Apple Pay Cash is the biggest new feature in the update. It allows you to easily send money via messages to friends, family and colleagues but sadly is not yet available in Australia.
A little bit, it is one of the more serious issues that Apple has had with macOS. Anybody who has physical access to your Mac or can get to it through via screen sharing, VNC, or remote desktop can gain complete access to the machine.
Face ID replaces Apple's fingerprint tech (Touch ID) to unlock your iPhone and approve certain actions. It takes a little getting used to and you will find yourself going for the non-existent Touch ID button at first.
Cloud storage services sync folders on your computer to the cloud; allowing you to work from a folder across devices. If you accidentally delete a file sometimes these services even have a recovery feature. This of course only works for files that are in the synced folders.
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