Apple is working on development of iOS 12 & will announce some of the new features soon.  However, iOS 11.4 is now available.  One main feature is AirPlay 2 — which provided multiple room speaker support & more advanced sound capabilities.  The new “Messages in iCloud” capability will feature advanced multiple device synchronization.

https://www.cnet.com/news/ios-11-4-arrives-with-airplay-2-messages-icloud-ahead-of-wwdc/

iOS 11.4 arrives with AirPlay 2, Messages in iCloud

Apple drops a little software update ahead of next week’s WWDC, and it’s all about HomePod (and your iMessages).  We’re about a week away from seeing what iOS 12 will be like, but in the meantime the latest version of iOS 11 is now available to download. iOS 11.4 is here, bringing two overdue features promised last year: AirPlay 2 and iMessages in iCloud.

AirPlay 2 is all about multiroom audio, and it also brings stereo dual-HomePod music playback to HomePods. AirPlay 2 will also work on Apple TV, and can be controlled with iPhones and iPads.

But another key feature in iOS is the long-expected addition of Messages in iCloud, which syncs across all devices and deletes iMessages across everything, so you won’t get quite as spammed. It also backs up iMessages so that any new device in the account can get old iMessages without restoring a backup.  Messages in iCloud will use end-to-end encryption, and uses cloud storage instead of local storage for message archives and attachments. And it also works with SMS across devices.