The iOS 12 security guide [PDF] is now available. This is the first time Apple has published a security guide so quickly after an iOS launch. It covers things like Siri Suggestions, Shortcuts, Screen Time, Password AutoFill, and more.
iOS 12 Security Guide
Another interesting tidbit: Screen Time is protected using CloudKit’s end-to-end encryption to protect usage data. This is handy because the feature collects detailed information on how you use your device, which could be an attack vector.