Apple has seeded the second betas of iOS 11.4 and tvOS 11.4 to public testers. Those in Apple’s beta program can install the updates using each platform’s respective over-the-air update mechanism.
From what we’ve seen in the first betas, iOS 11.4 and tvOS 11.4 both include support for AirPlay 2. iOS 11.4 also reintroduces Messages on iCloud, a feature that will enable true cross-device syncing.
We are also expecting these updates to focus on bug fixes and other under-the-hood improvements. If any noteworthy changes pop up in this latest round of betas, we’ll be sure to report back.