According to the WABetaInfo website, while choosing The Free Android, WhatsApp has focused on implementing this new feature for weeks on Android or iOS phones that are not yet available – this technology is only available in beta. Because they are trying a little improvement before being activated for everyone.
A new way to add contacts reminds you of ID cards that already exist in other applications, such as Instagram or Snapchat, and it works like this:
In Account Settings, you must click the option to share data with the QR code that you want to scan to your device's camera. When the code is found, WhatsApp adds the new contact to your address book.
This feature is also very useful for companies that want to use WhatsApp when publishing QR codes to websites or facilities.
source : 20 minutes