Used an older model of the Spot for work a few years back.
It could be set to send a built in an SMS message to a mobile number with the units GPS coordinates (via satellite) if the holder didnt press a button to "Check-In" at whatever interval was set up. We were able to do away with multiple sat phone check-ins per day. From memory it could send SMS or request emergency response based on failed check-ins and/or the holder pressing the SOS button for a few seconds. The web portal for setting it up was straightforward and was good value for money for that application.
It was used 7 days a week for a few years in pretty harsh going, heat, dust, getting dropped and knocked around but didnt miss a beat.
