
Facebook Messenger has updated the app for its iOS users with support for biometric authentication. With version 274.1, iPhone and iPad users can now lock the device using Face ID or Touch ID, depending on the device’s capabilities. It’s a nice feature to prevent your private conversations from a friend or a family member.
Here’s how to unlock WhatsApp on iOS with Face ID or Touch ID in simple steps.
How to Lock WhatsApp on iOS with Touch ID or Face ID
Setting up this feature is really simple. The feature can be used by updating the Facebook Messenger app to the latest version, version 274.1, from the App store. In Facebook Messenger, tap your profile picture in the top left. Scroll down and click Privacy and the tap App Lock.
Tap Require Face ID or Require Touch ID to turn on and off. When you enable this toggle, you will get the option of whether you want to lock Facebook Messenger immediately after you exit it or after 1 minute, 15 minutes, or an hour. Select your preferred time and you are done! Keep in mind that even with App Lock turn on, you can still see message notifications and calls without unlocking the app.

App Lock coming to Facebook Messenger for Android
A Facebook spokesperson has told The Verge that the App Lock feature will come to Android in “the next few months”, thus allowing Android smartphone users to lock their chats behind a biometric authentication method.
WhatsApp for iOS already supports Face ID/Touch ID lock feature
Last year, Facebook-owned chat service WhatsApp for iOS was updated with biometric authentication. The update allowed iPhone users to lock WhatsApp on their smartphone by activating Face ID or Touch ID.
How to use Touch ID and Face ID on WhatsApp:
# Download the latest WhatsApp iOS update.
# Go to Settings, Account, Privacy, then Screen Lock on your iPhone.
# Users must choose which biometric authentication option they want – Face ID or Touch ID.
#Select time duration for Face ID or Touch ID to be required.