You’ll Soon Be Able to Unlock an iPhone with a Mask (Without an Apple Watch)

Now that Apple has gotten a number of critical security fixes out of the way in iOS 15.3, it’s wasting no time getting the next major point release out for testing. The first beta of iOS 15.4 was released to developers yesterday (with a public beta likely coming as soon as today), and we’re already seeing some interesting new features.

In fact, there’s at least one big surprise in iOS 15.4; Apple appears to have come up with a way to allow users to authenticate with Face ID while wearing a mask — without the need for an Apple Watch.

Since the beginning of the COVID-19 pandemic, when many folks suddenly found themselves with the need to mask up in public places, Apple has been taking baby steps to help Face ID accommodate this new reality.

For instance, in the early days Apple tweaked iOS 13.5 to bring up the password prompt much faster, allowing users to get into their iPhones quickly by keying in their passcode when Face ID failed. While this didn’t really make Face ID work any better when wearing a mask, it at least took away some of the frustration of waiting for it to give up just so you could unlock your iPhone the old-fashioned way.

As public agencies called on Apple to improve the situation to help encourage people to keep their masks on, Apple came up with a solution in iOS 14.5 that leveraged the Apple Watch to help verify users. As Apple later explained, this simply handed off authentication to a nearby Apple Watch whenever the iPhone detected someone wearing a mask.

This meant it wasn’t the most secure solution, since anybody wearing a mask could unlock your iPhone using Face ID, as long as your Apple Watch was within range. Apple took several steps to mitigate this, such as notifying you on your wrist as soon as your iPhone was unlocked this way, and ensuring that it only worked when you were actually wearing your Apple Watch in close proximity to your iPhone. It wasn’t entirely foolproof, but in most cases, it was unlikely somebody would be able to get into your iPhone without your knowledge.

Now, a year later, it looks like Apple is preparing to offer an even better solution in iOS 15.4. As anybody installing the iOS 15.4 beta will easily discover, a new Use Face ID With a Mask option is now appearing.

The new setting is basically impossible to miss, as it comes up in an introductory setup screen as soon as you finish updating to the iOS 15.4 beta, offering the option to configure Face ID for use with a mask, and describing it thusly:

Face ID is most accurate when it’s set up for full-face recognition only. To use Face ID while wearing a mask, iPhone can recognize the unique features around the eye area to authenticate.

From that explanation, it sounds as though Apple has managed to tweak its Face ID algorithms to more accurately recognize a person’s upper face area only, basically ignoring that part that is covered with a mask.

This makes the new feature theoretically less secure than normal Face ID, which is likely why it’s an optional setting, but it’s also arguably more secure than last year’s Unlock with Apple Watch option. At the very least, there are pros and cons to each.

As we noted earlier, Unlock with Apple Watch will let anybody wearing a mask unlock your iPhone. In fact, it will sometimes unlock via your Apple Watch when it’s pointed at a wall or a table. Your Apple Watch always needs to be within a few feet, and you’ll get a notification as soon as it happens, but it’s not hard to imagine scenarios where somebody could still unlock your iPhone without your permission or knowledge.

For example, the feature won’t work if the Apple Watch is in sleep mode, but that doesn’t engage automatically if you’re merely taking a nap, and if you’re a deep sleeper, the unlocking notification may not be enough to wake you up. It ultimately comes down to how much you trust the people you live with.

By contrast, the new Use Face ID With a Mask feature still only unlocks your iPhone based on your specific facial features. While it’s certainly possible that somebody else’s face could also be used to unlock your iPhone — Apple admits it’s less accurate than using Face ID without a mask — the person would still have to look enough like you. Unlike the Apple Watch method, this won’t work for just anybody.

Apple also notes in the description that you must be looking at your iPhone to use Face ID while wearing a mask. From our testing, this appears to be the case even if you have the Require Attention for Face ID option switched off.

Wearing Glasses with Face ID

One interesting wrinkle with the new feature is that you’ll need to train Face ID for each pair of glasses you wear regularly — and it also doesn’t support sunglasses at all.

You can enable the Use Face ID With a Mask option either during initial setup or by toggling on the switch under Face ID & Passcode in the Settings app. You’ll have to go through the Face ID scanning routine again, which must be done without wearing a mask.

Once that’s enabled, a new Add Glasses option will appear immediately below the Use Face ID With a Mask switch in the Settings app. Tapping on this will take you through the Face ID recognition process again, but this time with a pair of glasses.

It appears that you’ll need to repeat this for each different pair of glasses that you regularly wear. A note underneath the main Use Face ID With a Mask setting will show how many pairs of glasses you’ve added.

The requirement to add glasses is specific to the new mask-aware Face ID feature. It won’t even appear unless that’s switched on, and it seems to have no bearing on how well a standard Face ID scan (without a mask) recognizes you, with or without glasses.

Our educated guess is that Face ID has little enough to go on when you’re wearing a mask, so a pair of glasses is much more likely to throw it off, causing it to fail to recognize you properly.

From my limited testing of the feature, it appears to work really very reliably in the first beta. I tried a variety of different masks, and even three different pairs of reading glasses, and my iPhone 12 Pro Max recognized me flawlessly and unlocked nearly every single time — as long as I was looking at it, which seems to be a core requirement.

It’s worth noting that the old Apple Watch unlocking feature hasn’t gone away — at least not yet — and the two features will sort of work in tandem. Much like how normal Face ID works, the new mask-aware Face ID feature takes priority, so the Apple Watch will only be used when the iPhone can’t recognize you on its own. In my testing, this happened only when I wasn’t looking right at the iPhone while trying to unlock it.

Of course, the Apple Watch feature can also be toggled off, just like it could before, in which case your iPhone will only unlock if it recognizes the upper part of your face, or at least sees a face that looks very similar.

Naturally, with the feature only just arriving in beta form, Apple hasn’t published any stats on how likely it is that somebody else would look enough like you to fool this new Face ID system, but I couldn’t find anybody in my immediate circle of friends and family who was able to unlock my iPhone — even when wearing a mask.

It’s also probably fair to say that Apple will continue refining this in future betas, but it’s also too early to tell if it will even make the cut for the final iOS 15.4 release. Apple has unveiled new features in past betas that ended up being held off once the public release rolled around. So, we’ll have to wait and see what ultimately comes from this, but so far, it looks very promising.