The iPhone GPS is absolutely worthless. Well, walking it for sure is.
Downtown Dallas for a convention/meeting thing. Was missing some flyers, so I got the nearest Kinko's to print me up some. Said it was 1/3 mile away. So despite the fact that it was about to rain, I walked there.
GPS said "turn right." I turned right. It said walk 900 feet. I did. It said turn left. It said this, that, kept calling out street names that didn't exist but kept telling me to keep going. Then it started to rain.
I finally quit listening, turned it off and went to the other map thing. Turns out iPhone GPS had taken me 16 blocks in the wrong direction. So I had to walk all the way back in the rain to get my stuff that turned out to be one left turn and a block and a half from where I started.
Awesome.