Substack writers can now direct U.S. readers to (often cheaper) web-based subscriptions on iOS

Newsletter subscription platform Substack will begin taking advantage of an option on the U.S. App Store that allows users to make purchases outside of Apple’s in-app purchasing system. This functionality is permitted by a change to the App Store’s rules in May, as a result of Epic Games’ antitrust lawsuit against the tech giant.

Since then, a number of top apps have moved to offer in-app purchase links that point to their own websites, including Spotify, Patreon, and the Amazon Kindle app, among others.

In Substack’s case, support…