Does GPS require internet?

Generally - no, but if GPS was not active in your device at the moment AstroClock starts, it may take few minutes, depending of signal strength, to get it work because to start calculating the coordinates GPS needs some extra information - precise time, satellites constellation ephemerides (orbit parameters), ionosphere delay (almanac).
All those may be obtained almost instantly via Wi-Fi or mobile provider network, otherwise they will be downloaded directly from satellites with a killing slow speed*.

If you have problems with AstroClock fixing your current position, run some GPS test program like this.

If you see something like this, your device has a GPS problem.



If a test shows that satellites are available and position fixed but AstroClock doesn't recognize your location, contact support.



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* Data rate of the satellite signal is only 50 bit/s