Question

What do GPS devices do?

Answer 1

GPS unit sends a signal to a satellite, and that satellite sends a signal back, pin-pointing your position on earth it helps you find where you are at or a location

Answer 2

GPS devices help you track where you are and how you will get to your destination. IF you go off course, it will also help you get back on course, or search for another route to the same destination. It basically tells you where you are, how to get to your destination, etc etc.

hope this helps