I'm not as young as I used to be so my wife "encouraged" me to get a cell phone to take on any hike that involved being out overnight. Since I'm carrying the weight of the thing I'm trying to find ways to make it useful. I've always had trouble navigating on long, rocky sections of the AT. If I were to load an AT app on my phone could I accurately follow the "track" displayed on the screen to help me navigate the trail route through rocky sections?