Generally, you use the radio network from mobile phone to cell tower, and then fibre optic to the switches. Sometimes they use microwave line of sight for surface-to-surface connections where fibre doesn't make sense, or is unviable (terrain, distance, cost, difficulty of laying fibre, etc.). It's possible that there could be a satellite connection in the process, but unlikely unless you're on an airplane, a ship, etc.
The GPS on the mobile phone definitely does use satellite (receive only though, no transmit).
13 years on Reddit. I was part of the Great Digg Exodus... now the Great Reddit Exodus.
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