Ever passed your phone to a friend and instantly panicked about the messages they might see come through? Yeah, we haven't either. For those that have, you can turn off message preview on iOS so only the contact's name will appear, rather than their life story.
In Android, it's not possible through the WhatsApp app but you can stop private information showing up on your lock screen in Android itself.
iOS: Settings > Notifications > Toggle off Show Preview
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