Microsoft’s founder, Bill Gates, says that Facebook and Google weren’t the only companies interested in acquiring WhatsApp: Microsoft was also “willing” to buy the messaging app.

Facebook bought the five-year-old WhatsApp cross-platform text message replacement app, which sends messages via phones’ data connections rather than SMS, for $19bn in February. WhatsApp is Facebook’s biggest acquisition and showed the importance of the drive to mobile from the desktop for the social network.

WhatsApp rebuffed a $1bn offer from Google in April last year prior to the social network’s bid. Facebook’s founder Mark Zuckerberg said that WhatsApp was on track to connect 1 billion people which is what made it valuable.

“Microsoft would have been willing to buy it, too. I don’t know for $19bn, but the company’s extremely valuable,” Gates, 58, told Rolling Stone in a wide-ranging interview covering technology, climate change and God.

‘User bases are extremely valuable’

“I think [Zuckerberg’s] aggressiveness is wise – although the price is higher than I would have expected. It shows that user bases are extremely valuable,” said Gates.

Gates, who co-founded Microsoft in 1975, explained that the community and user base is the most valuable aspect and that it might start with messaging, but the company can then expand the service to sharing photos, documents and games.

WhatsApp founder and chief executive, Jan Koum, announced at Mobile World Congress in Barcelona that the company would be adding voice messaging in the second quarter of the year.

Gates praised Zuckerberg’s drive, but described him as “more of a product manager”, insisting that he was more of a coder starting with architecture where Zuckerberg “starts with products, and Steve Jobs started with aesthetics.”

• Mark Zuckerberg said that he would have paid more than $19bn for WhatsApp