Apple has sold more than 20 million Apple TV devices to date, according to Apple CEO Tim Cook. 

Cook announced the financial results during a recent conference call, according to AppDevice.com. 

The news comes as Apple is about to drop the "hobby" label from the set-top box. 

MacRumors obtained a transcript of the conference call. During the call's question-and-anwer session, Cook was asked about Apple TV, Fire TV and Amazon's new content deal with HBO. The Amazon-HBO deal means Prime Instant Video will be the only TV and movie subscription service to offer the premium channel's programming. 

One question asked was: "Apple TV is no longer a hobby, why did you make that distinction?"

Cook's responded by explaining the "hobby" label, as well as the sales of the set-top box. 

Cook responded: "The reason that I stripped off hobby label, when you look at sales of the Apple TV box itself, and the content that was bought directly off Apple TV, for 2013, that number was over $1 billion ... it didn't feel right to me to refer to something that's over $1 billion as a hobby.

"From an investment point of view, we continue to make the product better and better so it doesn't feel right from that POV either. We have HBO Go already on Apple TV and you have to authenticate in order to use it, but you have to do that with Amazon's service as well from my brief read of their announcement. From that, they got some older content from HBO to put on there and I haven't had a chance to evaluate exactly what it is and don't have a personal POV of that," he explained. 

"[We've] sold about 20 million Apple TVs and we have a pretty large installed base there," he continued. "I'm feeling quite good about that business and where it can go."

Apple TV will soon have a refreshed set-top box offering, which Apple is set to announce later this year. 

Apple has also been expanding Apple TV content, including adding three new channels a few days ago, along with Yahoo Screen and PBS channels. 

While Amazon is challenging Apple with its new Fire TV, Apple says they will continue to improve their popular product.