Starting today, due to a recent US court ruling, App Store Review Guideline 3.1.1 has been updated to introduce the right to link. StoreKit purchase (US), which allows apps offering in-app purchases in the iOS or iPadOS App Store on the US storefront has the option to include a link to the developer's website that notifies users of other ways to purchase digital goods or services.
We believe Apple's in-app purchasing system is the most convenient, safe and secure way for users to purchase digital goods and services. If you plan to use this right with in-app purchasing, which continues to be required for purchasing digital goods and services in your app, it is important to understand that certain App Store features, such as Ask to buy or Family Sharing, will not be available to your customers when they make purchases on your website. Apple will also not be able to help customers with refunds, purchase history, subscription management and other issues encountered when purchasing digital goods and services. You will be responsible for resolving these issues with customers.
A commission will apply to digital purchases facilitated through the StoreKit (US) right-to-purchase link. For full details on commissions, request entitlement, usage guidelines and implementation details, see our support page.