The feature adds an extra layer of security for you in case you leave your phone behind and your nosy friend wants to peruse your chats. So since fingerprints are unique, they wont be able to access your WhatsApp.
How it works
You can enable this feature from the Settings menu, then head to Account section and move to Privacy. Furthermore, after you opt for the biometric authentication feature in the settings, and WhatsApp will then ask you to punch in fingerprint in an order to confirm the operation.
As WABetaInfo reports, “after enabling it, you can configure when the Authentication feature should lock the app: Immediately, After 1 minute, After 10 minutes or after 30 minutes”. And “When WhatsApp isn’t able to recognize your fingerprint (or there are too many attempts), WhatsApp shows an error.
When will it be available?