(AP) -- To prepare for a trip to Tuscany, Paul Boffa visited a local Verizon store to learn about options for taking his mobile phone with him.
Boffa, a musician and teacher who lives in Vermont and travels overseas infrequently, quickly learned that staying in touch with home would be more complicated than he'd thought. A salesman told Boffa and his wife, Maya, about service plans that provide international roaming, but said they couldn't use their own phone overseas.
Then the salesman took pity on them and gave them some good advice: "Let me tell you how I do it when I go to Bosnia. Just get a cheap phone and put a new SIM card in it and just use up that card."
And that's what the pair will do.
While almost anyone, anywhere, can log onto the Internet and read e-mail with easily recognizable technology, things aren't nearly as simple when it comes to communicating by voice. U.S. travelers face a bewildering array of options when they plan a trip to another country.
Not all phones will work abroad, and even if yours does, you could end up with some very expensive roaming charges unless you sign up for an international calling plan before you go. Some carriers, like AT&T, can pro-rate an international plan so that it's only in effect for the duration of your trip.
One reason for the complexities is that there are two main cellular technologies: GSM, or global system for multiple communications, and CDMA, or code division multiple access. GSM, used here by AT&T and T-Mobile, is the standard in most of the world. CDMA networks, used here by Verizon and Sprint, are also used in Canada, Latin America and parts of Asia, and roaming options are very limited. GSM phones have SIM cards, portable memory chips that can be switched from one phone to another, while CDMA phones do not.
"When you go to Belgium or Denmark or Germany or Italy or France or Spain or Lichtenstein or Switzerland, everyone has their own rate structures, and they have their own networks," said John Walls, vice president of public affairs for CTIA-The Wireless Association, a wireless phone industry group for the major carriers. "That's why Europeans quite often will load up with three or four different SIM cards to put in their device, so depending on where they are, they'll slot one out and in, because the roaming charge might not be as expensive on one than another. That's the normal relationship that they've accepted."
In contrast, Americans are accustomed to using the same phone everywhere in the U.S.
Christine Moe, an epidemiologist at Emory University in Atlanta who travels frequently for work, uses her Blackberry 8830 World Edition when she's in Europe, where it works well. But in Bolivia, where she also travels frequently, it doesn't work at all, Moe said, so she has purchased a Bolivian cell phone.
"It's very puzzling," said Moe. "My colleagues from Sweden, when they're in Bolivia, their phones work just fine."
Frequent traveler Matt Harris, who runs a venture capital firm in New York City, is headed to vacation in Egypt in November. He has his assistant researching his options for renting a phone here and taking it with him.
But "probably what I'll do, I'll buy a cheap phone in Egypt," said Harris.
It's not hard to buy a local phone abroad, even in poor or developing countries.
Any major Indian city has a cell phone shop on almost every street, said Alx Utterman, a Santa Cruz musician and writer who visits an ashram in the small village of Penukonda in South India a few times a year.
"A place that has electrical appliances and radios and that kind of thing, they always sell cell phones," said Utterman. "You can get a fine, functioning cell phone for $40 or $50 American - a simple phone that does what you need it to do."
Utterman also buys a SIM card, turns off her U.S. phone, and uses only the Indian phone while she's in India. A 1,000-minute SIM card sets Utterman back about $12 U.S., she said.
The drawback to using a locally purchased phone is that you have a new, international phone number, which your contacts back home won't know. And not all SIM cards come with prepaid minutes, so be sure you know what you're buying. You don't want a contract for a temporary phone.
The difficulty and expense of using a mobile phone overseas has led many to Skype, an easy-to-use software that enables phone calls over the Internet. That's what Moe does - using her laptop, which has a camera, to stay in touch with her students and family from hotel rooms or Internet cafes.
"I've used Skype to call Delta to change my ticket," she said. "In the middle of Bolivia I've used Skype to call my family; the laptop has a camera so I can show my family what my room looks like."
Skype, she said, "has revolutionized everything."
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