How does that mean, then? Unlocking a GSM phone lets you use your phone anywhere in the world with any GSM service. For simple and instant service you simply insert the SIM card into the phone.
GSM is one form of digital technology and does not support CDMA, TDMA or iDEN. A SIM card (subscriber identity module) is a disposable identification card and it has a specific serial number representing you to the cellular provider. No-one is directly connected to a GSM network. Which means you can put your SIM into any phone that is compatible and that phone will now function as yours. This recognizes your handset and not your SIM. But now you can easily switch providers without switching phones unless the provider has its phones configured or “locked” to operate with their company’s provided SIMs only.Link Reasons You Need to Unlock Your Smartphone | Latest World News – Breaking News & Top Stories
You may either use a phone in the United States with either T-Mobile or AT&T, the only existing wireless GSM service. If you’re flying abroad you can change your SIM card to a foreign one.
Getting service to an unlocked phone is a fairly simple operation. First order and sign up for service either in a T-Mobile or AT&T store, or on the website of the company. It’s pretty easy, just place it in the phone and start making calls after you have your SIM card.
How to test if your phone is unlocked or not? It’s as simple as slipping a SIM card into your phone from another phone with an account from a different wireless provider. If the other phone number works and displays then the phone is unlocked. If you get an error message or it is not going to work then the phone is locked.
Please note, however, that in order to browse the web; you will need to ensure that your handset is equipped with Internet settings that are unique to either AT&T or T-Mobile. The carrier can provide you with the settings, or you can also find them on the carrier’s website.
Why would you like your Wireless Phone to unlock? You want to change your current US wireless provider, and retain your phone. You changed your provider and got a new phone, but if you encounter issues, you want to use the other as a backup by swapping the SIM.
You are going to fly abroad and you don’t want to pay the higher roaming rates globally.