the usa systen has 32 of which 24 are in use at any one timeAlso my belief. The USA has (now) about 31 Sats in world orbits, each circles the globe twice a day. Russia has at least 24 (now) in world orbit, each also circles the globe twice a day. As I understand it, virtually all devices being sold now that use GPS, be it phones or drones, utilize both systems.