With less than a week before new major iOS is going to be presented Apple provides iOS 16 adoption statistics.
90% of all devices introduced in the last four years use iOS 16.
81% of all devices use iOS 16.
76% of all devices introduced in the last four years use iPadOS 16.
71% of all devices use iPadOS 16.Apple Developer
Adoption grew quite significantly since beginning of the year.
Apple Developer: App Store