I use a Garmin inreach - the mini one is a little hard to use on its own because of the small monochrome display, but it pairs to your phone with bluetooth and

I use a Garmin inreach - the mini one is a little hard to use on its own because of the small monochrome display, but it pairs to your phone with bluetooth and has a nice companion app. Also, the EarthMate app has a nice mapping interface which shows things like topographic maps and major trails, and it lets you download maps ahead of time in varying levels of detail for offline use.