Apple previously only opened its own App Store for software installation in iOS, but in iOS 17, it will open third-party app stores. According to Bloomberg's Mark Gurman, iOS 17 will introduce side-loading for the first time, allowing iPhone users to download applications from unofficial app stores. This change will allow developers to make their apps available for download without having to list them on the Apple App Store.
The EU's Digital Markets Act (DMA), which will take effect on November 1, 2022, requires "gatekeeper" companies to open their services and platforms to other companies and developers. This will also have a significant impact on Apple's platform, potentially leading to major changes in the App Store, information, FaceTime, Siri, and other components.
Apple has always emphasized that side-loading functionality could compromise the privacy and security of iPhone users, making them vulnerable to malicious software, scams, data tracking, and other issues. However, Apple must comply with the regulations of the DMA, or else it could face fines of up to 20% of its global revenue.