ref▌

Use when:

iOS provides bit-perfect output by default to USB DACs — no resampling occurs. The DAC receives the source sample rate directly.

Command-line interface for Instruments profiling. Enables headless performance analysis without GUI.

Complete reference for typography on Apple platforms including San Francisco font system, text styles, Dynamic Type, tracking, leading, and internationalization through iOS 26.

Complete reference for converting OpenGL/DirectX code to Metal.

Complete API reference for SpriteKit organized by category.

Use when:

SwiftUI search is environment-based and navigation-consumed. You attach .searchable() to a view, but a navigation container (NavigationStack, NavigationSplitView, or TabView) renders the actual search field. This indirection is the source of most search bugs.

Comprehensive guide to Core Spotlight framework and NSUserActivity for making app content discoverable in Spotlight search, enabling Siri predictions, and supporting Handoff. Core Spotlight directly indexes app content while NSUserActivity captures user engagement for prediction.

Complete API reference for collecting field performance metrics and diagnostics using MetricKit.