Apple today released for developers the fifth beta versions of iOS 11.4 (compilation 15F5077a), from macOS High Sierra 10.13.5 (17F70a), from watchOS 4.3.1 (15T5567a) and the tvOS 11.4 (15L5576a).
They arrive exactly one week after the fourth beta and should not bring big news beyond what we already know: Messages on iCloud are again being tested on iOS and macOS, just like the AirPlay 2 protocol. It is worth noting that iOS 11.4 beta 3 hinted that HomePod now also has support for the Calendar app (Calendar). At watchOS, we have a new incompatibility alert for old apps and a long possibility for third-party displays on Apple Watch.
Soon, these new test compilations should also be painted for members of the Apple Beta Software Program with the exception of watchOS, which does not participate in it.