> Regular GPS precision due to ionosphere changes is too low.
... for single-frequency receivers. Military receivers have been dual-frequency for a long time. GPS L2C's rollout is pretty slow (and L5 is even farther behind), but Galileo and BeiDou are both fully operational with dual-frequency civil signals right now. All dual-frequency receivers can naturally cancel out the effect of the ionosphere. That's part of why some smartphone baseband chips are coming out with L5 capability: GPS L5, Galileo E5A, and BeiDou B2A all operate in the same spectrum.