Apple on Monday criticized a pornography app newly available on iPhones in the European Union, saying the bloc's digital policy was undermining consumer confidence in Apple.

Since it first opened the App Store on iPhones in 2008, Apple has controlled what apps could be downloaded to the devices, with then-CEO Steve Jobs saying in 2010 that keeping porn off the iPhone was Apple's "moral responsibility" and one of the company's major motivations for acting as a gatekeeper.

In the EU, Apple's gatekeeper status changed with the 2022 adoption of the Digital Markets Act (DMA), which required Apple to allow alternative app stores. One of those stores, called AltStore, has begun distributing an app called Hot Tub, which describes itself as "a private, secure, and elegant way to browse adult content."

In a statement, Apple said it is "deeply concerned about the safety risks that hardcore porn apps of this type create for EU users, especially kids. This app and others like it will undermine consumer trust and confidence in our ecosystem."

AltStore said it had received backing from Epic Games, the creator of the "Fortnite" video game that pursued an antitrust complaint against Apple. AltStore said it used that funding to pay fees that Apple charges to alternative app stores that are under investigation by the EU, according to media reports.

As part of its alternative app store process, Apple still requires apps to undergo a baseline review called "notarization" that checks for cybersecurity threats such as known malware but does not involve approving the app's content.

AltStore said Hot Tub was notarized by Apple and in a post on X described that move as making the app "the world’s 1st Apple-approved porn app," raising Apple's ire.

"Contrary to the false statements made by the marketplace developer, we certainly do not approve of this app and would never offer it in our App Store," Apple said in a statement. "The truth is that we are required by the European Commission to allow it to be distributed.”

AltStore said comments on X were in reference to Apple's notarization decision, and Hot Tub steered press inquiries to AltStore.

In a post on X, Epic Games Chief Executive Tim Sweeney said his firm has supported laws such as the DMA because "when Apple are allowed to be the gatekeeper of competing apps and stores, they grossly misuse that power to disadvantage competition."

He added that Epic's own app store in the EU, which rolled out last year, is not carrying the Hot Tub app and has never hosted porn apps.