Do you want to replace that aging phone of yesteryear that's still stuck in the Stone Age?

This guide will try to answer some frequently asked questions that prospective buyers have when shopping for a GSM phone on eBay. We'll cover GSM frequencies, locked/unlocked phones, used handsets, and deciding on which features are right for you.

Brought to you by cang87 (phonematchup.com).

So What's GSM?

GSM is the most widely used wireless communication standard in the world.

Some of GSM's advantages include SIM cards, or small chips that store network information and allow you to switch phones with ease, a garden variety of available cell phones on the market (eBay and elsewhere), and the ability to make and receive calls anywhere in the world.

The two largest GSM service providers in the USA are AT&T (formerly Cingular) and T-Mobile.

GSM Bands and Frequencies

When browsing ebay phone listings, you might stumble across a cryptic line that sounds something like: "GSM 850/900/1800/1900 mhz." GSM phones use different parts of the radio spectrum, called "bands" or "frequencies," to communicate with the service provider's network. These are measured in megahertz (mhz).

There are 4 GSM bands in the world, with only 2 used in the USA: 850 and 1900 mhz.

T-Mobile only supports the 1900 band, while AT&T supports the 850 and 1900 bands. This means that, if you purchase a tri-band phone (900/1800/1900) for use with the AT&T network, you will probably not be getting the best reception or connection.

So what's the best way to deal with these weird frequencies? Buy a quad-band phone. This will include all four frequencies, so you won't have a problem using your mobile phone anywhere in the world. And you'll definitely have the USA covered.

Unlocked vs. Locked Phones

Cell phones that are sold by a service provider (AT&T, T-Mobile, etc) are usually <b>locked</b>. This means that the phone will only make calls when the company's SIM card is inserted.

There are several ways to remedy this: you can try to ask your provider for what's called an <b>unlocked code</b>, or you can just simply purchase an unlocked phone without having to deal with the potential hassle. Some sellers on ebay provide unlocking services, but this usually requires a large fee.

Used? Or New?

Used phones can provide a nice discount to a completely new handset, but with all used products, there's a tradeoff. And the biggest tradeoff is the battery. Lithium-ion batteries, most commonly used in cell phones, have a short life span - only 1-2 years. It doesn't matter if the battery has been charged or not - its charge will decline either way.

To counter this, you should always ask a seller how old a used phone is, and what the life timer is on the phone. The life timer is the how many minutes have been spent on calls, and is a good indicator of raw usage. Not all phones have life timers, however.

Remember, official phone batteries aren't cheap, so you want to get a phone that's been used for the shortest amount of time.

Choosing Features and Other Fun Stuff

This, of course, depends on just how much you're willing to spend.

At the bare minimum, you should find a cell phone that has a speakerphone and good battery life (at least 4 hours). Beyond that, you're only limited to your budget and how you intend to use your phone: some of the most expensive phones feature a built-in GPS, Wi-Fi, touch-screens (Apple iPhone, anyone?), DVD-quality video recording, - the list just goes on and on.

Find a phone with the features you need, and not necessarily the phone that has everything.

Summary

To summarize what's been said in a couple of easy-to-read bullet points:

1. In the USA, GSM applies to users on AT&T and T-Mobile networks (and some smaller companies)
2. Get a quad-band, unlocked cell phone if possible, so you can use it anywhere in the world
3. If buying used, find out how long the phone's been in use before making a buying decision
4. When it comes to features, pay for what you need - you probably won't use the other features
   

I hope you've enjoyed this little handy guide to purchasing a GSM phone. Even better, I hope it actually proves useful in your search to find a better phone.

Happy shopping!

cang87
phonematchup.com