https://www.cnet.com/news/ios-12-is-coming-sept-17/

The company also announced that software updates for its HomePod smart speaker and Apple TV will be released on Sept. 17 and that MacOS Mojave will be released on Sept. 24. The HomePod update will enable multiroom audio via AirPlay 2 and let you search for songs by lyrics, set multiple timers, make and receive calls and ping and locate other Apple devices in your home. TVOS will get support for Dolby Atmos 4K. 

We already know from our time with the beta that iOS 12 focuses primarily on improving the performance across Apple's iOS device lineup -- making iPhones and iPads faster, smoother, more secure and less buggy. That noted, there's no shortage of new features and enhancements including applications that leverage AR, tools that track screen time, Memojis, Siri Shortcuts and better notification management.