Phones have already supported QZSS for years. Maybe a decade for Nexus phones and 5 years for iPhone. The constellation is designed to help with some Japan-spe

Phones have already supported QZSS for years. Maybe a decade for Nexus phones and 5 years for iPhone. The constellation is designed to help with some Japan-specific problems. Eg Glonass is optimized for polar environments, not helpful in Japan. For geopolitical reasons, Japan is also not crazy about depending on Russia/China. GPS assumes you'll usually be able to see a satellite when it's at an oblique angle, not helpful in big cities with skyscrapers where oblique birds can cause issues with multipath reflections and all-around bad signal in urban canyons. QZSS does it's best to make sure there's always a satellite above you, not off by the horizon. It plays nice with GPS and has a very precise signal similar to the FAA's WAAS )