Apple’s Human Interface Guidelines in 2025 vs 2026: What Has Changed

2026: The Rules Are Clearer With Liquid Glass

The current Human Interface Guidelines for materials make Liquid Glass part of the platform design language, but they are much clearer about where it belongs. 

Apple describes Liquid Glass as a functional layer for controls and navigation, including tab bars and sidebars, that sits above the content. It now explicitly advises developers not to fill the content layer with Liquid Glass and to apply custom glass effects sparingly. 

For app owners, this is good news. Keeping Liquid Glass concentrated around navigation and interactive controls makes it easier to modernise an interface without redesigning every card, panel or content surface simply to look current. 

Readability Has Become a Clearer Priority 

The first year of Liquid Glass made one trade-off impossible to ignore: transparency can create depth, but it can also make text and controls harder to read when the background becomes visually busy. 

Apple’s 2026 guidance now gives much more specific advice around maintaining contrast. Its materials guidance distinguishes between regular and clear Liquid Glass, recommends the regular version when backgrounds could affect legibility, and suggests dimming visually bright media behind highly transparent controls when necessary. 

Apple has also added a system setting that lets users adjust Liquid Glass from ultra-clear towards a much more tinted appearance. Apple’s 2026 software announcement presents this as part of making the interface more focused and approachable. 

The practical lesson is that an app cannot depend on one perfect mock-up. Text, icons and actions have to remain understandable when transparency, contrast and appearance settings change. 

That reinforces a broader UX rule we already use at CAD: accessibility should be part of the interface from the beginning, not added as a final check. Our guide to exceptional UX/UI design makes the same point around contrast, adjustable text and testing. 

2026 Brings the Design Principles Back to the Front 

One of the most interesting additions to the 2026 HIG is not a new visual effect at all. Apple reintroduced its design principles around purpose, agency, responsibility, familiarity, flexibility, simplicity, craft and delight. 

That matters because it reframes what “following Apple’s design guidelines” actually means. An app can use every fashionable system component and still deliver a poor experience if users cannot understand what to do, undo an action, find familiar controls or trust what the software is doing. 

For us, this is the clearest philosophical difference between 2025 and 2026. Last year’s story was dominated by appearance. This year, Apple is spending more time talking about intention, behaviour and the person using the product. 

Layouts Now Have to Adapt to More Than One Kind of iPhone 

The biggest practical change to Apple’s 2026 design landscape is the arrival of iPhone Duo. Apple’s first foldable gives iPhone apps an outer display, a larger inner display, Split View multitasking and several ways of holding or positioning the device. 

Apple’s new HIG page for iPhone Duo repeatedly stresses adaptable layouts. Developers are told to use size classes, safe areas and flexible layouts rather than fixed widths or assumptions tied to a particular display. 

This does not mean designing a completely separate app for every fold angle. Apple’s advice is almost the opposite: build one interface that expands and contracts intelligently as the available space changes. 

That makes the 2026 HIG more relevant to existing business apps than it may first appear. A logistics platform might move from a single job view to a list-and-detail layout. An e-commerce app might use extra space for product comparison. A healthcare or employee-management app might keep navigation visible while showing more detail alongside the main task. 

The important part is not the fold itself. It is the expectation that an interface should respond to the space it has instead of being designed for one fixed rectangle. 

App Icons Have Moved From Reinvention to Refinement 

App icons were another obvious part of the 2025 reset. Apple introduced layered icons designed to work with Liquid Glass and different system appearances. Its current app icon change log shows that the guidance was refined again in June 2026. 

Apple has also updated its design tools and says icons in the latest software are sharper and more defined. The direction has not changed, but the system is maturing. 

For businesses, the sensible takeaway is not to redesign a logo every year. It is to make sure the app icon is treated as a system asset that has to remain recognisable across Apple’s supported appearances, rather than a static square created once and forgotten. 

AI Now Has More Explicit UX Rules 

Another clear 2026 addition is the expansion of Apple’s Generative AI guidance. Apple added recommendations for letting people refine generated results, giving feedback while content is being created, and choosing an appropriate type of model for the experience. 

