The problem doesn't pose any real danger, but hasn't yet been patched by Apple

A strange iPhone bug forces iPhones to stop working entirely.

The bizarre issue doesn't appear to pose any immediate threat, and can only be done by someone who has access to the phone – unlike recent, more malicious issues like the ones that allow people to crash phones with just a text message. But it is certainly irritating and seems to work on all versions of iOS, and hasn't yet been fixed by Apple.

The issue forces the iPhone to temporarily become useless. But once time has passed it will fix itself again, allowing the phone to come back to life.

The problem is activated by opening up the Control Center that appears if you slide up from the bottom on any iPhone. If someone then taps at the same time on three of the meu options – like the AirDrop key or the shortcuts to the camera – then the phone will go into shutdown and freeze.

The iPhone will stop working for a while and there appears to be no way of bringing it back to life, showing only the Control Center menu. Eventually, the phone will come back to life and allow people to use it again.

The bug appears to be present even in the iOS 10.3.2 beta, suggesting that Apple hasn't yet worked out a fix.

It isn't clear how the problem originates, though it's likely that it's the phone's inability to deal with the requests from all three buttons. Usually, however, a modern iPhone would just reject those requests, quit the app and start itself up again.

There appears to be no way of avoiding the problem entirely or shielding a phone from it, beyond deactivating the Control Center option entirely. It can be turned off from both the lock screen and within apps from the Control Center options in the settings app – deactivating it on the lock screen means that people will only be able to trigger the problem if they have entered their fingerprint or passcode.