Apple has released a significant update to iTunes with a distinct lack of fanfare, despite a very important new feature. In version 12.6 of the iTunes desktop software for Mac and Windows, Apple users will now be able to rent a movie once, and watch it across devices – iPhone, iPad, Apple TV, and desktop.

The update follows Apple’s major product announcements for iPad and iPhone this week.

Significantly, the release notes for the update note that iOS devices running iOS 10.3, or Apple TV boxes running tvOS 10.2 will gain access to the multiscreen feature. Note, neither of those operating systems have made it out of beta yet and aren’t on general release, suggesting iPhone, iPad and TV users will gain access to these important updates very soon – potentially late this week, or early next.

Find out what’s coming in iOS 10.3

So, what was the situation before? A little bit messy. Previously, users were generally only able to watch content they downloaded on the device it was downloaded on. However, there were a few caveats – content downloaded on a desktop computer could be synced to an iPhone or iPad via iTunes and a USB cable – but that would remove the content from the desktop iTunes library.

But it was also possible to watch content from a Mac, iPhone or iPad by using Apple’s Airplay functionality.

Of course, iTunes content isn’t the only media you can stream via AirPlay – read our guide to Airplay and streaming media from a device.

Now, in iTunes 12.6, iOS 10.3 and tvOS 10.2, Apple’s motto is “rent once, watch anywhere.”

To update iTunes to the latest version, or check it’s been automatically updated, open up iTunes on a Windows PC or Mac, click on the file menu, and select Check for Updates.