Top iOS Interview Questions [2023]
iOS developers build applications for mobile devices powered by the iOS operating system. They build, test, and refine mobile applications for Apple iOS. Interviewing iOS candidates commonly consists of basic and advanced questions to assess technical ability. We sourced these questions from the iOS community based on developers’ own interview experience and what our clients found important to ask. Could you use help hiring iOS developers? Scalable Path’s experienced Talent Acquisition team can help.
iOS Interview Questions and Answers
These are the types of questions typically asked during iOS interviews. We created them to help you test your understanding of the popular programming language, or guide your initial technical screening with iOS candidates.
How would you explain closures to a new Swift developer?View Answer
State the difference between App ID and Bundle IDView Answer
Explain how the Apple Developer Program membership uses certificates.View Answer
Explain your experience with Accessibility tools on iOSView Answer
Explain Mac Catalyst, its functionality, and give your thoughts on the overall integration between Apple’s operating systems.View Answer
Please describe the four layers of the iOS architecture, and briefly explain the role of each layer. Think of the hardware as the bottom layer.View Answer
Please list the possible states in which an iOS application can be. For each state, list the states to which the app can transition.View Answer
What is ARC in the Swift programming language, what is it for, and how does it work?View Answer
What is a lazy variable? Explain how they work.View Answer
What does KVO mean? What considerations must be taken on Swift to achieve it?View Answer
What is a phantom type in Swift? What are they for?View Answer
What is Display P3, and what considerations should be taken with your assets and code when your app supports wide gamut displays?View Answer
What does deep linking mean on iOS? What are your options to implement deep links, and what are the differences?View Answer
What is the difference between self and Self in Swift? What are the main uses of both?View Answer
What is a variadic function, and how do you implement one in Swift. How would you make a variadic function that accepts multiple types?View Answer
Explain the difference between argument labels and parameter names in function parameters. Is it possible to write a function without a label? If so, how? Is it possible to write a function without a name? If so, how?View Answer
Explain a common use case for the targetEnvironment() compilation condition and write a snippet of a conditional compilation block of code (you may omit statements and simply use comments inside the block)View Answer
Describe the workflow for configuring in-app purchasesView Answer
Describe the differences and relationship between RealityKit and ARKitView Answer
Explain the three phases of implementing Handoff in your app.View Answer
This list isn't exhaustive, and interviewing typically includes an assessment of soft skills and technical ability through a take-home assignment or live coding exercise. You can learn more about hiring here.
