Since updating to the latest Waze version 3.5.0.0 running on my iPhone 4S with iOS 6.0.1 I also use a TomTom car kit just to dock. I am getting constant crashing when trying to load Waze or after switching to another app and trying to get back to Waze. The previous version never did this.
I have to try reload it 3-5 times before I get it to work.