...why doesn't anyone report the cost of a "smartphone", including the initial purchase price plus the monthly charges?
I use a Garmin GPSmap60CSx (now considered obsolete by Garmin but very inexpensive on eBay) loaded with free maps from gpsfiledepot.com.
Probably because many of us already have/need the smartphone for our "civilian" lives. (and map reading is becoming something of a lost art.)
When I first scanned this thread, I wondered what had happened to the concept of human-powered generators, but I did some math and realized that Paddlinhal 's powerbank, at full charge, is the energy equivalent to a #150 human climbing a 900 foot tower!