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Carlos Lastres928 words

Xcode 27 Ignores the Liquid Glass Opt Out. What Designers Should Check

If an iPhone app still looks like iOS 18 when it runs on iOS 26, there is a good chance one Info.plist key is doing it: UIDesignRequiresCompatibility. Apple's documentation for that key now ends with this sentence: "The system ignores this key when you build for iOS 27 or later." Xcode 27 has been out since September 14, 2026. So the opt out from Liquid Glass lasts exactly as long as a team keeps building with Xcode 26.

That turns the redesign into a scheduling problem, and schedules are where designers get squeezed.

What the key does

Apple introduced Liquid Glass on June 9, 2025, as one design across iOS 26, iPadOS 26, macOS Tahoe 26, watchOS 26 and tvOS 26. Any app that uses standard SwiftUI, UIKit or AppKit components picks up the new look as soon as it is built with the latest SDK.

For teams that were not ready, Apple added UIDesignRequiresCompatibility. The documentation says that when it is set to YES, "the system runs the app using a compatibility mode for UI elements", which "displays the app as it looks when built against previous versions of the SDKs." The same page tells developers to "temporarily use this key while reviewing and refining your app's UI." The word temporarily was there from the start, and the iOS 27 line now gives it an end date.

The timeline

Three dates matter, and only two of them are announced.

  • Since April 28, 2026, Apple's upcoming requirements page says apps uploaded to App Store Connect must be built with Xcode 26 or later using the iOS 26 SDK or the equivalent for the other platforms.
  • On September 14, 2026, Xcode 27 was released. Build with it for iOS 27 and the compatibility key does nothing.
  • Apple has not announced when Xcode 27 becomes the minimum for uploads. This year the Xcode 26 requirement started in late April, and my own planning assumes something similar in spring 2027. That is my assumption, not Apple's date.

In practice the deadline arrives earlier than the requirement. Engineers move to the new Xcode for its tools, a new API or a fix, and the redesign lands with the upgrade whether or not design was ready for it.

What changes when the opt out goes away

Apple's guide to adopting Liquid Glass is clear about which parts take care of themselves. Bars, sheets, popovers and controls built from standard components adopt the material automatically, and the system adapts them to things like overlapping elements and focus.

The work is in everything custom. The guide asks developers to reduce custom backgrounds in controls and navigation, and names split views, tab bars and toolbars as places to check, because custom backgrounds "might overlay or interfere with Liquid Glass or other effects that the system provides, such as the scroll edge effect." If your design system painted its own tab bar, that is the first screen to look at.

It also says to apply the glass to custom controls sparingly. The material is meant to put attention on the content underneath, and a screen with glass on every custom button ends up distracting from the very thing it is supposed to frame.

What I would check first

This is the list I would run on any app that still ships with the key set, roughly in this order:

  • Every custom tab bar, toolbar and navigation bar. Remove the painted background first and see what the system gives you before designing anything new.
  • Text and icons that sit over content. Translucent bars over photos or bright lists are where contrast fails, so test with real content, not empty states.
  • Accessibility settings. Apple notes that people can pick their preferred Liquid Glass look and can turn on settings that reduce transparency or motion. Test custom colors and animations with each of those on.
  • The app icon. Icons are now layered, with default, dark, clear and tinted variants, and Apple's Icon Composer app builds them from your layers. A flat icon with baked in shadows will look out of place next to the rest of the Home Screen.
  • Screenshots and marketing. If the App Store page shows the old interface, it will stop matching what people install the day the new build ships.

Why I would not wait

An opt out is useful for a few weeks of review. Used for a year, it turns into a pile of design debt that gets paid at the worst moment, inside someone else's release. The teams I see doing this calmly treat the iOS 27 sentence as the brief: build with Xcode 27 on a branch, list what breaks, and fix it on a schedule that design controls.

If you have been holding the key in place because the redesign felt large, it is usually smaller than it looks once the custom backgrounds are gone, because the system components do most of the work. What is left is your custom controls, your colors over content and your icon.

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