What's new
Changes to the course: new questions, features and updates for each Swift and iOS release.
: Course launch
iOS Interview Questions and Answers is live: 192 hands-on questions across 16 topics, plus 67 quick facts. Try each one first, then read the answer.
- New: 192 interactive questions across 16 topics, from concurrency and SwiftUI to mobile system design. All questions
- New: 67 quick facts you can read in a few seconds each, mixed in with the topics. All questions
- New: Flashcards and quizzes on every topic page. Concurrency · SwiftUI
- New: Daily 5: five fresh questions a day, the same for everyone, with a result grid you can share. Daily 5
- New: Mock interviews with timed question sets. Mock interviews
- New: Study plans for an interview in 2 days, 7 days or 30 days. Study plans
- New: Weak-spot review brings back the questions you missed or guessed, right when they're due. Weak-spot review
- New: Visualizers you can step through: task timelines, ARC retain counts, memory graphs, queue races and Combine marbles. Sequential await vs async let · How ARC works · Retain cycles and how to break them · Reader-writer with a barrier vs an actor · debounce vs throttle
- New: Printable cheat sheets, one per topic. Cheat sheets
- New: Search across every question and fact as you type. Search
- New: Swift 6.2 concurrency: default MainActor isolation, Sendable, actor reentrancy and Mutex. Swift 6.2: default MainActor and @concurrent · Sendable and Swift 6 strict checking · Actor reentrancy: check, await, then act · Mutex vs actor
- New: Modern SwiftUI data flow with @Observable and @Bindable. @Observable vs ObservableObject · @Bindable for passed-in models · Which property wrapper for which data?
- New: iOS 26 Liquid Glass and the Foundation Models framework. Adopting Liquid Glass in iOS 26 · On-device models with Foundation Models
- New: App Intents, StoreKit 2 and Live Activities. App Intents and Shortcuts · In-app purchases with StoreKit 2 · Live Activities
- New: Every code sample is type-checked with Swift 6.4 in Swift 6 language mode. The snippets that show a compile error really do fail with that error.