I agree with redundancy. That is why I carry a backup power pack to charge my cell phone if needed. If my phone completely crashes, I carry my iPad mini as a backup. Both have the maps downloaded.
As far as LAT/LON is concerned, why would triangulation be needed? GPS tells me precisely if I am on the trail I plan to be on, or 50 feet right or left. Can a paper map do that?
Electronics fail. Whip out your $800 phone in the pouring rain, all but a few will fail.
My Garmin GPSMAP 60 can do much more than that. Good luck the 50'+/- in canyons. GPS technology has limitations and with phones, even more so. I have been using one more than ten years. It can't sample all that swell.
The wilderness is about what can happen. How's that mini work in the rain?
