Telegram is losing millions each year, paid by Pavel Durov, its founder.

"If you look at Telegram today, every month it burns over $1 million. It might seem that it’s just going nowhere, but if you want to come up with business model, you need to get to a decent size first. We have 62 million users at the moment, which is enough userbase to attract third-party developers to create products on top of your platform. You can’t do that from day one. It’s difficult."

http://kernelmag.dailydot.com/issue-sections/features-issue-...

I suspect the cost is even higher now.