iOS Interview Questions
  1. Explain the Adapter and Memento Pattern?
  2. Can you explain completion handler?
  3. What do you do when you realize that your App is prone to crashing?
  4. Explain Core Data.
  5. Explain the Grand Central Dispatch (GDC).
  6. Explain MVC structure.
  7. How is memory management handled in iOS?
  8. What do you know about singletons? Where would you use one and where would you not?
  9. What’s different between delegate and KVO?
  10. What are design patterns besides common Cocoa patterns that you know?
  11. What options do you have for implementing storage and persistence on iOS?
  12. What options are available for networking and HTTP on iOS?
  13. How and when to serialize and map data on iOS?
  14. What are the options for laying out UI on iOS?
  15. How to optimize scrolling performance of dynamically sized table or collection views?
  16. How would you execute asynchronous tasks on iOS?
  17. How do you manage dependencies?
  18. How do you debug and profile code on iOS?
  19. Do you have TDD experience? How do you unit and UI test on iOS?
  20. What different between mocks, stubs, and fakes?
  21. What is FRP (Functional Reactive Programming) and its place in iOS platform?
  22. What iOS architectures do you know that scale?
  23. How would you create a HTTP request in iOS?
  24. How would you send and receive HTTP requests in iOS?
  25. In iOS, a networking feature called App Transport Security (ATS) requires that all HTTP connections use HTTPS. Why?
  26. How would you convert a JSON response into native Swift types?
  27. Do you have experience with third-party iOS networking libraries? If so, which ones?
  28. Explain main thread and it’s usages
  29. What is serial queue?
  30. What is concurrent queue?
  31. What is priority inversion?
  32. What is concurrency and time slicing?
  33. What is NSOperation?
  34. What is NSBlockOperation?
  35. What is semaphore?
  36. Do your need weak or unowned for UIView animation?
  37. When should you use frame/bounds?
  38. What is an unwind segue?
  39. What is intrinsic content size?
  40. What’s the difference between a xib and a storyboard?
  41. What is difference between layout margins and directional layout margins ?
  42. What is Safe area ?
  43. What is reuseIdentifier in UITableView/UICollectionView?
  44. What is NSLayoutAnchor ?
  45. What is ARC ?
  46. What is circular dependencies ?
  47. What is a retain cycles?