WhatsApp seems to be working on a bunch of new features for iOS that are going to be implemented in the upcoming update. The previous update brought in some UI improvements, support for consecutive voice messages autoplay, more status replies options and some new information about the Dark Mode. Now it looks like WhatsApp's next update will be focused more on security for the iOS devices.
As per a report by WABetainfo, it looks like WhatsApp is working on integrating TouchID and FaceID in its app. The privacy settings in WhatsApp will soon be having a new option called as "Require TouchID". Devices such as iPhone X, iPhone XS, iPhone XS Max and iPhone XR will have FaceID support instead.
With this setting enabled, everytime you open WhatsApp you will need to authenticate it with TouchID or FaceID, thus providing an extra layer of security on the platform.
If either of these authentication methods fail, then the phone will ask for the passcode. Neither your fingerprint data nor your facial data is sent to the WhatsApp servers.
The feature is still in its 'alpha' stage as per the report which means that iOS users will likely be able to see this feature in the next update.
WhatsApp Business will also be having this authentication feature as well.