I'm surprised this hasn't been covered yet. Seems like it could be useful especially for gravel and MTB riders. Garmin bought DeLorme and acquired their InReach technology, a SEND. Now there's a smaller version that allows 2-way text messaging and live tracking anywhere on earth, integrates with high-end watches, and has an SOS button to call in the cavalry.
https://www.dcrainmaker.com/2018/05/...th-review.html