Took along time to scroll through this.
I carry a phone to take pictures. I've used it a couple times to help others.
To answer the OP. How to communicate in areas with no cellular telephone coverage?
There was mention of a satellite tracker called SPOT.
Spot uses the GlobalStar satellite constellation which have a design flaw limiting bidirectional communications.
GlobalStar took many years to bandaid this problem.
I used SPOT devices as emergency beacons for many years on off road motorcycle trips.
There is a better satellite tracker.
Garmin bought a company called Delorme for their InReach satellite tracker technology.
InReach uses the Iridium satellite constellation and is bidirectional.
Meaning you can send text messages to anyone, anytime to anyplace on the planet from anyplace on the planet.
I switched to InReach many years ago.
You can use the tracking service to show you location on an online map so your family can see your progress.
I used this so my family could follow me on the Death Ride and for multi-day MTB trips from CO to UT.
You don't have to use the tracking service to use the global texting service.
The InReach Mini is really small, works stand alone.
Creating a message on the InReach is a bit slow or you can pair it with your phone.
I was camping I Panamint Springs and texted a friend to bring more beer.
I use the InReach for long rides with areas no coverage.
You don't have to.
Happy pedaling
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