'Halo' and other big Microsoft games were almost individual iPhone apps

Apple's terms of service bans cloud gaming services from the App Store due to a requirement that "each game must be downloaded directly from the App Store."

This prevented Netflix-like cloud gaming services such as Google Stadia, Nvidia GeForce Now, and Microsoft xCloud from existing on Apple's App Store. If a developer wanted a game to exist on iPhone or iPad, the game would be required to have an individual App Store listing.

Apple even went as far as loosening gaming rules to allow developers to create catalog apps — that is, apps that would direct users to individual App Store listings.

Microsoft had concerns about turning each game into an individual app. The company had sent emails to Apple, as seen by The Verge, that explained that it wouldn't be practical — to Microsoft or App Store customers.

The concerns were many. Microsoft explained that Apple customers would receive Xbox titles significantly later to those on the streaming services. In addition, the company noted that Apple players would need to navigate to each title in the App Store and download it, rather than selecting from a list in a single app.

Microsoft also expressed concern over how it would make bug fixes and updates significantly more demanding on the app developers.

"We believe that the issues described here will create frustration and confusion for customers, resulting in a sub-par experience on Apple devices relative to the equivalent experience on all other platforms," Lori Wright, Microsoft's head of business development, wrote.

However, Microsoft wasn't entirely unwilling to bring Xbox-exclusive titles to the iPhone. Wright suggested that if Apple allowed the Xbox Game Pass library on the App Store, Microsoft would be willing to turn triple-A titles into standalone apps.

"This would be an incredibly exciting opportunity for iOS users to get access to these exclusive AAA titles in addition to the Game Pass games," she wrote.

However, because the apps would still require a single streaming tech app to work, it still violated App Store policies. Ultimately, Apple rejected the proposal. Microsoft would go on to launch Xbox Game Pass as a Safari-enabled service a month later.

Apple went on to clarify to The Verge that Microsoft had proposed a version of xCloud that was not compliant with the App Store, as well.

"Unfortunately, Microsoft proposed a version of xCloud that was not compliant with our App Store Review Guidelines, specifically the requirement to use in-app purchase to unlock additional features or functionality within an app," reads a statement via Apple spokesperson Adam Dema.

Microsoft's Xbox Cloud Gaming CVP Kareem Choudhry disagreed, telling The Verge, "The reasons for rejection were unrelated to in-app purchase capabilities; we currently provide Xbox Cloud Gaming through a singular Xbox Game Pass app in the Google Play Store without IAP enabled, for example, and we would do the same through the App Store if allowed."

Choudhry states that triple-A games aren't entirely off the table, either.

"In addition to Xbox Game Pass, we were also open to bringing select individual games to iOS as we do today with titles like Minecraft."