https://arstechnica.com/gadgets/2019/12/the-iphone-11s-u1-chip-necessitates-constant-geolocation-pings-apple-says/

Earlier this week, security reporter Brian Krebs published a story explaining that Apple's latest iPhones (iPhone 11 and iPhone 11 Pro) periodically check the user's location even if the user disables location services individually for each and every app and service in the iPhone's Settings app.