https://arstechnica.com/gadgets/2022/03/ios-15-4-and-macos-12-3-are-here-with-universal-control-and-more/

Today, Apple pushed out the public releases of all its operating systems, including iOS/iPadOS, macOS, watchOS, and tvOS. These releases include new features across all platforms, not just bug fixes or security updates.

As usual, the iOS and iPad update (iOS and iPadOS 15.4) is the most major in terms of number and breadth of changes. The two biggest new features are arguably Universal Control support for the iPad and the ability to use Face ID while wearing a protective face mask.