The second feature automatically labels the unseen messages under a "Unread Message" label in chats. This label will be there until you see all these messages. All unseen messages will come under this label. This is another quite useful feature from WhatsApp. See the image below.
How To Use The Quick Reply In WhatsApp
- Open the chat with your friend.
- Now long tap any message.
- Tap the reply button on top left corner.
- After tapping the reply button the message will be quoted automatically.
- Type your message as a reply to that specific message and tap the send button.