This week I'll be upgrading to a Samsung Galaxy III and one app I am very interested in is mapping and turn by turn navigation for cycling (day touring mainly). What is the best mapping app available for general navigation? I am not interested in virtual competition, etc. but having elevation information and a few training bells and whistles would be nice. I have used Google Maps for years on my PC but I have heard that there have been recent issues with the mobile version. Is this true? Is there something better? Any I should specifically avoid?
I'm also wondering how much of my data plan will get used up if I'm doing real time turn by turn for say a 6-8 hour trip. I'm completely new to smart phones so please forgive the techno-newb vibe.
One more question: What are the best ways to carry and/or mount the phone while riding?