Whatsapp New Authentication Feature Spotted; Details here
WhatsApp will show a sign indicating users that they can now unlock the app using the fingerprint authentication. As mentioned, this feature is not enabled yet, so you won't see it even if you are on the latest beta version 2.19.83. Probably, this feature should roll out for beta users in its next updates.
WhatsApp users can lock their account and unlock it using a fingerprint sensor, Photo: PTI