That sounds technical, but it is really a UX question. If an app generates text, recommendations, summaries or other content, the interface needs to make it clear what is happening and give the user enough control to correct or refine the result. 

For a healthcare product, an AI-generated summary may need clear review before it influences a decision. In an e-commerce product, generated recommendations need an obvious relationship to what the customer is trying to find. In an education app, generated material should be easy to edit, regenerate or challenge. 

The AI itself may sit behind the screen, but the HIG increasingly treats the way people interact with it as part of the product design. 

So, What Has Actually Changed From 2025 to 2026? 

The answer is less dramatic than another visual overhaul, but more important for product teams. 

• Liquid Glass has moved from a headline feature to a design material with clearer limits. 

• Readability and contrast have become more explicit parts of the guidance. 

• Users have more control over how transparent the system appears. 

• Apple has brought its core design principles back into the HIG. 

• Adaptive layout guidance matters more as iPhone now includes a foldable form factor and Split View. 

• App icon guidance has been refined rather than reinvented. 

• Generative AI now has more detailed interaction guidance around feedback, refinement and user agency. 

Put simply, 2025 was about introducing the language. 2026 is about using it responsibly. 

Does Your Existing App Need a Redesign for Apple’s 2026 HIG? 

Not necessarily. 

If your app already uses standard Apple components, responds well to different screen sizes, supports accessibility settings and keeps navigation separate from content, you may not need a wholesale visual redesign. 

The apps most likely to need attention are those built around fixed screen dimensions, heavily customised navigation, low-contrast translucent surfaces, or UI components that only work in one orientation or width. 

In that case, the work is closer to adaptive maintenance than starting again. Our article on mobile app maintenance costs explains why keeping pace with operating-system and interface changes is part of protecting the investment already made in an app. 

What This Means for Businesses Building an App in 2026 

For SMEs, start-ups and self-funded founders, the HIG should not become another checklist of visual trends to chase. 

The more useful lesson is to build around adaptable components, clear hierarchy and familiar behaviour from the start. That gives the product room to survive changes in screen size, accessibility settings and platform conventions without needing a major redesign every time Apple changes direction. 

The same principle applies in more complex sectors. Healthcare and education products benefit from clarity and accessible text. Logistics and workforce platforms need layouts that work in motion, on different screen sizes and with changing amounts of information. E-commerce products need navigation and purchasing journeys that remain familiar even as the interface around them changes. 

Apple’s 2026 HIG is therefore less interesting as a style guide than as a reminder that good interface design should be resilient. 

Frequently Asked Questions 

What are Apple’s Human Interface Guidelines? 

Apple’s Human Interface Guidelines, usually shortened to HIG, are Apple’s recommendations and best practices for designing apps and digital experiences across its platforms. 

What was the biggest Apple HIG change in 2025? 

The biggest change was the introduction of Liquid Glass and the wider visual system around it, including layered app icons, updated navigation, materials, colours and system components. 

What changed in Apple’s HIG in 2026? 

Apple refined Liquid Glass rather than replacing it. The 2026 guidance places more emphasis on selective use of glass effects, readability, user control, adaptable layouts, core design principles and generative AI interactions. 

Is Apple getting rid of Liquid Glass? 

No. Liquid Glass remains part of Apple’s design language. The newer guidance is more specific about where to use it and how to protect legibility. 

Does an existing iPhone app need to be redesigned for 2026? 

Not automatically. Apps that already use adaptable layouts and standard components may need only targeted updates. Fixed layouts, heavily customised controls and low-contrast interfaces are more likely to require work. 

Related Reading 

• Apple’s Liquid Glass Design from WWDC 25 

• iPhone Duo: Designing for Apple’s First Foldable 

• The Top Rules for Exceptional UX/UI Design in App Development 

• Designer VS Developer Handoffs: What We Wish The Other One Knew 

Sources 

• Apple Human Interface Guidelines: Materials 

• Apple Human Interface Guidelines: Design Principles 

• Apple Human Interface Guidelines: Generative AI 

• Apple Human Interface Guidelines: Designing for iPhone Duo 

• Apple WWDC26 Design Guide 

• Apple: iOS 26 and Liquid Glass 

• Apple: 2026 Software Design Refinements