Telegram has 900mn users and is nearing profitability, according to the owner of the secretive messaging app, as the company moves closer to a potential blockbuster stock market listing.  Pavel Durov told the Financial Times that Dubai-based Telegram had grown to become one of the world’s most popular social media apps while making “hundreds of millions of dollars” in revenues after introducing advertising and premium subscription services two years ago. “We are hoping to become profitable next year, if not…