I was very happy to pay USD 1 a year for WhatsApp. I think they were already profitable by te time they sold out. There's also other monetization options: AP

I was very happy to pay USD 1 a year for WhatsApp. I think they were already profitable by te time they sold out. There's also other monetization options: API access for businesses. Premium accounts. Etc. And FTR: I'd gladly paid 10 times as much as WhatsApp charged if that was the price- as long as they didn't sell out to my enemies.