https://wccftech.com/beta-4-of-ios-12-2-watchos-5-2-macos-10-14-4-tvos-12-2-now-available/

Apple has released beta 4 of iOS 12.2, watchOS 5.2, macOS 10.14.4 Mojave and tvOS 12.2. We’ll show you how you can update right now if you’re a developer.

Developers can go ahead and download the fourth beta of Apple’s upcoming software. If you already have iOS 12.2 beta 3 installed then just plug your iPhone or iPad into a power outlet, connect to WiFi, launch Settings > General > Software Update. You’ll see the latest update here for download. Just tap on Download and Install and you’ll be updating your device in no time.