new iphone 3G has some new cool features such as 3G and GPS; however, its sadly true that you cant use any other provider rather than AT&T. Why? Because ATT is the only provider that supports 3G throughout the USA. Allow me to support my statement. I believe you guys all know that iphone using a simcard and only working under either AT&T or T-Mobile network. You can go on T-Mobile and search 3G, it says that T-Mobile 3G Network only available in NewYork City and they are working on …