Can you rapidly force your iPhone to require your passcode or password to unlock? Absolutely — with iOS 11.

Touch ID is an incredible convenience that lets you unlock your iPhone with your fingerprint. Face ID, a facial recognition feature for iPhone X, lets you use your face to unlock your iPhone. But there will come times when you need security more than convenience. For example, when you're traveling through a sketchy area, crossing a border into a region you don't trust, or approached by people or agencies that may not respect your right to privacy. Previously, you had to reboot your iPhone to quickly force it to require your passcode or password for unlock. With iOS 11, though, there's an even quicker way. Here's how!

Note: This feature is currently iPhone only. Hopefully Apple will bring it to iPad as well.

Apple occasionally offers updates to iOS, watchOS, tvOS, and macOS as closed developer previews or public betas for iPhone, iPad, Apple TV and Mac (sadly, no public beta for the Apple Watch). While the betas contain new features, they also contain pre-release bugs that can prevent the normal use of your iPhone, iPad, Apple Watch, Apple TV, or Mac, and are not intended for everyday use on a primary device. That's why we strongly recommend staying away from developer previews unless you need them for software development, and using the public betas with caution. If you depend on your devices, wait for the final release.

How to quickly turn off Touch ID and Face ID on your iPhone

When Apple brought the SOS feature from Apple Watch to iOS, the company added a "bonus" feature: immediately, though temporarily, forcing a passcode or password to unlock.

  • Click the Sleep/Wake (On/Off) button five times in succession.

That's it. The Power Off/SOS screen will appear, and you'll have to enter your password or passcode to get back into your iPhone.

According to an email response Twitter user Keith Krimbel received from Craig Federighi, you can also grip the buttons on both sides of the iPhone X before handing it over, and that will temporarily disable Face ID.

Why you might want to quickly kill Touch ID or Face ID on your iPhone

Most of the time Touch ID is the easiest and most convenient way to unlock your iPhone and get access to all your apps and data. When iPhone X hits, Face ID will be another quick and convenient method for unlocking your iPhone. But it can also make it easy and convenient for someone else, ranging from friends, family, and roommates to criminals to government agents to get into your phone as well.

If you fall asleep, get drunk or drugged, or are otherwise rendered incapacitated or unconscious, anyone in the same room with you could touch your iPhone to your finger to unlock it. That includes roommates or dates you don't trust.

If you're arrested, detained, held captive, or otherwise forcibly confined, anyone near you can force your finger onto the Touch ID sensor and unlock your iPhone. Although Face ID can require attention (your eyes and face looking at your iPhone) to unlock, some are worried that they'll be forced to look at their iPhone X.

Most of the time none of us have to worry about those kinds of ""nightmare" scenarios, but we should all still be aware of them.

When you might want to quickly kill Touch ID or Face ID on your iPhone

Just because you can quickly force your iPhone to require your passcode or password doesn't mean you should. The vast majority of the time, in fact, you're going to want to keep Touch ID and Face ID up and running.

You only want to consider disabling these convenient authentication methods when you're going into an area where you're not sure about your personal privacy rights or safety being respected.

For example, if you're crossing a border into a country or region where you think your device or data might be subject to search or seizure, when you're traveling alone in an area where you think you might be accosted, or when you're going to fall asleep with people you don't entirely trust.

In other words, if you think there's a chance someone will try to put your finger on the Touch ID sensor without your permission and approval or force you to unlock your iPhone X with your face, hit the kill switch and remove that possibility.

Any Touch ID or Face ID questions?

If you have any questions about Touch ID or Face ID, drop them in the comments below!