Anonymous: 2 months, 2 weeks ago
Its really quite clever this one. The first message is harmless, but if you do as it asks, you add the sender of the message to your contacts as "WhatsApp". If a sender is in your contacts list, URLs are clickable.
When you click the link, you tell them which of the 1000s of numbers they have spammed have done this.
The malicious payload will be in the next message. This time It will appear to be officially from WhatsApp and be clickable.