New week, new iOS 11.4 beta.
Apple today released iOS 11.4 beta 4 to developers. If you're a dev, you can grab this update by going into Settings > General > Software Update on your iOS device. You can also get it from Apple's Developer Center on the web.
The iOS 11.4 beta includes new features like Messages on iCloud, which lets you sync your iMessages across your iOS devices. It also includes AirPlay 2, which has new features like the ability to play the same audio in multiple rooms on all devices.
Apple hasn't said when it will release iOS 11.4 to the public. With WWDC 2018 one month away, perhaps we'll see the iOS 11.4 launch around that same time.
Also released today is watchOS 4.3.1 beta 4. There haven't been any major new features found in this update yet, suggesting that it may be focused on fixing bugs and improving performance.