This is not what the anybody was remotely talking about, but I am feeling pedantic, and I thought it a fun fact. GPS native coordinates are actually a 3d Cartesian grid, however polar coordinates are so much more convenient to us living as we are on the surface of a sphere, I don't think anything outside of the deep internals of a gps receiver use the raw ecef coordinate system.

https://www.e-education.psu.edu/geog862/node/1793