Answer:- Synchronous can also be defined as In order. When you perform the synchronous operation, all that follows must wait for the operation to complete before proceeding. In contrast, “asynchronous” can also be defined as “out of order.” When you do something asynchronously, you can run the following code right away, and the asynchronous process will happen someday. It could be run on a separate thread from the rest of the code. It could easily be rescheduled on the same thread at a later date and you can notify you when it is done.

Answer:- State transitions can be responded to state changes in an appropriate way by calling corresponding methods on the app’s delegate object. For example: • applicationDidBecomeActive( ) method: To prepare to run as the foreground app • applicationDidEnterBackground( ) method: To execute some code when the app is running in the background that may be suspended at any time • applicationWillEnterForeground( ) method: To execute some code when the app is moving out of the background • applicationWillTerminate( ) method: Called when the app is being terminated

Answer:- The process of adding new operators and changing existing ones to do various things is known as operator overloading. +, *, and / symbols are known as operators.

Answer:- TVMLKit serves as a bridge between TVML, JavaScript, and your native tvOS software. You can test TVMLKit JS and TVML files from inside your tvOS app using the TVMLKit framework. The JavaScript environment can be used to build TVML objects, styles, views, and view controllers.

Answer:- The visual elements that we can see in our applications are known as UI elements. Some of these components, such as buttons and text fields, respond to user interactions, while others, such as images and labels, provide information.

Answer:- Swift is a modern programming language created by Apple for iOS, OS X, watchOS, and tvOS apps that combines the best of C and Objective-C, but without the C compatibility issues. Swift follows secure programming patterns while also incorporating modern features to make programming simpler, more versatile, and enjoyable. Swift is welcoming to novice programmers and feels familiar with Objective-C developers. The primary programming language for writing applications for OS X and iOS is Objective-C. It’s an object-oriented programming language with a dynamic runtime that’s a superset of the C programming language. Objective-C takes C’s syntax, primitive types, and flow control statements and adds class and process definition syntax.

Answer:- The NSError class is a Cocoa class. The knowledge about an error condition is encapsulated in an extendable, object-oriented manner by an NSError object. It includes a predefined error domain, a domain-specific error code, and a user details dictionary with application-specific data.

Answer:- The following features are added in iOS 9: • Intelligent search: It is an excellent mechanism to learn user habits and act on that information—open apps before we need them, make recommendations on places we might like, and guide us through our daily lives to make sure we’re where we need to be at the right time. • Siri: It is a personal assistant to the users that is able to create contextual reminders and search through photos and videos in new ways. Swiping right from the home screen brings up a new screen that houses ‘Siri Suggestions,’ putting favorite contacts and apps right on our fingertips, along with nearby restaurant and location information and important news. • Deeper search capabilities: It can show results such as sports scores, videos, and content from third-party apps, and we can even do simple conversions and calculations using the search tools on our iPhone or iPad. • Performance improvements: The following built-in apps have been improved: o Notes including new checklists and sketching features o Maps now offering transit directions o Mail allowing for file attachments o New ‘News’ app that learns our interests and delivers relevant content we might like to read o Apple Pay being improved with the addition of store credit cards and loyalty cards o ‘Passbook’ being renamed to ‘Wallet’ in iOS 9 • San Francisco font • Wireless CarPlay support • Optional iCloud Drive app: It is a built-in two-factor authentication system with optional longer passwords for better security.

Answer:- The following features are added in iOS 9: • Intelligent search: It is an excellent mechanism to learn user habits and act on that information—open apps before we need them, make recommendations on places we might like, and guide us through our daily lives to make sure we’re where we need to be at the right time. • Siri: It is a personal assistant to the users that is able to create contextual reminders and search through photos and videos in new ways. Swiping right from the home screen brings up a new screen that houses ‘Siri Suggestions,’ putting favorite contacts and apps right on our fingertips, along with nearby restaurant and location information and important news. • Deeper search capabilities: It can show results such as sports scores, videos, and content from third-party apps, and we can even do simple conversions and calculations using the search tools on our iPhone or iPad. • Performance improvements: The following built-in apps have been improved: o Notes including new checklists and sketching features o Maps now offering transit directions o Mail allowing for file attachments o New ‘News’ app that learns our interests and delivers relevant content we might like to read o Apple Pay being improved with the addition of store credit cards and loyalty cards o ‘Passbook’ being renamed to ‘Wallet’ in iOS 9 • San Francisco font • Wireless CarPlay support • Optional iCloud Drive app: It is a built-in two-factor authentication system with optional longer passwords for better security.

Answer:- KVC (Key-Value Coding) is a method for accessing an object’s properties using strings at runtime rather than needing to know the property names statically at development time. KVO (Key-Value Observing) allows a controller or class to monitor changes in a property value. In KVO, an object may request to be informed of any adjustments to a particular property, and the observer is automatically notified if that property’s value changes.

Answer:- ou will experience a few app states while using the application. There are five states in the ios application as follows. • Not Running The application is in the Not running state, if the app is not launched yet or if the application is not visible on the screen or also there is the possibility that the application is terminated by the user or by OS. • Inactive An inactive state occurs when the application is not receiving events but the app is running in the background. An app transitions to a different state. when the user locks the screen or the system prompts the user to respond to some event such as a phone call or SMS message is the only time it stays inactive. • Active In an ios application, Active State is the main executive state. In this state, the app is running in the foreground and the UI is accessible. • Background Before being suspended most of all apps enter this state. If an app requests extra execution time then that will remain in this state for some more time. Also, an application will be launched directly into the background enters this background state instead of the inactive state • Suspended In a suspended state the application does not execute any code. The system purges suspended apps without any notice to make more space for the foreground app when a low-memory condition occurs.

Answer:- At runtime, Dynamic Dispatch determines which implementation of a polymorphic procedure, such as a method or a function, to call. This means that when we want to call our methods, such as object methods, we must use this syntax. Swift, on the other hand, does not use dynamic dispatch by default.

Answer:- The GCD stands for Grand Central Dispatch. It is a low-level API that allows you to manage multiple concurrent operations. It will assist you in increasing the responsiveness of your app by deferring computationally intensive tasks to the context. It’s a simpler concurrency model than locks and threads to deal with.

Answer:- • To handle all of the work, only a small amount of code is needed. • Available in both Object C and Swift. • SQLite and Core Data have slower performance. • Database files can be shared easily between iOS and Android devices. • There is no fee, no charge. • There is no limit to the data amount that can be stored. • Regardless of huge data sets or massive storage, consistent speed and consistency