When Apple released AirPlay back in 2010 it was a revolutionary technology. The idea that you could send audio from one device to another was new and changed things significantly. But it was always a little limited as it's ability to send different audio to different speakers was non existent. Systems such as Sonos took the lead in offering affordable multi-room systems. But AirPlay 2 is here. Apple is pitching its benefits to the HomePod but I think it's going to be more useful for those using other speaker systems.
AirPlay 2 lets you use Siri to direct audio to speakers in different rooms or areas. Or, you can use Control Centre to direct your tunes or podcasts to wherever you taking your ears.
Apple said in a statement that the new functionality will be available on AirPlay 2-enabled speakers when they become available, noting that Bang & Olufsen, Bluesound, Bose, Bowers & Wilkins, Denon, Libratone, Marantz, Marshall, Naim, Pioneer and Sonos will have products on the market that support their new streaming standard.
The other big ticket item, at least according to Apple, is that you'll now be able to create stereo pairs if you have two of their HomePod smart speakers.
As well AirPlay 2, Apple has added support for Messages in iCloud. This does for messages what IMAP does for email. it allows you to synchronise messages across devices. So, if you delete a message on one device, it will disappear on all devices. It also means that when you set up a new device, your messages will appear by synchronisation rather than restoring them from a backup.
The release of iOS 11.4 just a few days before WWDC suggests Apple has something quite big coming and they are clearing the decks by getting this significant announcement out of the way so it doesn't interfere with what they unveil next week. Or, it could be a way of ensuring the embarrassing delays with delivering AirPlay 2, which has been promised since last year, don't bring any bad vibes to what has become Apple's main event each year.