Some iOS interview questions I've come accross

iOS Interview questions.md

##iOS interview questions ###UIKit

1. Walk me through setting up a table view.
2. What is the difference between a UITableViewController and a UIViewController with a table view? When would you use one over the other?
3. Briefly explain the view controller lifecycle.
4. What does an application's AppDelegate subclass? By default, what protocol does it implement? Name some of those delegate functions?
5. What is your favorite UIKit API?
6. What type of UICollectionView layouts have you used?
7. Have you ever written your own custom control? What was it? Why did you need to use that instead of a standard one?
8. Name something you could present in a UIViewController that is not a subclass of UIView.
9. Explain how delegation works.
10. Explain the difference between delegation and notification.
11. Explain a situation when a custom delegate could be used. Walk me through the setup.

###Swift

1. Briefly explain optionals.
2. What are generics? How are they used?
3. What is the difference between a class and a struct? Why would you use one over the other?

###ARC

1. Briefly explain how ARC works?
2. What is the difference between a strong and a weak reference.
3. What is a memory leak? Explain how one could occurr.
4. What is a retain cycle?

###Other

1. What is Grand Central Dispatch? How + Why is it used?