Epic Games just recently added a major discount in Fortnite's in-game currency, so long as players bought these directly from the game developer instead of Apple. This payment scheme bypassed Apple's IAP system, making things cheaper for the users. However, this was not approved by the latter company as Apple hits back by removing Fortnite from the App Store.
The company behind the wildly popular battle royale game seemed to have designed this to provoke Apple to make a response. In a statement made to The Verge, Apple made the decision to remove the game from the App Store, pointing out that the feature enabled was not reviewed by Apple and has violated the guidelines "that apply to every developer who sells digital goods or services."
Apple says they will be making an effort to "work with Epic to resolve these violations" so that the game can return to the App Store once again. You can check out their full statement below.
"Today, Epic Games took the unfortunate step of violating the App Store guidelines that are applied equally to every developer and designed to keep the store safe for our users. As a result, their Fortnite app has been removed from the store. Epic enabled a feature in its app which was not reviewed or approved by Apple, and they did so with the express intent of violating the App Store guidelines regarding in-app payments that apply to every developer who sells digital goods or services.
Epic has had apps on the App Store for a decade, and have benefited from the App Store ecosystem - including its tools, testing, and distribution that Apple provides to all developers. Epic agreed to the App Store terms and guidelines freely and we're glad they've built such a successful business on the App Store. The fact that their business interests now lead them to push for a special arrangement does not change the fact that these guidelines create a level playing field for all developers and make the store safe for all users. We will make every effort to work with Epic to resolve these violations so they can return Fortnite to the App Store."
Epic's decision for players to get access to V-bucks for cheaper is essentially something for the better. It looks like Epic isn't planning to budge as well so they might be in quite a pickle for a while and the gamers won't be exactly happy about this. Apple is willing to work things out but Fortnite's future on the App Store is uncertain.