I dont know anything about the Cell phones but the GPS map combo is nice to use. here is benifits and drawbacks of both
GPS drawbacks needs batteries, is expensive, needs at least 3 satallite signals to triangalate. they can be lost easy. need to know how to work them. can break.
map and compas. need to laminate the maps, need to know how to read the map and compas, be able to walk in a straight line and know how far you have traveled (pace count). compas may break,maps rip, water damage.
the best bet is use all three. map compas and GPS, you always need a map to see what in your area ie: steep dropoffs, rivers. compas to know what direction to orient the map. and the GPS is a nice double check to see your location. or quickly check your distance of travel.
always protect your map, it is your best resource if you are lost you could do without the GPS and compass in an emergancy, as long as you have a few woodsmans skills like finding the North star knowing the sun comes up in the east.
