https://wccftech.com/apple-faces-antitrust-charges-in-eu-in-dispute-with-spotify/

In 2019, Spotify filed a complaint with the European Commission; the complained suggested that Apple enforces App Store rules that "purposely limit choice and stifle innovation at the expense of the user experience," Spotify also accused the company of being a player as well as a referee, which basically suggested that the company is deliberately causing disadvantage to other app developers.

Spotify even went into particulars and talked about how Apple's 30 percent commission on App Store purchases, including in-app subscription, forces the streaming service to charge existing subscribers $12.99 a month for their premium plan on the App Store. So that Spotify could collect the $9.99 a month it usually charges.