https://techcrunch.com/2021/10/22/apple-updates-its-app-store-guidelines-to-permit-developers-to-contact-customers-about-other-payment-methods/

Apple today introduced a new set of App Store Guidelines which include three key changes. One of the changes is the result of a previously announced settlement agreement with a class of U.S. app developers. It clarifies that developers are allowed to communicate with their customers about other payment methods available outside their app. Related to this, another new guideline explains that apps may request customer information like name and email, but the request must be optional for the user and shouldn’t prevent them from using the app.

The third guideline is unrelated to legal action, and simply details how developers can use a new App Store feature, called in-app events, which rolls out next week.