Access to WhatsApp’s iOS app can now be protected using your phone’s biometric security. Depending on your iPhone model, you’ll get the option of using either Face ID or Touch ID to restrict access to the software. The feature, which was first spotted by 9to5Mac, was made available with version 2.19.20 of WhatsApp, and can be enabled from the app’s Privacy menu within Account Settings.
Although you can’t secure your messages on a per-chat basis, the new layer of biometric security should give the contents of your messages more protection even if your phone itself is already unlocked. You’ll want to be careful about your notification settings if you choose to secure your app, though, specifically message previews. If you have them turned on then you’ll be able to both see and reply to any messages without having to unlock the app. You’ll also be able to respond to any WhatsApp calls without needing to unlock the app first.
At the moment, the feature is only officially available within the iOS version of the app, but recent testing noticed by WABetaInfo last month suggests that an Android release is on the way as well.