While it’s turned on, it automatically keeps users from installing apps unless they come from “authorized sources” — namely, Google and Samsung’s app stores. Epic claims there’s no process for any rival store to become “authorized.

Some users may know that Epic Games, the developer of Fortnite, has had its own app store for a while now, the Epic Games Store. The company also won an antitrust lawsuit against Google last December that found Google held an illegal monopoly on app distribution and in-app billing services for Android devices.

Epic Games has accused Samsung of making it too difficult to download its massively popular video game Fortnite on certain mobile devices.