What are some WhatsApp tricks we don't know?

Stop Someone From Knowing You Read His Message Or Not

You can stop whatsapp from showing someone else read notification. That is , no one can find out you read their message or not. The only disadvantage is that once you check this option, You also can not determine when your message was read by other.

Steps:-

Open your WhatsApp and tap three vertical dots icon on the top right of your screen.Now move to Settings > Account > Privacy.Uncheck Read receipts.

Red Hear Icon Expands And Animate

The red heart emoji on whatsapp expands and animate like a beating one. Try it.

Send A Message To All Your Friends At Once.
If you want to send a message to more than one person, you can use whatsapp broadcast feature.

For that you have to first create a broadcast list from your contacts.Once its ready, go to new broadcast and send message.It will be sent to all your friends.The only condition is that the person in your broadcast should also have your phone number saved on their phone.Backup Whatsapp Chats, Images And Videos On Your Google Drive Account 
. How to Hide Blue Ticks from Messages:

If you don't want to reply someone after reading their messages, you need to hide the blue ticks so that will sender think you didn't read his/her messages.
 To hide blue ticks follow the steps below:

Open WhatsApp.Go to settings.Tap on Account.Then tap on privacyFinally tap on Untick or uncheck Read Receipt.Done!

 How to mark Chats as Unread:

If you read a chat and forgot to reply it, you can mark the chat as unread so that you will see the chat later and reply it. Follow the steps-

Long press on the chat ( contact or group name) you what to mark unread.Open menu by tapping on the three dots at the right top corner of the screen.Tap on Mark as Unread.