I too recommend the Delorme inreach. As Tiger and others said, it can function as its own hotspot if you wish, and the breadcrumbs uploading is a useful safety feature in itself if you have prearranged instructions with somebody watching the breadcrumbs.
The SOS button goes directly to a professional emergency service that is trained to react appropriately and refer your emergency to a local responder. I am aware of at least one situation in the Sierra where this was put into action. Unfortunately it became a recovery operation, but with the Delorme service acting as an intermediary the remaining members of the party did not risk further injury themselves trying to get help, and remained in touch with Inyo Sheriffs.
I have the inreach SE (yellow facia). This has all the location and communication functions, however there is no navigation interface and the GPS will only display current location. The inreach explorer (orange facia) will additionally function as a GPS navigator, although not a very good one. For a great wrist-mount navigator (only), try the Garmin Fortrex 401.