The security features of our phone, like passcodes, fingerprint, face recognition, iris scanning, and so on are designed to act as the first layer of security. This in general prevents users from accessing our mobile devices without our permission. However when the phone does get unlocked, it’s more or less open season.
However according to a recent APK teardown of the beta of the Google app for Android, it seems that Google could be looking to add an extra layer of privacy protection to some of its services, namely Google Assistant where face matching could be introduced. Presumably what this does is that it will attempt to match the user’s face to the user’s profile, so that whenever that particular user uses Google Assistant, it would offer up a personalized experience, and also in turn prevent other users from finding out what you might have used the feature for previously.
This feature was actually spotted back in August of 2018, but its appearance again in the latest beta app suggests that we might be getting closer to seeing it launch. Also this feature doesn’t come as a complete surprise either, especially since there have been signs that shows Google is interested in facial recognition, and also how Google Assistant has voice profiles, so facial profiles seems like a natural extension.