Enable Fingerprint Lock on WhatsApp for Android
Step 1: Start by updating your WhatsApp to the latest version if you haven't already. The functionality was added to the WhatsApp version 2.19.308 so make sure it is updated.
Step 2: Open WhatsApp on your Android smartphone and go to options and open the Settings page.
Step 3: Tap Account to open the account settings and tap Privacy.
Step 4: Under the Privacy tab, you will the option 'fingerprint lock' on the bottom. Tap to reveal the options.
Step 5: Toggle the Fingerprint lock option, you can choose between three modes; immediately, 1 minute, and 30 minutes.
That's all you need to do and every time you open WhatsApp, you'll be greeted with the lock screen and you'll have to touch the fingerprint sensor to access WhatsApp.
Step 6: In case, you haven't registered a fingerprint on your smartphone, you'll get a prompt that says 'Set up fingerprint'. You would need to register a fingerprint on your phone and you can do that in smartphone's Settings.
That's all folks, your conversations are now secure from snooping fingers, this feature won't even allow anyone to access WhatsApp even if they know your Phone's password unless they also have their fingerprint registered. You can still answer calls if the app is locked and if you haven't set up a fingerprint on your phone, you'll need to have it enabled in your phone’s settings. What do you think of this method, let me know in the comments below?