third party to help, or root and monkey with things a little bit. Verizon is a CDMA carrier, but they do offer world phones that take a SIM card for use outside the U.S. Like an AT&T phone, you'll need to network (or SIM) unlock it to use a pre-paid SIM card in Europe.
Of course both carriers will sell you an international plan, complete with expensive rates and restrictions. Verizon will even rent you a world phone for a couple bucks a day if you need one. It's a matter of how much you're willing to spend for the convenience, and to keep your same phone number. You can walk into the carrier's shop, tell them what you need to do, and they will take care of everything for you, and for a fee.
Our recommendation is to get the SIM unlock and pick up a pre-paid card from a kiosk or machine at the airport. If you're using a travel agent, they can help, too. In this case, unless you already have a Verizon world phone, AT&T is your best bet.
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