Epic Games Inc. expanded its antitrust legal fight with Alphabet Inc.’s Google by accusing the tech giant of conspiring with Samsung Electronics Co. to block rival app marketplaces through default settings on mobile devices sold all over the world.

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.

Video game company Epic Games filed a federal lawsuit Monday accusing Google and Samsung of colluding to harm third-party app stores on smartphones running Google’s