How Global Cell Phones Work

Using Global Cell Phones

The basics of using a GSM cell phone are the same in any country. Most people pay for their calls using a pre-paid SIM card. You buy the card with a certain number of minutes and then you can refill it (or "top it off") whenever your minutes get low. You can even set up your account to automatically buy more airtime with a credit card each time your minutes dip below a certain level.

­If you own a tri-band or quad-band GSM phone, then you can travel with the confidence that your phone will work in most GSM networks around the world. This allows you to keep your home phone number as you travel. The downside is that you'll have to pay international roaming fees, which can add up quickly.

Another option we've mentioned is to purchase a local SIM card when you travel. International SIM cards run about $20 apiece. This is a good solution if you travel often and mostly to the same two or three destinations. It's also a good solution if you're going to be staying in a single international destination for longer than a month.

The advantage of a local SIM card is that you don't have to pay international roaming fees. The disadvantage is that you'll have a different phone number with each new SIM card that you buy. This could make it hard for people back home to get in touch with you. You'll also need to re-enter all of your contacts if they're not stored on your phone.

Several companies offer what they call international cell phones or global cell phones. These are a good option for frequent travelers who rarely stay in a single destination for a long time.

Global cell phones are usually tri-band or quad-band phones loaded with a special international SIM card. These international SIM cards offer the advantage of a single phone number without expensive international roaming charges. The rates you pay per minute depend on where you are and where you're calling. Some international SIM cards offer rates of 50 cents a minute where the same call would cost you $1.69 a minute in international roaming charges.

Even if you only travel internationally every couple of years, a global cell phone could be a good investment. There are companies selling global cell phones for as little as $40. For the cost of two SIM cards, you'll have a cell phone with a single lifetime phone number that you can load with minutes when you need them. When you don't need it, you can just put it in the drawer next to your passport and wait for the next trip.

For lots more information about cell phones and travel gadgets, call up the links below.

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