Ill have to agree that Waze is a good one. Someone else mentioned it's only good if others are using it. Not entirely true. It will still route you and get you were you want to go. But if others are using it you have the advantage of being warned about Radar traps, accidents, hazards and the like. Cant go wrong if you ask me.
I also have Navigon as well, but always choose Waze for some reason.
I also have Navigon as well, but always choose Waze for some reason.