Top 6 Ios Interview Questions
Browse 6 real-world technical and behavioral interview questions about Ios. Review scenarios, edge cases, and architectural best practices.
A deep link opens the right screen when the app is in the background and the wrong one when the app was killed. How do you test for that?
Treat each launch state as its own test case, because each delivers the link through a different code path. Cold start runs splash, auth and initialisation that can drop the link, and on iOS delivers it in the scene's connection options, not the continue callback. Test cold, warm, restored and logged-out.
How do you choose which devices to test on, and what will an emulator never tell you?
Pick devices from your own analytics rather than from a market-share article, spread the choice across OS version, screen size, memory class and manufacturer skin, and keep real hardware for anything involving the camera, sensors, radios, battery or vendor-modified behaviour.
You're asked to break up a five-year-old iOS app that has become one enormous Xcode target - how would you approach modularising it, and what does it cost you?
Modularising means carving the app into Swift packages along feature and layer boundaries so build graphs and ownership become explicit, at the cost of slower initial builds, careful dependency direction, and real discipline about what each module exposes publicly. Use this IOS answer to show the decision, trade-off, and evidence rather than a memorised definition.
How do you design the dependency graph, handle shared resources, and optimise build times when breaking down a massive iOS monolithic application into a modular architecture using Tuist?
Assess the candidate's ability to migrate a large-scale iOS application to a modular architecture using Tuist, managing dependency graphs, enforcing architectural boundaries, and optimising build times. Use this MOBILE answer to show the decision, trade-off, and evidence rather than a memorised definition.
How do retain cycles happen in Swift closures and delegates, and how would you find one in an app that is slowly leaking memory?
A closure or delegate reference that captures its owner strongly, while the owner also holds that closure or delegate strongly, forms a cycle ARC cannot break on its own, and the fix is weak or unowned capture chosen by lifetime, not by habit. Use this IOS answer to show the decision, trade-off, and evidence rather than a memorised definition.
Your SwiftUI screen redraws constantly and scrolling stutters - how would you find out why, and what state-management mistake usually causes it?
A re-render storm usually comes from one large ObservableObject whose @Published properties fan out too widely, so any single field change invalidates every view reading the object rather than just the row that changed. Use this swiftui answer to show the decision, trade-off, and evidence rather than a memorised definition. It also connects state management to the point an interviewer is testing.