AirPlay 2 was first announced at WWDC in 2017. Unfortunately, the feature did not ship with iOS 11. We then expected it to ship with the HomePod but despite the delayed 2018 launch it still has not arrived. With the appearance of AirPlay 2 in iOS 11.3 betas, we were hopeful that a release was just around the corner; however, now that's its been pulled, its timeline is unclear.
Apple's HomePod page says that AirPlay 2 is 'Coming Later This Year'.
When you add HomePod to more than one room, the speakers communicate with each other through AirPlay 2. Play the same music everywhere or play different songs in different rooms. You can also control any other AirPlay 2–compatible speakers.
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