The European Commission has found Apple in breach of its Digital Markets Act following an investigation launched in March against the firm.
In its preliminary findings, the EU Commission said it found Apple's rules of engagement did not comply with the DMA because it "prevent[s] app developers from freely steering consumers to alternative channels for offers and content."
The EU Commission found that Apple's business terms do not allow developers to freely communicate with consumers to promote alternative app stores, and that while the firm does allow steering by allowing developers to include links to web pages in their apps, they are met with several restrictions.
This includes Apple's "core technology fee" which sees developers pay €0.50 for every app install per year after the first install distributed via the App Store and alternative marketplaces.
The regulator has also launched a non-compliance investigation in response to Apple's business terms, including the core technology fee, eligibility requirements for developers, and the process to download alternative app stores on iPhones.
As a result, Apple could face daily fines of up to 5% of the company's average turnover, amounting to over $1 billion.
"Under the DMA, developers distributing their apps via Apple's App Store should be able, free of charge, to inform their customers of alternative cheaper purchasing possibilities, steer them to those offers and allow them to make purchases," the regulator said.
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