Apple today made iOS 11.4 available to the iPhone, iPad, and iPod Touch. The most significant new feature of iOS 11.4 is AirPlay 2, a more advanced version of Apple's wireless audio technology. AirPlay 2 lets people create multi-room wireless audio systems so music and other media can play on different devices in different rooms at the same time. Apple says built-in Control Center and Siri actions make it easy for people to control where the music is playing. AirPlay 2 works natively with Apple's own HomePod speaker. Apple says the HomePod can automatically stream music around the house without requiring users to first manually group them. Apple Music subscribers can ask Sir to play different songs in different rooms or the same song everywhere. Apple said AirPlay 2-enabled speakers are on the way from partners Bang & Olufsen, Bluesound, Bose, Bowers & Wilkins, Denon, Libratone, Marantz, Marshall, Naim, Pioneer and Sonos. Once these device makers add support for AirPlay 2, owners will be able to use Siri to control music on these third-party speakers, too. HomePod owners can turn on support for personal requests, which allow them to send messages, add reminders, check calendar appointments, set timers, play podcasts, and catch up on news, sports, traffic, and the weather. iOS 11.4 also introduces Messages in iCloud. This tool lets people store complete message threads in iCloud for porting to new devices. Once synced, Messages in iCloud brings entire iMessage conversations to users' devices so they always have access to them. The other goal of Messages in iCloud is to free up local space on users' devices, as media embedded in messages is kept online, rather than stored locally on the iPhone.