Garmin is a world leader in GPS products and technology. In 2016 they acquired DeLorme, and added the popular inReach Satellite Communication and Navigation products to the Garmin family.
Garmin satellite communicators are extremely popular for use in sailplanes. They communicate through the IRIDIUM satellite network - so you are never out of reach. They are used to send GPS position and altitude tracking updates at regular intervals and display your position and altitude on tracking web sites - so your friends can follow your flight. Of course, the tracking could come in very handy in an emergency. Likewise the ability to send and receive emails and text messages could be very important in an emergency. Several preset messages can be sent with a few button presses to send messages such as, "Still Flying", "Landed-out - Fine, but need a retrieve", "Done Flying - Home Safe". Emergency rescue services can also be called - if necessary.
Affordable, Flexible Satellite Airtime Plans