Apple's Worldwide Developers Conference dropped a wave of updates across iOS 19, macOS 16, Swift 6.1, and a surprise hardware reveal. We cut through the keynote theater and focus on the APIs, deprecations, and tooling changes that land in your codebase.
The Headline Numbers
WWDC 2025 opened with Apple citing strong developer ecosystem metrics and immediately pivoting to the software stack. No "one more thing" this year — just dense technical announcements.
- Over 200 new APIs across all platforms
- Swift 6.1 ships with complete concurrency checking on by default
- Xcode 17 gains predictive code completion powered by on-device model
iOS 19 Developer Changes
The UI layer gets a significant overhaul. SwiftUI continues to close the gap with UIKit for complex layouts, and UIKit itself is not being deprecated — Apple explicitly said so.
- New FluidLayout API replaces boilerplate constraint code
- HealthKit now exposes mental health metrics API
- App Intents expanded to support background execution
UIKit is not going anywhere. We remain committed to both frameworks and will continue investing in both. — Apple Engineering
Deprecations to Watch
Several legacy APIs are now formally deprecated and will trigger warnings in Xcode 17. Plan migration paths before they become hard errors in a future OS release.
- UIWebView fully removed — migrate to WKWebView
- NSUserNotificationCenter deprecated — use UserNotifications framework
- Objective-C bridging headers will require explicit opt-in in new projects
