I don't really use WhatsApp much, but their post last year about why they don't sell ads came up in my stream this weekend, and it seemed worth noting:
When we sat down to start our own thing together three years ago we wanted to make something that wasn’t just another ad clearinghouse. We wanted to spend our time building a service people wanted to use because it worked and saved them money and made their lives better in a small way. We knew that we could charge people directly if we could do all those things. We knew we could do what most people aim to do every day: avoid ads.
No one wakes up excited to see more advertising, no one goes to sleep thinking about the ads they’ll see tomorrow. We know people go to sleep excited about who they chatted with that day (and disappointed about who they didn’t).
It's echoed somewhat by the initial post by App.net founder Dalton Caldwell:
Years later a site called Github came out. It was good. They had no advertising, but charged money for certain features. They quickly became profitable because the service was so good and so important, people were willing to pay. Github has become a much-loved brand and service, and many would agree that it is a key piece of infrastructure in the technical renaissance we are currently experiencing. Github is apparently profitable, and it sounds like the people that work there spend their time trying to make the best service possible, as opposed to spending their time trying to extract additional pennies out of their users.
Also, given the revelations about GCHQ and the NSA indiscriminately listening in on what we previously thought of as private spaces, the idea that personal data isn't the currency you pay with to access a useful service is an attractive one.
And as a result, I'm giving it another go today, to see how well I get on with the service. Matt Gemmell's post earlier in April this year is a good background if the service is new to you.
Unsurprisingly, I'm mrchrisadams on app.net, - say hi.