Even after locking WhatsApp with a locker app, it’s notifications still show message preview which, if you want to hide in iOS, you can go to Settings->Notifications and turn off “Show Preview”.
Sorry, by default this option is not available in Android but still if you want to implement, you need to block all notifications for your WhatsApp. To do this, go to Settings >> Apps >> WhatsApp >> Notifications and select “Block All” to block all the notifications for WhatsApp.
Disclaimer: These were all the WhatsApp Tips, Tricks, Tweaks, Hacks and Secrets that we have found till now. If you know any other interesting trick, please share it in the comments section below. All the WhatsApp Tips and Tricks we are providing through this article are for educational purpose only. Neither we nor WhatsApp (or any other app/service) will be responsible for any inappropriate use of these tricks.
If you're planning to become one of the smartest WhatsApp users, you can achieve that by learning all the tricks provided here in detail.
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