What is GSM?
GSM (Global System for Mobile Communications) is the world's predominant mobile phone standard, first adopted in Europe and then quickly spreading throughout Asia, Africa and the Pacific Rim (Australia, N. Zealand, etc.). GSM enables the same cell phone to work in London, Johannesburg, Beijing, Sydney and elsewhere.

The United States however, did not standardize GSM as a part of it's infrastructure, instead leaving the development of cellular service to competing wire carriers which created whatever standard they wished including CDMA and TDMA. Only recently has the US aggressively embraced the GSM standard.

Carriers such as T-Mobile, Cingular and AT&T are now providing GSM service in the majority of the markets they serve. However, the GSM standard that we use in the US and Canada is not always compatible overseas. This explains why many US travelers have difficulty getting wireless coverage overseas without paying $1- $4 /minute.

What is a SIM card?
The SIM (Subscriber Identity Module) card also known as a "smart chip" is basically the "brain" of the phone, providing cellular service as well as many other functions including call log, voice mail and SMS and GPRS (internet connection standards). SIM cards are the size of a credit card but they have a pop-out chip about the size of a postage stamp which fits into all modern GSM phones. The smart chip is embedded with circuitry and when inserted into a GSM mobile phone provides wireless phone service on a particular GSM network. SIM cards are usually available prepaid or on a contractual basis.

Is this(SIM card) like a calling card?
Not really. You cannot receive a call with a calling card. Calling cards are a bit risky and often provide poor customer service. With the increasing popularity of mobile phones, it is not uncommon to find broken pay phones that go unrepaired by companies that own them.

I currently have a GSM Phone. Will it work overseas?
It is possible, though unlikely, that your current US GSM cell phone will work overseas. Most GSM phones sold in the US are only compatible with the nation-wide operating frequency of 1900 MHz (or the emerging 850MHz band). Overseas services use 900 and/or 1800 MHz frequency standards, which is why we carry only (unlocked) tri-band phones. Most carriers offer global tri-band phones, however they provide them "locked" which is a distinct disadvantage for the consumer.

What is a locked cell phone?
A locked cell phone is one that has been altered in order to use only one particular cellular network. This is often referred to as a service provider lock or "SP lock" for short. All GSM network operators lock the GSM cell phones they sell or offer with their cellular services. This is the hidden cost of the otherwise "free" or heavily-discounted phone you might receive directly from a network operator by signing a service contract. The cost of providing you with a "free" or low cost phone is subsidized over time through more expensive phone rates when you make calls domestically or roaming overseas. In the end, you end up paying much more for your "free" phone and service than you would if you purchased a package. An unlocked phone is therefore one where this software restriction has been removed. Buy Unlocked GSM Phones at these merchants.

How is the cellular coverage in other countries?
Generally speaking, cellular coverage overseas is excellent—much better than average coverage in the US and Canada. Cellular usage is more common overseas than it is in the US and the GSM standard is a higher quality than many of the technologies available domestically. One point to make, however, is that buildings in Europe are sometimes many hundreds of years old. Thus they have much thicker walls than relatively modern US architecture, so if you are indoors and away from a window, you may have difficulty getting reception.

What are PIN and PUK numbers?
Some prepaid SIM cards have a security mechanism in place that requires the subscriber to enter in a PIN (personal identification number) code every time the GSM cell phone is turned on. When a PIN code has been assigned it is important not to forget this code. If you enter the PIN code incorrectly into the phone 3 times in a row then your GSM cell phone will display a Blocked message on its LCD. When this occurs you will then be required to unblock your phone using the PUK code. If you enter the PUK phone incorrectly 10 times in a row you will block your SIM card indefinitely. All phones have a different set of procedures to unblock and you will need to consult your GSM cell phone manual when this occurs. We strongly suggest that if you have the PIN-check feature enabled on your SIM card, that you turn it off. Please consult your phone manual's index under the "security" or "lock" section if unsure how to disable PIN-check.

GSM Buy, Rent and Rate Questions

Is it better to buy or rent the phones?
There is no simple answer for this. If your rental period approaches 2 months, you would be better off buying the phone. Also, if you travel often, it makes sense not having to keep paying for shipping. Renting a phone is a good way to try out our phone and see if you like it. If you decide to keep the rental, you pay no rental fee. You simply forfeit the deposit on the phone. On the other hand, purchasing a phone ensures you will be acquiring an unused handset.

How can I be sure the technology won't become obsolete in the future?
This certainly won't occur in the near future. In fact, this is a relatively new technology in the US that many of the cellular service providers are quickly embracing. Sure, there will always be newer, smaller and "better" cell phones introduced in the future, but the underlying technology powering the service will remain the same. Consider classic cars as an analogy; while they may be less modern, they still get you around because even the oldest vehicles use gasoline for power.

How many minutes come with the SIM card?
The SIM cards usually come with call credits measured in monetary units such as euros rather than increments of time. This is because rate charges for calls vary depending on time of day, destination of the calls and other discounts or charges the carrier may apply. Also, with most GSM carriers providing free incoming calls to the user, the number of minutes on the SIM card could be substantial without the need to add more call credits.

If the SIM card costs $50, do I get $50 worth of talk time?
When you purchase the prepaid SIM card, you are buying the brain that inserts into your GSM cell phone and makes it work. There is always some credit included with new SIM cards, but the amounts vary from country to country. Additional airtime is purchased locally and usually available at or near face value. For example, a 25 Euro voucher will credit your SIM card 25 Euros. The remaining cost for the SIM card is a set-up fee which pays for service on this particular pre-paid account.

