Signitives IT Solutions Mobile Developer Interview Questions and Answers

Concurrency in Swift can be handled using Grand Central Dispatch (GCD) and Operation Queues.

• Use GCD to perform tasks concurrently by creating dispatch queues.

• Use Operation Queues to manage and execute multiple operations concurrently.

• Avoid race conditions by using serial queues or synchronization techniques like semaphores or locks.

iOS app distribution methods include App Store, Ad Hoc, Enterprise, and TestFlight.

• App Store distribution is for public release and requires Apple's review process.

• Ad Hoc distribution allows sharing apps with a limited number of devices.

• Enterprise distribution is for in-house apps within a company.

• TestFlight is for beta testing with external testers before App Store release.

I am a Senior Android Developer with 5+ years of experience in developing mobile applications for various industries.

• Developed and maintained multiple Android applications from concept to deployment

• Proficient in Java, Kotlin, and Android SDK

• Experience with RESTful APIs, third-party libraries, and version control systems like Git

• Strong problem-solving skills and ability to work in a team environment

• Familiar with Agile d

Higher order function is a function that can take other functions as parameters or return functions as results.

• Higher order functions can be passed as arguments to other functions.

• Higher order functions can return functions as results.

• Examples include map, filter, and reduce functions in functional programming.

The inline keyword is used in Kotlin to suggest that a function should be inlined at the call site.

• Used to eliminate the overhead of function calls by copying the function code directly at the call site

• Helps in improving performance by reducing the function call overhead

• Should be used for small functions or lambdas to avoid unnecessary function call overhead

Agile methodology is a project management approach that emphasizes flexibility, collaboration, and iterative development.

• Agile methodology focuses on delivering working software in short, iterative cycles called sprints.

• It values customer collaboration and responding to change over following a strict plan.

• Key principles include individuals and interactions over processes and tools, working software over comprehensive d...read more

Virtual DOM is a lightweight copy of the actual DOM, used for efficient updates in React applications.

• Virtual DOM is a concept in React where a lightweight copy of the actual DOM is created.

• It allows React to efficiently update the UI by comparing the virtual DOM with the actual DOM and only making necessary changes.

• This helps in improving performance by reducing the number of direct manipulations to the actual DOM.

• For...read more

call, bind, and apply are methods used to manipulate the context of a function in JavaScript.

• call - calls a function with a given 'this' value and arguments provided individually.

• bind - creates a new function that, when called, has its 'this' keyword set to the provided value.

• apply - calls a function with a given 'this' value and arguments provided as an array.

MVVM (Model-View-ViewModel) is a design pattern used in Swift to separate the user interface logic from the business logic.

• MVVM divides the code into three main components: Model, View, and ViewModel.

• Model represents the data and business logic of the application.

• View displays the data and interacts with the user.

• ViewModel acts as a mediator between the Model and View, handling the logic for the View.

• MVVM helps in maki...read more

Multithreading is the ability of a CPU to execute multiple threads concurrently, allowing for improved performance and responsiveness in applications.

• Multithreading allows multiple tasks to be executed simultaneously on a single CPU core.

• It can improve performance by utilizing idle CPU time for other tasks.

• Examples include running background tasks while the main thread handles user interactions in an iOS app.

Data class in Kotlin is used to represent a simple data container with automatically generated methods like equals(), hashCode(), toString(), and copy().

• Data classes are declared using the 'data' keyword before the class keyword.

• Properties of data classes are automatically generated component functions for destructuring declarations.

• Data classes cannot be abstract, open, sealed, or inner.

• Example: data class User(val na

ViewModel is a class that stores and manages UI-related data in a lifecycle-conscious way. MVVM is an architectural pattern that separates the UI from the business logic.

• ViewModel is part of the Android Architecture Components and is used to store and manage UI-related data in a lifecycle-conscious way.

• ViewModel survives configuration changes such as screen rotations and retains its data.

• MVVM stands for Model-View-View...read more

Coroutines are a way to perform asynchronous operations in Android, securing app data involves encryption, SSL pinning enhances security, FCM for notifications.

• Coroutines are used for managing asynchronous operations in Android, allowing for efficient and non-blocking code execution.

• Securing app data involves using encryption techniques such as AES to protect sensitive information from unauthorized access.

• SSL pinning i...read more