YouTube for iOS has just been given full Google Cardboard support, allowing iPhone users to watch any video in VR.
While the app has had the ability to view 360-degree video since last year, this is the first time that iOS users have been able to combine it with Google Cardboard to experience mobile VR.
As well as purpose-made 360-degree content, users can also use the feature to watch regular videos in a VR environment, viewing them on a big screen in a sort of 'virtual cinema'.
This is the first time that major VR support has come to iOS. While third-party VR apps are available, YouTube sports the largest single library of 360-degree content.
As one would imagine, Google has been prioritising its own OS, and the Android version of YouTube has been enjoying full Google Cardboard support since November last year.
Although Samsung has been offering premium virtual reality via the Gear VR for over a year, Google Cardboard remains the most accessible form of entry-level VR for most consumers.
The news fuels rumours that VR will be high on the agenda at Google's upcoming I/O developer's conference, set to kick off tomorrow in Google's hometown of Mountain View, California.
The company is expected to launch an updated version of Google Cardboard at the conference, potentially alongside a standalone 'Android VR' headset.
Whatever Google unveils at its keynote tomorrow, this news is evidence that Cardboard is shaping up to be a key lynchpin of the company's nascent VR strategy.
