Haven't seen it explicitly called out, but if you wanna write a full-featured visionOS app with UIKit & Objective-C, it all still works natively and takes full advantage of the system. You need to use a few lines of Swift/SwiftUI if you want to present ornaments (floating toolbars), or if you want to do anything 3D like view transforms or integrating 3D content. And if you want to make a volumetric or immersive (VR) app, you need to move to the SwiftUI app lifecycle. But ObjC codebases are a go