I'm in a city that spans Asia and Europe yet I'm happily using cell phones from Sprint and Verizon Wireless.
I've always thought of Sprint and Verizon as purely domestic carriers, serving only the U.S. market, but that's not the case. Even though most phones from these two popular U.S. carriers are configured to access cellular networks that are totally incompatible with the GSM (Global System for Mobil) networks used in Europe, Australia, parts of Asia, Africa and much of the rest of world, both companies do offer phones that are also capable of accessing GSM networks overseas.
For example, both Verizon and Sprint sell the BlackBerry 8830 World Edition (prices vary by carrier and service plan) while Sprint also has a Samsung Ace Windows Mobile SmartPhone and Verizon the Motorola Z6c World Edition. Each of these phones uses its carrier's CDMA network in North America but is also equipped with GSM SIM cards for use in other countries. Also, most of Verizon's phones, according to the company's Web site, do work in Israel, Brazil, Thailand, South Korea and a few other countries, but not in most of the world. AT&T and T-Mobile use GSM technology that does work in most countries.
SIM stands for "Subscriber Identity Module." All GSM phones have a slot for this tiny card that is required for them to make and receive calls.
From my present vantage point in Turkey and after stops in Majorca, Spain and London earlier this week, I can testify that the Verizon and Sprint phones work great in the places I've visited. Sprint loaned me the Samsung Ace and Verizon provided me with a BlackBerry 8830 for testing, and with both phones I've been able to make local calls as well as international calls to the United States and other countries. Data service also works with full access to e-mail, text messaging and Web browsing. And, perhaps because of Europe and Turkey's extensive GSM network, the sound quality and coverage is as good as or in many cases better than in the United States, even from when I used the phone from a relatively rural areas of Spain and England.
Both Sprint's and Verizon's world BlackBerrys can use the high-speed 3G network in much of the world. Sprint's Ace uses Sprint's high-speed EVDO network in the United States but reverts to somewhat slower networks overseas. Since the only data I'm accessing from here is e-mail, I don't really notice any difference.
And because these are U.S. phones, there is no need to change your number. The regular U.S. phone number rings over here, albeit sometimes in the middle of the night, thanks to the nine-hour time difference.
The only downside is the international roaming charge. It might not be a big deal if you just make a few calls or if you work for a company that pays your bill. But if you're cost-conscious and plan to use the phone a lot from overseas, you had better heed the tariffs. In Spain and in most of Europe the international roaming charge is $1.29 a minute. It's $2.49 a minute here in Turkey and from Ghana and Saudi Arabia. Sprint users who happen to be in Russia, Chad or Kazakhstan could pay as much as $4.99 a minute. There are also data charges for e-mail and text-messaging.
There are ways to beat the system. Sprint's world phones are unlocked, which means you can buy a SIM card in the local country and pay much lower rates. In some cases, it costs as little as 10 or 15 cents a minute for outgoing calls and nothing for incoming calls.
The Verizon phone is locked, but upon request Verizon can provide an unlocked code. There are also third parties and Internet sites that, for a one-time fee, will unlock most but not all locked GSM phones or provide you a code to unlock it yourself. I've used, an independent cell phone dealer to unlock phones that I and family members have used when traveling overseas.
When you're using a SIM card you buy abroad, callers have to dial into the country where you bought the card. So if you bought a SIM card in Spain, callers would have to dial a Spanish phone number to reach you. If you then traveled to France and bought a French SIM card, they would have to dial a French number.
Another option, especially useful if you plan to travel to different countries, is to purchase a global SIM card. Sim4Travel.com and GoSim.com sell cards that can be used in most countries at rates starting at about 60 cents a minute to call back to the United States. It may not be as inexpensive as buying a local SIM card, but you get to use the same number in each country and it's cheaper than paying international roaming rates through your U.S. carrier.
T-Mobile sells phones that can be used both on GSM networks (for a fee of course) and free via WiFi. While in Spain I ran into fellow American journalist John Biggs from Crunchgear (www.crunchgear.com), who let me try out his BlackBerry Pearl 8120 to make a free call back to the States via the hotel's WiFi network. As long as I was close enough to a hotspot, I was able to make and receive free calls. Callers are able to call your regular T-mobile U.S. number and if you answer it from a hotspot it's free, but if you're using the GSM network with T-Mobile's US SIM card, you pay international roaming rates, which vary by country.
Because almost all AT&T phones use GSM, its phones can also be used in Europe at roaming rates comparable to those of Sprint and Verizon. AT&T does offer a $5.99 plan that reduces rates by about 30 percent per minute in Europe.
Istanbul, settled by the Phoenicians in 650 BC, is home to some amazing ancient architecture but when it comes to international communications, its as modern as any place on earth.