Programming languages · Language

Swift

Apple's modern language for apps on iPhone, iPad, Mac, Apple Watch and Apple TV, designed to be fast and safe.

Mobile · Open source · updated

How it works

Apple introduced Swift in 2014 as the successor to Objective-C and made it open source in 2015. It is statically typed and compiles to fast native code, and memory is managed by automatic reference counting (ARC) rather than a garbage collector. Optionals force code to handle missing values explicitly, closing off a common source of crashes.

Nearly all new Apple-platform work is written in Swift, and SwiftUI builds interfaces declaratively in it. Recent versions check concurrent code for data races at compile time, using async/await and actors. Swift also runs on Linux and Windows, with server frameworks such as Vapor, but its community is centred on Apple.

In practice, building and publishing iPhone apps needs Xcode, which runs only on macOS, so a Mac is part of the kit.

Swift pros and cons

Pros

  • The native, Apple-supported way to build for iPhone and Mac
  • Fast compiled code with strong safety features
  • Modern syntax that is pleasant to read and write
  • SwiftUI makes building interfaces quicker

Cons

  • iOS work needs a Mac and Xcode
  • Mostly useful inside Apple's ecosystem
  • Yearly language and SwiftUI changes mean regular code updates

When to use Swift

Pick it when

  • iPhone, iPad and Mac apps that should feel fully native
  • Apps that need new Apple features, such as widgets or Live Activities, as soon as they ship

Skip it when

  • One codebase must also cover Android (consider Flutter, React Native or Kotlin Multiplatform)

Swift pricing

Open source

Free (Apache 2.0). Xcode is free but runs only on a Mac; publishing on the App Store needs the Apple Developer Program at $99 a year.

Swift pricing page (opens in a new tab)Approximate, checked September 2026.What the other tools cost

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