This is our yearly reminder, folks: Unless you're a developer with a secondary iPhone or Mac, we strongly, strongly urge you to consider not installing developer betas on your devices.
It's not because we don't want you to have fun: iOS 12, watchOS 5, tvOS 12, and macOS Mojave have some phenomenal features coming this Fall. But they're beta seeds for a reason: These features are not fully baked, may crash at will, and probably will slow down or crash your third-party applications.
If you're a developer, researcher, or otherwise need the beta on a device for day one, please back up the phone, tablet, or Mac first; preferably, that device should be an auxiliary model you have lying around. (Older iPhone and iPads make great test devices.)
In short: Be smart. The public beta period for iOS 12 and macOS Mojave is coming later in June, and that seed will likely be much more stable. And if you must install the betas, proceed with caution, and ideally do it on a secondary device.
