One great feature of the new iPhone 3G is GPS. It didn't take me too long to figure it out. The feature is used through the Maps application. You simply identify where you are going by typing in the address, then select, “Get Directions" which it will map out the shortest distance. When you are ready to go, select “Start" and the 3G network will locate you on the map using a pulsing blue dot. As you move, so will the dot. It's definitely pretty cool.

I did notice a couple fixes that would make it better. One would be a voice command to prompt the user to turn or when a turn is coming. Another would be to have the map rotate to that you are always traveling up on the screen. Currently, you have to turn your iPhone after you make a directional change if you want to be moving in the same direction as the blue dot.

The commercial for the Instinct says that it has voice command GPS. At this point I would say that is its biggest competitive advantage over the iPhone 3G. It wouldn't take much for the Instinct's GPS to be more responsive than the iPhone's. I noticed that sometimes I would be passing streets that the iPhone GPS displayed I hadn't yet. I would say the feature is definitely useful, however, if I were planning a long road trip I definitely wouldn't trust it to get me there without a few mistakes along the way.