Just found a couple apps for iPhones and Android based phones that sound like a must have for any one going out in the back country. IhikeGPS for iPhone and Backcountry Navigator Pro for Android. I tried the Ihike on my iPhone today and it worked great. Best thing about these is they work off your phones GPS signal so they work even if you loose cell service. Both do TOPO maps . For less than $10.00 they are a good safety measure if you ever need it..FWIW.