If you are probing for iOS Interview Questions and looking for an ideal post for the same, Coding Tag offers you the list of Top 30 iOS Interview Questions.





1) What are the different methods used for attaining concurrency in iOS?

The three different methods to attain concurrency in iOS are:

Threads

Dispatch queues

Operation queues

2) Name and explain the framework used to build the application's user interface for iOS?

The UIKit framework is used to construct an application's user interface. It facilitates features such as event handling, windows, drawing model and entire controls particularly constructed for a touch screen interface.

3) List some features of iOS 8?

Battery usage indicator

New keyboard(s)

Continuity

Advanced camera features

iCloud photo library

Interactive notifications

Messages upgrade

iCloud drive

Full-featured safari

The weather channel

4) What is the latest version of iOS?

12.1.4

5) Differentiate between iOS and Android?

iOS Android iOS was developed by Apple Inc. on July 29, 2007

Android was developed by Google, Open handset alliance on September 23, 2008

iOS is available in 34 languages

Android is available on 90+ languages

Complexity in transferring data. Photos can be easily transferred through USB but to transfer media files, there is a need of iTunes desktop app

Photos can be easily transferred via USB port and Android File Transfer desktop app

Siri is available for voice command

Google Now and Google Assistant are the voice commands available in Android.

The initial version of iOS was iOS 1.0

The initial version of android was Android 1.0, Alpha

6) What's Code Coverage?

It is a feature introduced by Xcode, which acts as a metric for measuring the unit test's value and for indicating the execution of tested code.

7) What do you mean by Adapter Pattern?

An Adapter permits working of the classes with incompatible interfaces through wrapping itself with an object and to become an interface for interacting with that particular object.

8) What are the basic Pre-Requisites for learning IOS?

9) List some functions that can be performed with XCODE?

Projects creations and its management

Manage entire project dependencies

App development through project

Smart editors can be used to write source code

Documentation and program file navigation

Restoring an app on iOS simulator

Performance evaluation

10) What do you mean by Xcode?

Xcode is IDE consists of iOS SDK that permits extending Xcode and includes entire advanced features, tools, frameworks, and compilers, that are required to design or debugging any app precisely for iOS development.

11) Is Apple Simulators are available for windows OS?

No

12) What do you mean by the UI view controller?

The UI view controller is a class containing a set of methods used to view hierarchy and its management. These methods are automatically called by iOS at the appropriate time during view controller transitions.

13) List some advantages of Swift?

Closures

Built-in error management

Crash-resistant features

Faster

14) What do you mean by Simulator and its role in iOS?

Simulators are used in iOS for testing objectives. It is included on Xcode that provides the behavior ideas and appearance of the application running on a particular device.

Simulators are used during the building and execution of app on iOS.

15) Which keyword can be used to declare any constant in Swift?

Let keyword

16) What is the role of Sandbox in iOS?

Sandbox contains a range of fine-grained controls used to limit file access. It is used in iOS during installation for data security purposes.

17) What do you mean by App Bundle in iOS?

During iOS App creation, Xcode makes a bundle that acts as a directory located in the file system containing interconnected identical resources together including executable files, and entire supporting files of the application such as image files, content location, icons, etc.

18) Can delegate be retained in iOS?

No

19) List any four support features of UI Kit?

Content encapsulation

PDF creation

Disabled users access to support

Cut, copy, paste, printing and push notification support

20) What are the main concepts used in the memory management of iOS?

Voluntarily memory free-up principle

Virtual memory concepts

ARC

MRC

Reference types

Value types

Weak references

Unowned references

21) What do you mean by the Auto layout?

Auto layout is one of the schemes in iOS used to create scalable UI which is compatible with multiple devices of different sizes and shapes.

22) Describe some key functions of the managed object context in iOS?

Life-cycle management

Concurrency

Notifications

23) What is iOS?

iOS (iPhone OS) is a mobile-based operating system developed by Apple Inc. and circulated entirely for Apple hardware.

Some of the features of iOS are below :

Integrated search support permits instantaneous search via media, applications, files, and email

Gesture recognition supports

Interactive notifications

Google Maps direction services.

24) Explain plist in iOS?

plist stands for Property List i.e. more convenient format used for storing data of the application. It was initially developed by Apple for iPhone users and then later spread in different applications.

The main objective of plist is to organize and structure data. It doesn't store identical data. plists are applicable for Mac OS X and iOS operating systems.