[nathan_f77]

I'm pretty sure that many of your concerns could be alleviated with a lifeproof case (rugged and waterproof), the maps.me app (offline maps for iPhone, also supports KMZ hiking trails), and a few 10,000 mAh USB batteries. I use one which typically keeps my phone charged for a few days, with a lot of use.

This is great for relatively small hikes. But if you're going off on a major expedition, then sure, you should probably take the professional radio and Garmin gear, and all the other survival gear people normally bring.

But if you've already got the lifeproof case and extra USB batteries, I think this Beartooth device looks pretty useful.