Nextel phones really annoy me with that walky-talky BLeeeEEEP
Not only that, but that technology (iDEN) is getting old. Apparently, Sprint's trying to get all their Nextel customers to their CDMA/EvDO.
I don't know about this SIM card thing you are talking about.
K, let me fill you in:
>There are three main cell technologies in the world: GSM (Global System for Mobile Communications), which is used by about 80% of mobile phones. Then, there's CDMA (Code Division Multiple Acccess), which is essentially used by Sprint, Verizon, Alltell, Cricket, US Cellular, and MetroPCS. Finally, there's iDEN, which is used by Nextel, and that's about it.
>So, GSM is the biggest in the world, and at&t and T-Mobile use it here, btw. Beneath the battery of GSM phones is a SIM card. It tells the phone which signals to pick up, what your phone number is, and even your address book. It's about the size of a quarter. You can effortlessly move your SIM to another phone and all your network settings, tele number, and phone book is retained.
(Note to fellow phone geeks: I simplified this a lot, I know. So don't try and correct me!

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