> On iPhone at least you can require passcode by holding down the side button and either of the volume buttons for three seconds. Just ignore the power down/SoS

> On iPhone at least you can require passcode by holding down the side button and either of the volume buttons for three seconds. Just ignore the power down/SoS screen that comes up (or tap cancel) - by the time you see it Face/Touch ID is already temporarily disabled. You can also press and release the power button five times consecutively for the same power down/SOS screen, and then the biometric lock gets disabled (requiring the device passcode).