Apple’s TV business still consists only of an over-the-top streaming media box, and not a proper TV set despite longstanding rumors that kind of hardware was on the way – but it’s showing impressive growth nonetheless. The company sold approximately 10 million Apple TV units last year, according to estimates based on figures Apple CEO Tim Cook offered up at the annual Apple shareholder meeting today. Apple made over $1 billion in revenue from sales of its Apple TV devices in 2013, Cook explained during the meeting with investors, which translates to sales at or around 10 million units, as noted by Asymco’s Horace Dediu. With just over 5 million units sold in 2012, that makes Apple TV the company’s fastest growing hardware product category, according to the analyst, with around 80 percent year-over-year growth.