Face unlock is available on countless smartphones these days, but many of us seem to forget that Android has always had the feature, albeit easily fooled.
Android Smart Lock "Trusted Face" was added in 2014 and is accessible to users on all Android devices until recently. However, it no longer exists on devices running Android 10 or lower.
The resource was accessible at Settings -> Security -> Smart Lock -> Trusted Face.
- Android Q beta in native support for Face Unlock
Unfortunately the "trusted face" has always been far from the most secure method of securing devices as it has never used biometric data, only on aspects of the image captured by the camera to unlock the device.
A photo has been used several times to trick devices. However, the removal is not a backward step but a forward step, as the inefficient solution was removed in Android 10 and will not return in future versions, but a new, more secure face authentication method is being studied.
But it's not just Android 10 that no longer has the "trustworthy face" option, the option has been removed from the OnePlus 6T, Samsung Galaxy S9 and S10, Nokia 3.2, all running stable Android 9.0 Pie.
This is because Smart Lock was never really part of the firmware but was always controlled by Google Play Services - Trusted Places, Trusted Voice and On-Body Detection such as smartwatches, smartbands and even bluetooth devices that were added in a Play Services update .
So it's likely that a recent Play Services update removed the option. It's just not known for sure if it's just a temporary case and would come back once the bugs are fixed or if it's been fixed for good.
