Apple’s Safari browser will soon stop websites from using your phone’s motion data by default, potentially breaking web-based AR and VR experiences that rely on this functionality, reports DigiDay. With iOS 12.2, the company is introducing a new privacy setting called “Motion and Orientation Access” into version 12.1 of its browser, which will be disabled by default.

Apple did not immediately respond to a request for comment, but DigiDay speculates that a report from Wired last year is to blame for the changes. The report raised concerns that thousands of sites used scripts that pull data from a phone’s motion-sensors without the user’s consent. Many of these sites then used this data for tracking, analytics-gathering, and audience recognition.

Multiple VR and AR developers spoken to by DigiDay said that they expected the changes to break aspects of their sites’ functionality. It could affect web-based experiences such as promotional sites for Sony’s First Man, Spider-Man: Into the Spider-Verse, and the “Samsung Within” site, for example.

The report noted that access to other data from a phone — such as location data — is preceded by a pop-up asking for user permission, but it’s currently unclear whether sites will be able to generate a similar notification to ask for access to motion data. DigiDay speculates that an affected website could detect when Safari is being used to access it, and could direct a user to the relevant settings page to give their consent.

Even if this is possible, it could still be a problem for developers. The attraction of web-based AR and VR content is its low barrier to entry compared with alternatives that require a dedicated app or headset. However, requiring people to open their settings menu introduces a barrier — albeit a small one — that could be the difference between someone trying a VR experience for the first time, or giving it a pass.