GPS airtime is a free app that allows you to use the phone in airplane mode. Although it helps to have some cell service. I have used it for two years and have not gotten lost with it but I still have trust issues when out of cell service but so I throw the garmin in for peace of mind. You can also create a waypoint with the app and snap a picture of the place to mark as your waypoint which is awesome. Seeing I always have my phone on me this is a great app to have in the woods. You can download topo and aerial photos to use a reference.
