There's been a lot of random misinformation about the iPhone 3G floating around out there, like David Pogue's baffling comment that the device's GPS antenna is "too small" to support turn-by-turn directions, and Apple's iPod and iPhone marketing head Greg Joswiak recently sat down with AppScout to clear up some of the confusion.
There are various methods of unlocking a carrier locked iPhone. You must unlock your iPhone device first so that you can use any carrier GSM network on it all around the world without any restrictions. All carrier locked iPhone models can be unlocked easily.