Actually, the GPS satellites are not geosynchronous satellites, which would imply orbits at 22,236 miles above sea level for circular orbits. From Earth, only those orbits appear stationary (in equatorial orbit) or at least varying within a relatively small area (if not in equatorial orbit).

The GPS satellites are in Medium Earth Orbit (MEO), around 12,540 miles. The GPS satellites do not hover over one area. They don't have to hover. Each satellite broadcasts its own four dimensional position in spacetime (3 space coordinates and the time, kept by accurate atomic clocks). Based on the calculated time delays from at least 4 satellites, a GPS receiver can uniquely determine the it's position.

See the Wikipedia article on GPS: https://en.wikipedia.org/wiki/Global_Positioning_System

and on geosynchronous orbit:

https://en.wikipedia.org/wiki/Geosynchronous_orbit