If you find yourself in a situation where you might be detained and thereby unable to control interactions with your device, on iPhone you can disable TouchID and FaceID by holding one of the volume buttons and the sleep/wake button simultaneously for a few seconds. This will require you to enter your passcode the next time you want to unlock iPhone. Anyone have similar instructions for Android?
Pressing both should go into a mode where you can swipe to call emergency services or show your medical id if you have the feature.