iOS Interview Questions and Answers

Are you a fresher preparing for an iOS developer interview? If so, you’re likely eager to showcase your knowledge and skills in iOS development. To help you ace your interview, we’ve compiled a list of the top 7 iOS interview questions and answers.

Q1. What is ARC in iOS?
Ans: ARC stands for Automatic Reference Counting. It’s a memory management technique used in iOS to automatically manage memory by keeping track of objects’ references.

Q2. What are the key features of Swift programming language?
Ans: Swift is known for its safety, speed, modern syntax, optionals, type inference, and memory management using Automatic Reference Counting (ARC).

Q3. Explain the difference between strong, weak, and unowned references in Swift.
Ans: Strong references keep objects alive as long as there’s at least one strong reference to them. Weak references don’t keep objects alive and automatically become nil when the object they reference is deallocated. Unowned references are similar to weak references but don’t require unwrapping and are used when it’s guaranteed that the referenced object won’t be deallocated before the reference is accessed.

Q4. What is the difference between a delegate and a notification in iOS?
Ans: A delegate is a design pattern used for one-to-one communication between objects, where one object acts on behalf of another object. Notifications, on the other hand, are used for one-to-many communication, allowing an object to broadcast messages to multiple observers without knowing who they are.

Q5. What is a closure in Swift?
Ans: A closure is a self-contained block of functionality that can be passed around and used in your code. It captures references to variables and constants from the surrounding context in which it’s defined.

Q6. Explain the concept of optional chaining in Swift.
Ans: Optional chaining is a process for querying and calling properties, methods, and subscripts on an optional that might currently be nil. If the optional contains a value, the property, method, or subscript call succeeds; if the optional is nil, the call returns nil.

Q7. What are generics in Swift?
Ans: Generics are a way to make your code more flexible and reusable by writing code that doesn’t depend on specific types. They allow you to write functions and types that can work with any type.