GSM Mobile and Cell Phones: What to do if locked

GSM cell phones are designed to work with any service provider. In theory, all you need to do is swap the SIM account card. However, some unscrupulous service providers may ‘lock' the phones, rendering them useless should the user choose to subscribe to another network. They do this by locking your phone's SIM to the phone itself, so no other SIM will work in it. But what if you do want to switch networks? What if you want to leave your old contract and subscribe to a new (and cheaper!) operator, or just switch SIMs to use a local operator's network when you travel abroad?

Phones are naturally unlocked
All GSM cell phones come unlocked in their original conditions. That is, they can be used with any SIM from any cellphone service provider - always assuming, of course, that the cellphone service provider has compatible GSM service on the same frequency bands that the phone can operate on.

Some cell phone service providers electronically 'lock' the phone so that it can only be used with their service. There are obvious reasons why they choose to do this - in particular, to force you to pay what are usually very high roaming charges when you take your phone out of their network and use it elsewhere in the world.

Fortunately, this locking is reversible. With some phones, it is possible to simply enter an unlocking password code into the phone and it is immediately then unlocked. Other phones need to be connected up to a special unlocking data terminal.

What is GSM? Is it different than normal cell phone service? How do I know if I have GSM?
GSM is a type of digital mobile phone service. The more common type of digital mobile phone service in the US is CDMA, but just about every other country in the world uses primarily or only GSM. For you as the user of your phone, there is no difference at all between using a phone on a CDMA system or a phone on a GSM system. Unfortunately, the two different systems are not compatible with each other.

Today, cell phones are made more innovative by applying technologically advanced applications such as GPS or Global Positioning System. Equipped with this remarkable device, cell phones can now operate beyond their basic functions. With the GPS system, cell phones can be used as a tracking device that enables people find the right places or even hunt down a relative or friend on his exact location.The central hub of the system depends on “24 satellites" that move around the earth two times a day. The identification of certain locations is made possible using fully operational devices that includes a series of receivers and satellites.