What are the calling rates?
Rates vary from country to country whether you are utilizing a country-specific or international SIM card. With the exception of just a few countries, incoming calls (received within-country) for the country-specific SIM cards are always FREE— regardless of origin.

After my trip, could I use the GSM phone I buy in my home cellular plan area?
All of the phones we sell work on the 1900 MHz GSM band, which is the standard in the U.S. While GSM technology is the world standard for mobile phone communications, you may find that your local GSM provider has poor coverage in your area. We at Cellular Abroad cannot determine this information for you. Your best bet is to ask people you know who use a GSM carrier in your area and see what their experience has been. You will also want to check directly with the GSM carrier you want to use to find out their rate plans. Inform them that you will have an unlocked 1900 MHz GSM phone already and find out what's involved in integrating that phone with their service.

GSM Phone Usage

What is my new cell phone number?
Your new cell phone number is a local number for the country pertaining to your SIM card. For example, if you have an Italian SIM card, your number will be a local Italian cell phone number.

Can somebody else use my SIM card?
Anyone can use your card. If you lose your phone with the SIM card inside, you can usually call customer service to deactivate the card so that nobody can use the remaining credit, though they won't be able to issue you a new card. You can also safely lend your phone and SIM card to friends without worrying about incurring any out-of-pocket costs. If they need more talk time, they can simply add some by purchasing a recharge card and using it with your SIM card.

Can I retain my US cellular phone number?
Unfortunately you cannot. We recommend that you leave your overseas cellular number on your domestic voice mail. This way, whoever needs to reach you while you are overseas can still do so. You might be able to forward calls, providing someone can program forwarding for you back in the States. The problem with this is that all wrong numbers, telemarketers and everyone else you don't want to hear from when you're abroad will be able to reach you and that will end up being a nuisance.

Will I have voicemail?
Most GSM phones have voicemail capacity, but it depends on what services are available through the local provider. In almost all cases voicemail is included with your service.

What about text messaging or emails?
These options depend on the local service provider but nowadays they are common features and offered by almost all the overseas carriers.

Can I use multiple SIM cards with my phone?
Since we offer only unlocked phones, you can swap SIM cards as often as you like. However if you are traveling to multiple countries, you might consider that each SIM card has its own unique phone number. In the case of traveling to many countries during one trip, an International SIM card is the optimal choice for many travelers as you keep the same phone number regardless of your position on the globe. Note that you will be roaming when outside the country of origin for the card.

If I run out of call credit, do I buy another SIM card?
NO! Remember, the SIM card is the "brains" of your phone and is rechargeable. Once you have a SIM card all you need to do is add credit for more talk time. Make sure that you do not wait beyond the service life of your SIM card to add more call credit.

How do I add more "talk time" to my SIM card?
In prepaid phone lingo, adding more talk time is known as "recharging" or "topping-up" a SIM card. Recharging a SIM card is as easy as entering a code number into the handset. Recharge voucher cards with recharge codes on them can be purchased at many convenience stores, magazine kiosks and cell phone stores. They are also often found at post offices, train stations and airports. Please note that you can only purchase recharge cards within the country of origin. (If you have a country-specific SIM for Germany, for instance, you can only purchase recharge cards for that SIM card within Germany.)

Will my country-specific SIM card work outside the country of origin?
When you use a country-specific SIM card outside of its home country, this is known as "roaming". While this is often possible to do, there are some problems that make this undesirable for longer side-trips. First of all, the rates are much more expensive for making local and international calls and you don't get free incoming calls. Also, if you run out of credit, you rarely can purchase recharge vouchers outside of the country of origin.

How do I roam with my country-specific SIM card?
Here are some rules-of-thumb for you to use if you plan to roam:

Call customer service for your SIM card carrier to request or confirm that your SIM has roaming capabilities enabled. Roaming with some SIM cards may NOT be possible at all.
Make sure to ask customer service if there are any variations in dialing to or from your number when roaming. (Perhaps the use of a different country code or dialing prefix, etc.)
Ask customer service to provide dialing rates for making and receiving calls when roaming for all scenarios of interest. (Customer service may not be available from the U.S.)
Make sure you have a good guesstimate of how much time you'll use the phone when roaming.
Buy and apply adequate call credits (via recharge vouchers) for use when roaming. You may want to purchase a "backup" recharge voucher to use in case your SIM card runs out of call credits when you are roaming.

How do I know how much call credit I have remaining?
You can always check your remaining call credit. The instructions vary from country to country and are always provided with the SIM cards you purchase through us. Typically you either call a special number or send an SMS message and the carrier answers back with your remaining credit.

Troubleshooting- GSM Phones

I am currently overseas and I charged the phone and inserted the SIM card, but I still can't make any calls. What's wrong?
Generally this problem can be rectified by changing the band the phone is currently operating on. For example, if you are in Europe and the band of your GSM cell phone is set to the 1900 frequency, you will need to reset it to the 900/1800 frequency for it to work properly. Usually you'll know you're using the incorrect frequency if you do not a get a signal on the LCD display of your cell phone. However this is not always the case as it could also mean you are simply not in a good coverage area or indoors. Many European buildings have thicker walls than in the US, so your phone may not work if you are not near a window. If you are roaming and your carrier has different roaming agreements with other carriers, you may be able to improve your coverage by manually switching GSM networks. For details on how to do this, consult your manual.

{Cellular Abroad}

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