On the 7th September event, Apple has announced many things alongside iOS 16 and WatchOS 9. This two latest version OS for new phones and wearables. The iOS 16 is for the existing phone and Watch OS 9 for Series 4 or later. Both will releases on 12th September.
iOS 16 and WatchOS 9 announced to release on 12 September
This year iPadOS is not upgrading, it will stay iPadOS 16. On the other hand, iOS 16 and WatchOS 9 for iPhone and Watch already unveiled in the last Apple’s developer conference on June. We should wait more time for iPadOS new upgrade version.
This year iPhone launched three watches. These are, Apple Watch 8, Apple Watch SE and Apple Watch Ultra. It will be adjusted with WatchOS9. If you upgrade your wearables to new this version, you have a iPhone to run new version (WatchOS 9) set up system.
Apple watch will also be launched on 7th September event
Source: (1)