TV App Data Controls
It’s not mentioned in the release notes, but you’ll now be able to control your data usage when watching content in Apple’s TV app, with the ability to choose lower-quality streaming (“Data Saver”) and downloads (“Fast Downloads”) independently for your cellular and Wi-FI connections. So you could, for example, choose to use lower quality on cellular, while preserving high-quality streams on Wi-Fi, which is the default, or drop down to “Data Saver” mode on both if you have a metered (or slow) home internet connection. “Data Saver” mode will cap streams at 1GB/hour over Wi-Fi or 600MB/hour over cellular.
You can also choose to include only the necessary audio languages from movies and TV shows in order to limit the size of your download. “High Quality” videos include High Dynamic Range (HDR) content, which Apple notes will “take full advantage of your device’s screen,” but won’t be output over the Digital AV adapter.
Note that these settings don’t just apply to Apple TV+ content either, but also includes other services that you subscribe to through Apple TV Channels as well as any iTunes movies or TV shows that you’ve purchased or rented.