http://www.horizonsunlimited.com/hubb/travellers-advisories-safety-security-road/gps-
 

I used Spot messenger in my Iceland ride last summer.
I was alone on that trip, so friends and family were able to follow my progress and also they could see if I stayed long time on one place.
At least they felt much more relaxed when they saw dot moving hour after hour :thumbup1:

I also sent "everything ok" message to predefined numbers after each day (by using spot messenger), so that they would know that I stopped for the night.