iPhone X and 8: What we know about Apple's new phone

Every. Single. Year.

Apple gets international headlines for whatever its latest new (or removed) feature is.

They were among the first to scrap CD drives and they forced everyone to buy new cables and accessories when they suddenly changed the charging port on their iPods, iPhones and iPads.

Their latest MacBook Pros are nicknamed 'donglebooks' because Apple scrapped all of its conventional USB-A ports for more modern USB-C ports.

The problem is you need a stack of dongles to connect all but the most modern devices.

Last year, they got rid of the headphone jack. This year they've ditched the home button in return for a camera that uses your face to unlock your phone.

So here's what we do and don't know

It's supposedly going to be the, "future of how we unlock our smartphones and protect our sensitive information" according to Apple marketing chief Phil Schiller.

Apple is by no means the first to offer facial recognition on its phones — Samsung tried with its Galaxy S8 earlier this year.

But it was very quickly shown to be insecure, and could be unlocked using a photograph of the phone's owner.

Samsung later acknowledged its facial recognition wasn't intended as a security feature.

In Apple's case, we don't actually know how well it works in the real world because Apple didn't let anyone but its employees show it off.

During the keynote, when Apple's software chief Craig Federighi came onstage for a demo, it failed at first.

Now, while it's probably unfair to suggest that's indicative of the product itself, when you're getting rid of the phone's home button and this is the alternative, it needs to be flawless.

Here's how the iPhone X is supposed to work

A projector paints 30,000 invisible infrared dots that create reference points and a pattern that an infrared camera detects.

It runs this through a neural network — essentially an on-board AI system that has been trained to detect faces.

Apple says its engineers used 1 billion images to teach its network to recognise visual patterns within faces that correlate with features like eyes and lips.

The result is a mathematical model of your face which can be used like a password.

Apple says there's a 1-in-1 million chance of it being fooled — far better than the 1-in-50,000 chance of its existing fingerprint sensor.

But if you've got an identical twin, the chances of beating the system are much higher.

"So if you have an evil twin you really need to protect your passcode or your sensitive data with a passcode," Phil Schiller said.

And if you're thinking of a Nicholas Cage/John Travolta Face Off-style face swap, Apple said it had tested its system with professional mask makers in Hollywood.

However, it didn't say how successful or otherwise those faces were at beating Face ID.

So how secure is this?

Apple acknowledges no system is perfect — and there are a lot of questions that we don't know the answers to about Face ID.

Until it gets into the hands of the public, we probably won't find out either.

Apple says its facial-recognition data is stored in a secure, separate area of the device.

All of the neural network processing is done on the device, so it's not transmitted to the cloud for example.

Contrast that with the FaceApp. Remember that hugely popular phone app that made you look older, younger or hotter?

That too uses neural networks, but uploads your information to FaceApp's servers for processing.

In April, we highlighted concerns from privacy experts about the app, because it wasn't clear where your information ultimately ended up or for how long it was kept.

And if you've been overseas recently…

Authorities probably already have your biometric information.

If you used the Smart Gate passport processing system, that takes a photograph of your face and compares it to your passport.