Quite simple, the answer is no. When consumers see the term ‘unlocked’ in reference to cellular phones, it is most almost certainly being used to describe a GSM phone. To truly understand what an unlocked cell phone is, you need to have a basic knowledge of GSM and CDMA technology.
In the North American markets, and Latin American markets for that matter, GSM and CDMA are the two technologies that the dominant service providers use. What most easily distinguishes one from the other is that GSM carriers require phones that use SIM cards, and CDMA phones do not. Here is a brief breakdown on what technology the dominant carriers in the USA use: T-Mobile, AT&T/Cingular, and Nextel (Not Sprint/Nextel) use GSM technology, and Alltel, Cellular South, US Cellular, Sprint/Nextel, and Verizon use CDMA technology.
Because T-Mobile, AT&T/Cingular, and Nextel use GSM technology, their phones require SIM cards, which are portable memory chips that go into the back of these phones. When you sign up for a service plan with one of these service providers, your account registers to your SIM card and not to the actual phone (which is the case with CDMA phones). This technology allows you to remove, lets say, your T-Mobile SIM card from your T-Mobile phone and place it in any other T-Mobile phone and use that new phone with your account, instantly.
This is where “unlocking” phones comes into play. The phones that are produced for T-Mobile, AT&T/Cingular, and Nextel are programmed to only recognize their own company’s SIM cards. When one of these GSM phones is unlocked, however, it will then recognize any SIM card from pretty much any other GSM carrier. The ability to unlock GSM phones greatly benefits consumers who have service plans with GSM companies. Lets say that T-Mobile makes the same version of your AT&T phone, but the T-Mobile phone has a camera and yours does not. All you need to do is purchase an unlocked T-Mobile version, and you can now use that camera phone with your AT&T service.
GSM technology is arguably the worldwide standard as well, so purchasing an unlocked GSM phone makes world travel very convenient. Lets say that you are a T-Mobile customer with an unlocked cell phone, and you book a vacation to Puerto Vallarta, Mexico. Instead of paying international rate charges for using your phone in Mexico, you can simply purchase a pre-paid SIM card from a Mexican cellular company, like TelCel, and use it with your unlocked phone.
There are some features that work only with a phone designed for a specific carrier, though, so a consumer interested in purchasing an unlocked cell phone should definitely check with their service provider to make sure that the features that the need will work with an unlocked phone.