Apple TV got a boost Saturday with the addition of iTunes Extras in its bid to catch up with Roku, which is the top-selling set-top box, figures from Multichannel News indicate. Apple has a 26 percent share of the market, far behind Roku's 44 percent.

ITunes Extras, which will operate from a cloud-based platform, includes commentary from directors and actors, deleted and bonus scenes, music videos gleaned from soundtracks, and behind-the-scenes clips. The cloud platform will enable moviemakers to add material after DVD/Blu-ray release, Digital Trends reported.

Previously, iTunes Extras was available only on PC and Mac versions of iTunes. CNet said iOS 8 will change all that, making iTunes Extras available across Apple devices.

Apple released iTunes 11.3 Friday and said the new content will be added for free to previously purchased movies, MacRumors reported. The update can be downloaded from either Apple.com or the App store.