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This free-to-play business model set Fortnite apart from its peers and has proven to be one of the reasons for its success. In its first 10 months, it amassed an audience of 125 million players and netted $1.2 billion in revenue. When the Fortnite App launched on iPhone on April 1, 2018, it reportedly made $2 million a day from players on Apple Inc.’s (AAPL) iOS. While other games have netted $1 billion in the first year after their launch, Fortnite was the first game to generate such a massive amount of revenue as a game that is offered for free by its developer.
https://www.investopedia.com/tech/how-does-fortnite-make-money/