I carry both a Garmin Rhino 530 and my Iphone. I have an app on the Iphone called topo maps its only $10 you can download any topo quad in the US and its unlimited. They are shaded relief and store on your phone so they work anywhere you don't have to be in service. It would be the bomb if I had the ability to only turn on the GPS and not wireless currently its all or nothing. When the phone is out of service it will scan constantly for signal which kills your battery. I think the Android phones can independently control that. I would recommend a smart phone over a stand alone GPS more bang for your buck and safety assuming you can get around the battery issue.