Key Takeaways from WWDC 2018: iOS, Xcode, Swift, Privacy, and Future Technologies

Trust From User

Apple emphasized the importance of gaining user trust, highlighting stricter privacy description requirements and tighter review policies for vague permission statements.

Privacy Settings

iOS continues to expand privacy permissions; vague descriptions like "to improve user experience" will be rejected, indicating tighter privacy control.

Data Security

WWDC showcased data‑security improvements such as data encryption, stricter ATS, two‑factor authentication, automatic SMS code detection, and password autofill extensions.

macOS Security Enhancements

macOS Mojave introduces more privacy settings and stricter restrictions on apps from un‑notarized developers.

Development Tools

Xcode receives several new features and performance improvements.

Signpost

Apple opened the new API os_signpost and demonstrated using signposts with CPU usage to locate main‑thread bottlenecks (see Session 405).

Source Editor

Improvements include faster large‑file opening, fixed file‑parsing crashes, multi‑cursor editing, code folding, over‑scroll, and better Git integration.

Performance Enhancements

Swift‑based build system is up to twice as fast with 20% lower memory usage.

Device symbol downloads are five times faster.

Parallel testing accelerates UI test suites.

App Store Connect

Apple replaced iTunes Connect with a new platform offering a full RESTful API for app submission, TestFlight management, marketing reports, and account/device/certificate handling.

Dark Mode

Xcode now supports Dark Mode, allowing developers to code in a dark interface.

Future

ARKit 2

Apple announced the largest AR platform with USDZ file format, refined face tracking, environment textures, 3D object detection, AR maps, and shared experiences.

Machine Learning

CoreML adds image processing and NLP APIs; CreateML simplifies model training and compression; Metal optimizes for ML and adds TensorFlow‑for‑Swift support.

iOS Platform

iOS 12 enhances Cocoa Touch with performance improvements, new APIs for iMessage apps, Siri Shortcuts, and Swift optimizations.

Framework Updates

Performance

Scrolling

Apple explained the cell lifecycle (data source, layoutSubviews, draw) and the need to complete all work within a single refresh interval, especially on 120 Hz iPad Pro. Prefetching moved after cell creation for better performance.

Memory

Automatic Backing Store reduces color depth to lower memory usage; APIs like UIView.draw() , UIGraphicsImageRenderer , and UIGraphicsImageRendererFormat.Range are enabled by default.

Auto Layout

iOS 12 optimizes Auto Layout from exponential to linear time for complex constraint graphs.

Swiftification

Swift 4.2 nests enums (e.g., UIApplicationState into UIApplication ), moves global constants into classes, and introduces new conditional compilation directives (#if canImport, #if hasTargetEnvironment, #warning, #error).

NSSecureCoding

Default secure coding is added; older APIs are deprecated (see Session 222).

API Enhancements

Notifications

Custom interactive notifications, grouped notifications, and in‑settings toggles are introduced.

Messages

Message stickers can be placed in the Camera; new Info.plist key MSSupportedPresentationContexts is required.

Automatic Passwords and Security Code AutoFill

iOS 12 improves password autofill, strong password generation, and one‑tap verification code entry.

Safe Area

Developers are urged to adopt SafeAreaInsets for varied device shapes (see Session 235).

Siri Shortcuts

New APIs enable apps to appear in Siri suggestions, Apple Watch faces, and define shortcut intents via NSUserActivity (set eligibleForPrediction = true ) and Intents.

Swift

Swift continues to evolve with community involvement, though it is no longer a WWDC highlight.

Swift Community

Sessions discuss the Swift ecosystem, forums, packages, and encourage contributions.

General Improvements

CaseIterable enums now provide allCases .

Hashable gains hash(into:) for better hashing.

Random number APIs and collection shuffling are added.

New macros: #if canImport, #if hasTargetEnvironment, #warning, #error.

ABI Stability

Swift 5 aims for ABI stability, reducing app bundle size and improving runtime performance.

Tips

External links are not allowed in WeChat; readers must manually follow references.

Recruitment

Liulishuo is hiring iOS engineers to join future WWDC trips; applications should be sent to [email protected].