The whole handbook, free.
537 interview questions for iOS 27, Xcode 27 and Swift 6.4, plus guides for Git, Agile, Instruments, debugging, AI tools and Cloudflare, and Xcode playgrounds. PDF and EPUB, no catch.
What’s inside
Every answer was rewritten for the current platform: Swift 6 concurrency, Observation, SwiftData, Swift Testing, Liquid Glass, resizable apps and iPhone Duo, and Apple Intelligence.
swift-fundamentals/55 filesValue Types vs Reference Types, Noncopyable Types (~Copyable), InlineArray and Span…uikit-views/59 filesView Lifecycle, Automatic Observation Tracking, Auto Layout…swiftui/56 filesObservable Macro, @State, @Binding, @Bindable, and (legacy) @ObservedObject, @StateObject vs @ObservedObject…architecture/53 filesMVC, MVVM, VIPER…networking/54 filesURLSession, A Networking Layer for Swift 6 Strict Concurrency, Codable and JSON…concurrency/54 filesasync/await, MainActor, Approachable Concurrency (Swift 6.2)…memory-performance/52 filesRetain Cycles, ARC, Instruments…data-persistence/50 filesUserDefaults, When to Use UserDefaults, Data Modeling for Mobile…testing/54 filesUnit Testing, Mocking and Stubbing, UI Testing…system-design/50 filesImage Caching System, Scalable Chat App, Feed Loading (Instagram-style)…
537 questions · 10 topics+ guides: Git, Agile, Instruments, debugging, AI tools, Cloudflare · Xcode playgrounds
Code you can trust in an interview.
All 798 Swift blocks in the book are compiled in Swift 6 mode against the iOS 27.1 SDK, at iOS 26 and 27, both as plain code and with the default MainActor isolation new Xcode 27 apps use. Shortcuts like try? or force unwraps either got fixed or carry a comment saying why they’re safe.
verify/report798 blocks
1added: 754 compile clean in all four configurations
2added: 7 use iOS 27 APIs, tagged in the text
3added: 20 labelled bad examples, failing exactly as described
44 17 third-party packages, checked by reading