Facebook is buying WhatsApp for ~$19 billion. There’s no denying that’s a big number. But, a big number doesn’t necessarily mean it’s an expensive number. In fact, it might be a relative bargain, even at $US19 billion.
This chart from Statista shows that the per-user price Facebook paid for WhatsApp. Compared to all the other major social networks, WhatsApp is fairly cheap. Part of the reason is that WhatsApp hasn’t effectively monetized these users. In the long run, though, it’s not hard to see WhatsApp getting anywhere from $US1-$12 per user annually, which would make it a lucrative business.