If you consider the app store market, we only have two options: Google Play Store and Apple App Store. However, Epic could soon change the scenario. Many developers and applications, including Netflix and Spotify, are also abandoning the commission cut off from Google and Apple. 

Epic launched its own Epic Games store in December to download PC games on Windows and MacOS platforms. A report in The Wall Street Journal indicates that Epic will start selling games for Android devices in 2019 and could soon launch a general application store to sell apps and games.
Apple and Google obtain 30% of the income generated by subscriptions and purchases of applications, while Epic Games Store charges only 12% of revenues. Epic surprised the world by getting rid of Google Play Store completely and made his popular Fortnite game available only in his store. 

Fortnite was a great success, and its popularity could push Epic to launch its own app store, ending the monopoly of Google and Apple.

The research conducted by Visible Alpha has stated that, of the total revenue generated by Alphabet (the parent company of Google) and Apple, 5% comes from the application stores. Epic's plans to launch its own app store could bring a paradigm shift in the way applications are currently downloaded.