WhatsApp has been one of the most used messages services around the globe, with about 1.5 billion active users. well, there are many schemes that spread in the WhatsApp but recently one another bug came to WhatsApp which will crash your WhatsApp.
If you touch the black dot it will crash your WhatsApp on your phone. the messages say "if you touch the black dot your WhatsApp will hang". But Only Android users seem to affect by this bug and IOS users are safe. However, the source of this bug is not identified yet.
Well, it's not for the first time that WhatsApp receives these kinds of messages to crash your phones. so advice is to be careful when clicking on these kinds of random messages.