The Swift programming language is the culmination of Apple's experience and research on programming languages. Combined with SwiftUI, the process of both prototyping and developing iOS, watchOS, and OS X apps for the Apple landscape has never been more straightforward.
Apple designed and developed Swift to work specifically with their hardware; the result is evident in the performance advantages seen in Swift apps. Swift code also boosts security by eliminating risky code classes, which helps to create a protected environment. In 2015 Apple chose to make Swift open source, proving their commitment to working with the coding community.
Developing Swift apps in XCode is a very interactive process streamlined for working collaboratively. When used in tandem with SwiftUI, designers, and the front end, developers can quickly present functional prototypes to clients for review. SwiftUI makes it easier to manage themes for different devices and enables users' changes in dark mode. SwiftUI code is cleaner and easier to read than UIKit. If any requirements can't be met with SwiftUI alone, UIKit can work alongside SwiftUI using UIHostingController.
Here are some of the major iOS apps all built with Swift.
Swift for iOS helped us form a good foundation for our new iOS mobile app. It is flexible and easy to work with. – iOS Developer, Third Party Consulting Firm