Question 1
How would you structure an iOS screen for the main task in this posting?
Approach. Name where state lives and what you would keep off the main thread.
iOS engineer interview questions from a job description
Get the Swift, UI, release, and debugging questions an iOS engineer job description is likely to ask.
Matched in your browser from the requirements in the posting and Luna’s interview-question hub. These are practice prompts, not a claim that this wording will be asked.
Requirements in the posting
iOS Engineer
Build the iPhone app in Swift.
You will:
- Ship screens in SwiftUI and UIKit and explain where state lives
- Handle a slow or failed API without blocking the main thread
- Treat accessibility, including VoiceOver, as part of the feature
- Work within App Store review and release constraints
- Debug crashes and collaborate with backend engineers on the contract
We will ask you to narrate one screen from memory.
Build the iPhone app in Swift.
You will:
- Ship screens in SwiftUI and UIKit and explain where state lives
- Handle a slow or failed API without blocking the main thread
- Treat accessibility, including VoiceOver, as part of the feature
- Work within App Store review and release constraints
- Debug crashes and collaborate with backend engineers on the contract
We will ask you to narrate one screen from memory.
Likely questions
Coding
iOS
Ship screens in SwiftUI and UIKit and explain where state lives
Question 2
What is different about testing an iOS change versus a web change for this team?
Approach. Mention the device or OS split you would actually cover, and the one you would sample.
Coding
Mobile
Work within App Store review and release constraints
Question 3
Which part of this product has to work on a flaky network, and what do you show while it does not?
Approach. Name the offline or retry behavior and the state the user can still trust.
Question 4
How would you ship a mobile change without waiting on a store review for every fix?
Approach. Separate what can be configured from what needs a binary, and say the risk of each.
Role
Accessibility
Treat accessibility, including VoiceOver, as part of the feature
Question 5
Which flow in this job has to work with a keyboard and a screen reader, and how would you check it?
Approach. Name the control, the expected announcement, and the check you would do before shipping.
Question 6
Tell me about an accessibility fix that changed the design, not just the markup.
Approach. Describe the user’s block, the design change, and what you gave up to make the action clear.
System design
Backend services
Debug crashes and collaborate with backend engineers on the contract
Question 7
Where would you draw the service boundary for this product, and what would you keep in one process for now?
Approach. Start from the request that must be fast, then name the split you would postpone.
Question 8
A dependency you call is slow or down. What does this product do?
Approach. Say the user-visible fallback and the failure you will not hide.
System design
APIs
Handle a slow or failed API without blocking the main thread
Question 9
Design the API a client of this product would call first. What is the request, the success, and the error?
Approach. One resource, the idempotency story, and what the user sees on a timeout.
Behavioral
Collaboration
Debug crashes and collaborate with backend engineers on the contract
Question 10
Tell me about a disagreement with someone who did not report to you. What did you do with their objection?
Approach. Name the objection, what you changed, and what you did not. Do not flatten it into “we aligned.”
What to prepare
- Explain one screen’s data flow in Swift without opening a project.
- Practice one mobile constraint out loud: offline, a slow network, or a small screen.
- Tab through one flow with your eyes off the screen and note the first place focus gets lost.
- Draw one service boundary and say what you would not split out yet.
- Write one endpoint on paper: method, body, error, and what a retry should do.
- Have one story where someone disagreed and you kept the working relationship.
- Mark the three requirements you cannot yet support with a story.
iOS postings are specific. Swift, SwiftUI, and UIKit tell you the UI round. Accessibility is a keyboard and VoiceOver question if it is listed as work. App Store and release lines are a constraint story. API lines are the contract with the backend: retry, error, and what the screen shows.
They will ask you to explain a screen’s data flow without the project open, including what stays off the main thread. A crash or performance bullet is a symptom-cause-fix story, not a tour of Instruments.
Prepare one screen you shipped and one platform rule that changed the design. The sample is a Swift product role.
Sample job description
The posting below is already in the tool. The questions are the ones its requirements point to. Replace it with a posting you are actually interviewing for.
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