https://www.techradar.com/news/ios-114-brings-two-long-awaited-features-one-week-ahead-of-ios-12-beta

We're ready to test iOS 12 beta next week at Apple's WWDC 2018 keynote, but first, iOS 11 is getting one last revision thanks to today's iOS 11.4 update.

iOS 11.4 is officially (and finally) bringing Messages in the Cloud and AirPlay 2 to your iPhone and iPad, long-overdue features announced at last year's WWDC event.