In February this year, WhatsApp had rolled out the authentication feature for iOS beta users. After more than six months, the feature has finally been made available for Android beta users. As spotted by the folks over at WABetaInfo, the Fingerprint lock feature will allow WhatsApp beta users on Android to open the app using the fingerprint sensor on their phone. Similar to the Authentication feature on iOS, users can still reply to messages from the notifications shade and answer calls, even when the app is locked.
Having biometric unlocking on your device is a necessary security inclusion that valuable data on your phone stays secure. The latest WhatsAp beta for Android increases your device security by adding the much-anticipated fingerprint locking – which is available starting.
The new app authentication method is available if you update WhatsApp to the 2.19.221 Android beta version. It shows in the app settings as Fingerprint lock and should be rolling out now if you are already enrolled in the beta program.
Once you have configured the fingerprint lock in your updated version of WhatsApp, it is worth noting that you will still have the ability to read messages on the lockscreen and notification shade. Also, you will be able to use the Android quick reply in order to respond messages and chats. On the whole, the fingerprint lock only applies when you want open the app.
How to Enable WhatsApp Fingerprint Feature?

The feature is available in the latest 2.19.221 beta version of the app. If you have already updated WhatsApp to the latest version and still do not see the Fingerprint lock feature, you should try reinstalling the app after backing up your chat history. In case the feature still doesn’t show up, all you can do is wait for it to be activated, provided your device meets the requirements.
In order to enable the feature, you need to head over to Settings >> Account >> Privacy and tap on the Fingerprint lock option. Once you enable it, you will need to touch the fingerprint sensor every time you wish to unlock WhatsApp.
You can also choose how long the app should stay unlocked once you open it. You can have the feature automatically lock the app after 1 minute or 30 minutes. If you disable the “Show content in notifications” option, WhatsApp will no longer show the sender and message preview when you have Fingerprint lock feature enabled.
Some may not see the feature after updating. It may require a clearing of the app cache and maybe it needs reinstalling the WhatsApp. Just keep in mind that you’d better to back up your chats to ensure that you don’t lose any important data or messages. If it continues to not become available, and your device meets the minimum requirements, then it may take a while to activate.