Epic rogue released a version of Fortnite on iOS that allowed you to bypass Apple’s In-App-Purchase system. If you want IAP you have to use Apple’s system.

Apple quickly removed Fortnite because it violated App Store policy. Epic then sued Apple for anti-competition practices.

The crux of the suit is should Apple be allowed to block developers from creating competitive solutions such as alternative app stores or alternative IAP systems To Apple’s? Right now you can’t. You have to download through the App Store. Other than PWA and that would take some explaining. If you don’t know what a PWA that is part of Epic’s argument.

If Epic wins that would effectively mean that Apple wouldn’t be allowed to block say for an example an Epic Games store on iOS.

This has the huge possibility of being a landmark case in anti-trust.