This was stated by user X, nicknamed “iSoftware Updates”, referring to the documentation for developers.
For now, apps using the iOS 26 SDK can keep their regular UI. However, with the release of Xcode 27 and iOS 27, Apple will likely remove this feature entirely. The final implementation of the new requirements is scheduled for April 2027; after that date, App Store moderation will reject all apps that do not include Liquid Glass.
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