WhatsApp has updated its iOS app to add a new feature Screen
To enable the Screen Lock feature, go to your
What Screen Lock basically does it locks the entire WhatsApp behind your authentication system, so only those people Unlock the phone who are authorized to unlock the phone. there are like some limits in this feature like You can’t lock select chats within the app yet but even Screen Lock method is a useful feature for iPhone Users.
The New update is now available on the Apple App Store.