IOS Development Interview Questions

After months of testing, Apple iOS 11 is now available to the public. Apple provided a preview of the iOS 11 features at the Worldwide Developers Conference (WWDC) in June 2017. There were 10 betas released for developers before the final version was released today. The iPhone 8S, 8S Plus and iPhone X devices — which were announced on September 12th — ship with iOS 11. Amit Chowdhry iOS 11 download screenshot In terms of design, there are not many significant differences between iOS 10 and iOS 11. But there  are dozens of new features baked into iOS 11, of which you can find  42 of the best in my earlier article .  So what is included in the update? Here is an overview of the primary iOS 11 features: ARKit Apple Apple AR app A new augmented reality (AR) framework called ARKit enables developers to build apps with immersive AR experiences for devices that support iOS 11 and above. ARKit essentially blends digital objects and content wi...

Apple’s WWDC 2017 is just under way, and we already have some great news for developers! What I liked the most in the Platforms State of the Union keynote is the improvements made around Xcode. So I decided to put together my personal top 5 of what I am looking forward to playing with in Xcode 9. Note that the new Xcode editor has been completely re-written from scratch in Swift, which makes it much faster in a lot of areas 🎉 1. Refactoring in Swift 🔨 Ahh finally! This is something I was expecting since as long as Swift has been around, and they finally delivered! Gone are the  Cmd + Shift + F  where you miss out on a few variable rename, or accidentally modify an unrelated one. Gone are the cut + paste + modify to extract methods. We finally have access to those! Although there’s still a long way for Xcode to offer advanced refactoring tools like JetBrains does today, it offers the most common ones like adding code snippets, extracting methods and variables, an...

Key Steps to Delegation The  delegation design pattern  has long been a core competency for Cocoa programmers. This remains the case with the arrival of Swift. Regardless of whether you are using Objective-C or Swift the basic steps to use delegation are the same: Create a delegate protocol  that defines the responsibilities of the delegate. Create a delegate property  in the delegating class to keep track of the delegate. Adopt and implement  the delegate methods in the delegate class. Call the delegate  from the delegating object. Note that there are a couple of differences between Swift and Objective-C support for delegates: Swift allows protocols to be used by classes, structs or enums. In Objective-C we are limited to classes. This changes whether we use reference semantics (classes) or value semantics (structs and enums) for the delegate. Objective-C supports optional protocol methods. Swift only allows optional protocol requirements if...

Memory management is very important in any application, especially in iOS apps that have memory and other constraints.It refers to ARC, MRC,  reference types , and  value types .This is a must know for every iOS developer! Memory leaks and app crashes are all too common due to poorly managed memory in iOS apps. Swift uses  Automatic Reference Counting (ARC) . This is conceptually the same thing in Swift as it is in Objective-C.  ARC  keeps track of strong references to instances of classes and increases or decreases their reference count accordingly when you assign or unassign instances of classes (reference types) to constants, properties, and variables. It deallocates memory used by objects which reference count got down to zero.  ARC does not increase or decrease the reference count of  value types  because,  when assigned, these are copied. By default, if you don’t specify otherwise, all the references will be strong references. O...