Apple v. Epic Games is officially over. The U.S. Supreme Court has declared that it will not hear the two companies' appeal, leaving the lower court's existing ruling in place (via Reuters).

The two companies have been engaged in a legal battle since 2020 over whether Apple is allowed to block developers from processing app payments outside of the App Store; when Epic attempted to do so with Fortnite payments, Apple blocked App Store, resulting in Epic retaliating with a lawsuit.

Epic's lawyers were unable to confront Apple with antitrust charges when they argued their case in the lower court. However, the district court found that Apple had engaged in anti-steering behavior, i.e., illegally preventing developers from informing users of alternative payment methods. An injunction was issued in 2021 to force Apple to remedy this, but that remedy was stayed while Apple's appeal was being processed.

Now that the legal proceedings are (for now) over, Apple must comply with that injunction.

In a new section of the App Store Review Guidelines entitled "Link to Other Purchase Methods" and a new page in StoreKit regarding distribution of apps with external purchase links, Apple details how apps can and cannot use external payments. These changes are limited to the iPhone and iPad App Stores, and only in the U.S.

. Apps must apply for special permission to use their own payment links, which must be managed by the app itself, but only if the app also offers payments within the App Store. Developers are also allowed to communicate these payment options outside the app, including if they are cheaper than in-app purchases.

Apple is quite specific about how the link must work and what language developers can use to advertise external purchases. The app is also forced to display an "in-app system disclosure sheet," a large warning screen that spells out in clear language that the user is leaving Apple's ecosystem for this payment.

Once an external payment is made, Apple typically takes a 27% cut, or 12% for developers participating in the App Store Small Business Program. Developers must keep their own records of outside purchases to meet Apple's guidelines and submit them to Apple upon request.

Even if you live in the U.S., where these new rules apply, you won't immediately notice these changes unless you are a developer yourself. However, given that Apple has not made it easy or attractive for users to pay outside of its ecosystem, there is no telling how many apps will actually take advantage of the new payment options and how quickly they will be adopted.

Similarly, the guidelines may not last long in their current form; Tim Sweeney, founder and CEO of Epic Games, has already declared that he will challenge them for Epic's bad faith compliance with the injunction; Apple and Epic's legal battle may not be over yet.