A year ago Xbox president Sarah Bond revealed that Microsoft was planning to launch a new Xbox mobile web store in July 2024. That never happened. I’ve been wondering what the hold up has been over the past year, and it seems we might have an answer: Apple.

Microsoft filed an amicus brief late on Tuesday, in support of Epic Games’ ongoing fight with Apple’s control over the App Store. The brief takes issue with Apple’s attempt to overturn the injunction that allows Epic and other developers to freely advertise alternative payment methods in their apps, and not have to pay Apple additional fees for purchases made outside of apps.

It’s a key ruling that has already allowed Fortnite to return to the App Store in the US, complete with the ability for Epic Games to link out to its own payment system inside the game. Microsoft has wanted to offer a similar experience for its Xbox mobile store, but it says its solution “has been stymied by Apple.” Here’s how Microsoft explains it:

The district court’s injunction allows Apple to maintain its in-app exclusivity but at least should have enabled Microsoft to offer consumers a workable solution by launching its own online store — accessible via link-out — for in-app items to be purchased off-app and used in games or other apps. And that is what Microsoft wants to do. But even this solution has been stymied by Apple. Prior to the district court’s most recent order, Microsoft had been unable to implement linked-out payments (or even inform customers that alternative purchase methods exist) because of Apple’s new anti-steering policies that restrict Microsoft’s communication to users and impose an even higher economic cost to Microsoft than before the injunction.

The court ruling makes it possible for Microsoft to now launch its Xbox mobile store, but it’s clear that the software giant also wants to ensure Apple’s appeal against the ruling isn’t successful. If Microsoft did launch its Xbox mobile store and then Apple won a temporary stay, it may have to pull that store pending the appeal process.

Microsoft even notes in its filing that “Apple makes no argument that the technical or policy changes cannot be undone,” so it’s urging the ruling to be enforced pending Apple’s appeal. “Microsoft’s own experience managing app stores confirms that Apple’s policies could be restored if Apple ultimately prevails on appeal.”

The court ruling also impacts Microsoft’s main Xbox mobile app. “Similarly, Microsoft has long sought to enable Xbox app users on iOS to both buy and stream games in the app from the cloud or their other devices,” says Microsoft in its filing. “Apple’s policies have restricted Microsoft’s ability to offer these functionalities together; the injunction allows Microsoft to explore this possibility.”

Microsoft started rolling out the ability to purchase games and DLC inside the Xbox mobile app last month, but it had to remove the remote play option to adhere to Apple’s App Store policies. You can’t currently buy an Xbox game in the Xbox mobile app on iOS and then stream it inside that same app. You have to manually navigate to the Xbox Cloud Gaming mobile website on a browser to get access to cloud gaming.

Sarah Bond also announced plans to let players purchase and play games within the Xbox app on Android in October, just days after a court ruled that Google must crack open Android to third-party app stores. The feature was supposed to arrive in November, but Bond then blamed a “temporary administrative stay” for holding it back.