In iOS 11 was added the function “Emergency call” which will help users to quickly and simply call the helpdesk, but it is also a way to quickly disable Touch ID.
Emergency call is activated, if you press the power key 5 times in a row. A screen will appear which prompts you to power off the device to look at your medical records, call emergency, and cancel the menu.
If you press the power key 5 times, and then click “Cancel”, the mobile will disable Touch ID and will need to enter the password (after that, the fingerprint scanner will work).
This is a handy hidden feature that can save a life. Suppose that after calling the rescue services, the offender requires to quickly unlock the phone, but without a password it can be done.
The feature will be available to all iOS users 11. Now you can install the beta version of the system (at your own risk, because the firmware is still unstable), and the final version will appear in September of this year.