https://www.developer-tech.com/news/2018/aug/03/apple-affiliate-commissions-apps-store/

Effective as of October 1st, Apple will no longer provide affiliate commissions for referrals to apps on its App Store.

The move is of particular concern to publishers who focus on game and app reviews for iOS and Mac. While the commission Apple provides is only around 2.5 percent, a small percentage of the company’s revenue, they are of large importance to such websites.