Later This Month
Last year’s Liquid Glass UI rework brought by iOS 26 was challenging. The transparency effects required rethinking how your app layers controls, and most of the new frameworks were broken or buggy. This is the first year, as an independent app developer, that I’ve prepared multiple apps for multiple platforms, and so far, this year’s iOS 27 beta releases have been much easier to work with. iOS 27 is refinement instead of a rethink. The same Liquid Glass design language is more mature, and the SwiftUI frameworks have had a year of improvements. It has all been going so well. Then, Apple released iPhone Duo, with a unique form factor.
On the Duo, toolbars and tab bars go vertical and move to the side of your app — but not all of them, and not all the time. There are approximately six distinct layout modes, plus new aspect ratios for every split view configuration. The device reports its hinge angle to your app so you can move controls out of the crease, where they’re hard to reach. And there are now safe areas on the left and right edges of the screen. Those have existed in the API since the iPhone X but have always been zero. Every layout decision I’ve made for my apps depended on an assumption that is now incorrect.
For the past year, developers have complained about the toolbar API that makes you declare a control’s role — primary, secondary, tertiary — instead of its position. It felt like Apple being punitive for no reason. It was for this. The system needs to decide placement per pose, and it can’t do that if you’ve told it “put this in slot two.” Apple knew this was coming and never provided additional guidance to developers.
Of course, none of that helps if you wrote custom toolbar code to work around the semantic API. Which many of us did, because the stock controls only fit a basic app. The SDK I need to build for it is still unreleased as of the publish date of this article, which leaves whatever remains of six weeks to redesign apps I haven’t yet been allowed to open in a simulator.
Apple is better positioned than any company in the industry to make this transition painless. It designs the hardware, the operating system, the frameworks, and the tools, and it has said for decades that this integration is the point — that owning every layer is what lets it deliver experiences nobody else can. It’s the reason the Duo can exist at all. But the SDK is late and the phone is coming. A toolbar that relocates itself across six layout modes is a rewrite, not a quick recompile. A device whose hinge angle is an input to your UI is a device you have to hold. Apple has known this phone was coming for years. Developers got six weeks, minus however Apple defines “later this month.”
Writing software for a company this accustomed to complete platform control will always be a lesson in power imbalance. I knew that before writing my first line of Objective-C code years ago. Apple could have shipped the tools with the announcement. Instead, it gave an announcement, and the first real test of my layouts will happen on a customer’s phone.