The global positioning system (GPS) must be familiar to every user of a smartphone as a way to locate one's position on Earth to within several meters. The constellation of orbiting atomic clocks equipped with radio transmitters allows receivers on Earth to determine their own position by measuring the travel times of radio signals from multiple satellites. A physics laboratory for an upper-level majors course involving GPS signals might be assumed to focus on relativistic effects (either special or general), but this paper demonstrates that the ultra-precise time signal from a GPS receiver can be used for a variety of data collection purposes.