I'll take a look at the GLO but
1. Over recent years I've become increasingly committed to the 'one device for all purposes' camp. Even leaving my Canon IXUS 220 HS at home now.
2. Even walks (hikes) of 10-12 miles, at leisurely pace with frequent stops, often discharge the iPhone 6S+. Bluetooth is a heavy power consumer. What's your practical experience?
I saw your comment in that linked thread about the iPhone capturing several trackpoints per second. I'm fairly sure I recall reading elsewhere that the rate was "1 per sec". Can't find my source now.
That apart, what do think about my tenative conclusions earlier that accuracy decreases as trackpoint rate increases? Not only altitude (which I've almost given up on) but distance too, albeit to a lesser degree?
Terry Pinnell, East Grinstead, UK