From https://en.wikipedia.org/wiki/GPS#Timekeeping :
GPS time is theoretically accurate to about 14 nanoseconds. However, most receivers lose accuracy in the interpretation of the signals and are only accurate to 100 nanoseconds.
GPS time is theoretically accurate to about 14 nanoseconds. However, most receivers lose accuracy in the interpretation of the signals and are only accurate to 100 nanoseconds.
Mobile phones use CDMA stuff to sync their clocks, not GPS
NITZ is terrible. You only get one-second accuracy, a GMT offset, and a DST flag, and they can all be wrong at the whim of someone at the phone company.