International Cell Phones

Compatibility is an important consideration

One factor that might further sway your decision on a cell phone plan is international compatibility. Cellular companies in the U.S. use two main proprietary networks for their cell phone service, which means that a cell phone made to work with Verizon's CDMA network will not work on a GSM network, such as those supported by T-Mobile and AT&T. This could be important if you travel overseas and would like to take your cell phone with you. Most European, African and Asian cell phones work on GSM networks. Be aware that American GSM phones and foreign GSM phones work on different frequencies, so you will need a tri- or quad-band world phone that operates on multiple frequencies. Once you're overseas, you can swap your American SIM card for the other country's SIM card. (The SIM card is the little chip installed in your phone, usually under the battery.) SIM cards can be purchased at stores abroad or online before you leave. See our Useful Links section for more information.

In order to swap SIM cards, you will have to ask your cell phone service carrier to unlock your phone, allowing your phone to send signals on a different frequency. American companies will unlock phones for customers, but reluctantly, and usually only after you have been a subscriber for a set period of time. Make sure that you get a password to enter when you place the new SIM card in the phone, as it will not work without the password. Note that this does not mean that while you are traveling you will not be paying your monthly contract fees.

The advantage of switching SIM cards is that a local SIM card gives you a local phone number, making in-country calls inexpensive (avoiding very high roaming fees). And incoming calls (even international calls) are free to you in many countries. However, CNET warns that voicemail messages can cost more than at home.

Unfortunately, neither of the GSM carriers -- AT&T and T-Mobile -- impresses U.S. reviewers as much as Verizon Wireless. T-Mobile offers good value and strong customer service, but subpar call quality and slow 3G and 4G data speeds drag it down in reviews. AT&T wins 3G data-speed tests, but it drags the bottom in almost every other way -- prices, call quality, coverage and customer service.

Top-rated Verizon does offer an option for international travelers. Because most of Verizon's cell phones do not work overseas, Verizon offers hybrid CDMA/GSM phones, ranging from the Droid 2 Global (*Est. $200 with two-year contract) smartphone to the Verizon Wireless Escapade (*Est. $30 with two-year-contract and online discount) flip phone. Although this would enable you to use the same phone on a Verizon CDMA network in the U.S. and on a GSM network abroad, you are locked into a two-year contract and will need to add Verizon's international phone plan to your existing service.

Of course, none of this is simple -- or cheap, says Catharine Hamm of the Los Angeles Times. "Carrier pigeon? Smoke signals? Message in a bottle? All are simpler and clearer than the answers about using cellphones in Europe," Hamm says. You might just want to buy a prepaid phone when you get to your destination -- about $25 for a locked phone that will work in one country, or "double that or more" for an unlocked one that will let you change the SIM card for each country.

You can also check out web-based companies like Unlock123.com, which will unlock Nokia phones for free (for phones that can be unlocked with a code) or $23 (for phones that need a new SIM card). TheTravelInsider.info will do the same thing for most Nokia phones, along with many GSM phones including Samsung, Siemens, Sony Ericsson, Motorola, LG, BlackBerry and Treo, as well as the Apple iPhone. Prices range from $5 to $30. The 2006 Digital Millennium Copyright Act has made it legal for individuals to unlock cell phones for personal use.