Compared to the likes of the Roku, which boasts a 1,000+ channel library, the Apple TV doesn’t exactly have a lot of different media channels. The Apple TV boasts only has around 33 third-party channels. Much of the reason the channel selection is so limited is because, unlike Roku, the Apple TV is a closed ecosystem: only Apple can release a new channel for its streaming set-top box.
Things, however, are getting rapidly better, as the above chart shows.