I've had very good luck this last winter using a Delorme InReach paired with an iPhone. My fiance spent the month of May climbing Cascade volcanoes and I was able to follow her progress from my desk at work using our shared account. There is a built in screen on the InReach that can show map data, waypoints, and tracks but it's small and low res which is why the device is so nice paired with a smart phone. All of the info displays much nicer on the phone using the Delorme app and it has been fairly user friendly after a short learning curve at the beginning. This system isn't cheap but the advantage is two way communication anywhere that I'll be regardless of cell coverage including an SOS button for emergencies. The battery is rechargeable and is claimed to be good for 100 hours. We haven't pushed 100 hours away from the car in the winter with it but based on what we have done in the summer I don't doubt the claim. The phone lasts that long too since it goes to airplane mode plus bluetooth once we're out of the car.
There are cheaper solutions and better stand alone components but I didn't see anything as simple that gave us redundancy, communication, and most importantly "the button" for help.
There are cheaper solutions and better stand alone components but I didn't see anything as simple that gave us redundancy, communication, and most importantly "the button" for help.