iOS Developer Interview Questions
What's the difference between String? and String! in Swift?
Suggested approach: All Swift developers should be able to nail this one: String? marks an optional string and String! marks an implicitly unwrapped string.
For bonus points, go further: when would you use one rather than the other? If you're stuck, consider talking about how Interface Builder creates its outlets, and why it does it that way.
Estimated difficulty: Easy
See the full list of iOS interview questions
Important notes
- There are over 150 interview questions in the system. Once you've read the question and come up with a suitable answer, try reading my suggested approach and see if it helps you add more detail.
- These questions are not designed to be hard; a good interviewer is more interested in generating discussion that lets your ability and interests shine through.
- If you answer a question with "yes" or "no" you've missed the point – interviewers prefer you to provide reasoning, explanation, or detail, so try to elaborate with examples!
- If you're looking for detailed technical questions about the language, you should try my Swift tests instead – there are multiple challenges that will work your brain hard.
- For a whole series of coding challenges, I wrote the perfect book for you: Swift Coding Challenges.
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