GeeksForGeeks IOS Developer Interview Questions and Answers

Questions about basic Swift knowledge and past work experience.

• Basic Swift concepts such as optionals, closures, and protocols may be asked.

• Questions about past projects and how you approached problem-solving may also be asked.

• Examples of past work experience and projects may be requested.

• Questions about Swift syntax and best practices may be asked as well.

Clean coding principles ensure code readability, maintainability, and scalability.

• Use meaningful variable and function names

• Keep functions short and focused

• Avoid code duplication

• Follow SOLID principles

• Write unit tests

• Refactor regularly

Objective-C is the older language used for iOS development, while Swift is the newer, more modern language.

• Objective-C is a superset of C with Smalltalk-style messaging syntax.

• Swift is more concise and easier to read than Objective-C.

• Swift is safer due to its optionals and type interference features.

• Objective-C has been around longer and has a larger codebase, but Swift is becoming more popular.

• Many developers prefer S...read more

Encryption and decryption in Swift involves using cryptographic algorithms to encode and decode data securely.

• Use common encryption algorithms like AES or RSA for encryption.

• Implement encryption using libraries like CommonCrypto or CryptoSwift.

• Store encryption keys securely and use secure protocols for data transmission.

• Example: Encrypting a string using AES encryption in Swift.

Keychain access in Swift allows secure storage of sensitive information like passwords, tokens, etc.

• Use Keychain Services API to securely store and retrieve sensitive data.

• Keychain items are stored securely in the device's keychain and are encrypted.

• Access keychain items using unique identifiers called keys.

• Use Keychain Swift library for easier implementation.

Classes are reference types, while structs are value types in Swift.

• Classes are reference types, meaning they point to the same instance in memory when assigned to a new variable.

• Structs are value types, meaning they create a new copy when assigned to a new variable.

• Use classes for complex data structures or when you need inheritance, use structs for simple data types or when you want value semantics.

• Example: class Per...read more

Grand Central Dispatch (GCD) is a technology in Swift for managing concurrent operations.

• GCD allows developers to perform tasks concurrently without having to manage threads manually.

• It provides a high-level API for managing tasks and executing them on different queues.

• Developers can use GCD to perform tasks in the background, update the UI on the main thread, and more.

MVVM focuses on separation of concerns by introducing a ViewModel layer, while MVC combines the responsibilities of the Model and Controller.

• MVC stands for Model-View-Controller, where the Model represents the data, the View displays the data, and the Controller handles user input and updates the Model.

• MVVM stands for Model-View-ViewModel, where the ViewModel acts as an intermediary between the View and the Model, hand...read more