Xcode 26.4.1 is now the baseline stable for iOS 26 development, carrying the updated SwiftUI performance instrument introduced in 26, NavigationSplitView container additions, material-aware animations, explicit view invalidation controls, and interactive cell reordering. Live render previews are now first-class, and performance counters in the SwiftUI instrument capture cause-and-effect information about view updates. Developers still on older Xcode builds should upgrade before the April 28 App Store SDK cutoff. The 26.4.1 line is the safe target for submissions — the 26.5 beta with new StoreKit subscription APIs is not yet cleared for production uploads.