The iPhone 3GS is Apple's 2009 upgraded model of their most popular device. The iPhone 3GS is all about speed (hence the "S" in the name). Faster processor, faster video, faster data via HSDPA 7.2 (if your non-AT&T network supports it), and video capture backed by more storage. 3GS gets an upgraded camera with auto-touch-focus and VGA video capture, but the big news is software-related: Voice control, support for software-enhanced dock accessories, remote wipe and "Find my iPhone" features via MobileMe, and more.
Buying a replacement phone will not affect your existing service contract, but are generally more expensive, since they are not being discounted by your carrier.
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Carrier Compatibility
Properly unlocked, this phone should be compatible with:
AT&T - Note! Always confirm compatibility before purchasing.
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