https://www.techdirt.com/articles/20210428/14553046696/content-moderation-case-study-apple-blocks-wordpress-updates-dispute-over-non-existent-in-app-purchase-2020.shtml

Summary: Apple controls what apps get onto iPhone and iPads via its full control over the iOS App Store. Every app (and its updates) need to be reviewed by Apple staff before it’s allowed in the store -- and Apple puts in place its own rules for what is and what is not allowed.

One of those rules is that Apple takes a 30% cut of any sales. That fee has become somewhat controversial, especially among service providers who don’t rely on the App Store for discovery, but whose customers likely come on their own -- including Spotify and Epic Games. Spotify, in particular, has urged users to subscribe directly, to avoid having to pay the additional amount per month to cover Apple’s fees. In response, Apple forbade Spotify from even mentioning that it’s cheaper to subscribe outside of the App Store, which is now a central piece of an antitrust fight that is ongoing in the EU.