Apple has announced that it is adding support for Dolby Atmos to its Apple TV 4K box as part of the forthcoming tvOS 12 update. What's more, your existing movies and TV shows that support Dolby Atmos will be upgraded for free.

It's a similar story to when Apple added 4K HDR support for video. It also upgraded supported content then too.

By adding Dolby Atmos, the Apple TV 4K box has become one of the best streamers on the market - in terms of picture and audio performance.

• Dolby Atmos explained: What is it and how do I get it?

Movies with Dolby Vision and Dolby Atmos will be available through iTunes and Apple claims that it now has the most amount of content in 4K of all digital stores.

Apple isn't the first to offer both Dolby Atmos and Dolby Vision, Rakuten announced a similar move for LG TVs recently, but by offering free upgrades for existing, bought movies, it's showing that it is committed to offering the best quality available.

It certainly makes the current Apple TV an interesting proposition as an addition to any home cinema set-up.

Apple hasn't yet said when the new tvOS or Dolby Atmos content will be available, apart from "this fall", but we'll update when we know more.