India, May 22 -- Microsoft has pointed to Apple's App Store policies as the cause behind the ongoing delay of its Xbox mobile app store. The company shared its concerns in a legal filing this week, backing Epic Games in its dispute with Apple over payment rules.

Microsoft filed an amicus brief supporting Epic Games' case, which challenges Apple's requirement that all digital purchases within iOS apps use Apple's own payment system and pay a 30 percent fee. Microsoft warned that if Apple wins its appeal, it could undo recent changes allowing payments outside of apps, affecting other developers as well.

Apple is fighting against rules that let developers promote alternative payment options within their apps. For instance, when Fortnite re...