What is the difference between an locked GSM phones and an unlocked one?

The new Cingular 8525 (Pocket PC) is sold in the US with certain features locked. The same phone known as HTC Hermes or HTC TyTN is sold in other countries as unlocked. What features are locked in the Cingular phone and if I get the unlocked HTC one from overseas, can I use these features in the US without paying the extra to Cingular?

What is Locked phone?

When you buy a cell phone a with some services provider such as T-mobile, Cingular, O2, Vodafone... They'll locked these phone with their networks. It mean you can not use this phone with networks other than the networks you currently locked to.

For example : you have a NOKIA 8800 locked to t-mobile so you can only use this phone with t-mobile services, can't use it with cingular, roger, fido or other networks

How to Unlock my phone to use with other networks provider ?

You can call customer services of your networks provider ask for unlock code if you currently on contract with them over 90days.

Most of old regular phone models ( nokia, samsung, motorola, nec, vitel, sony ericsson ) can unlock for free with a "unlock code calculator software" . You can download it at www.nokiafree.org

Some models: new, not popular or special case can't unlock by this software and must be unlock by special unlock code or software.

Once the mobile phone is unlocked, you can start using it on any cellular network worldwide without any restrictions and save money on roaming charges. You can also use two simcards in the same phone besides the fact that the resale value of the phone is increased The phone carrier gives you the features more convenient for you according with what you are paying, certain features are locked by the company and only could be open with their software, however some hackers can open them too, same phone in different country may have all the features open..? locked and unlocked doesnt refer to the phone programs it refers to the phone itself. a locked phone can only be used with the carrier you bought it from the unlocked phone can be used with any carrier as long as that carrier has the means to activate it. if you plan on buying over seas your best bet is an unlocked phone but there is still no gaurantee that it will work in the states you need to call the cell phone companys and see if they support the phone you want then you will be good to go

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