Kotlin
Kotlin

1.5K
1K
234
Swift
Swift

4.6K
2.9K
1.1K
Add tool

Kotlin vs Swift: What are the differences?

Kotlin: Statically typed Programming Language targeting JVM and JavaScript. Kotlin is a statically typed programming language for the JVM, Android and the browser, 100% interoperable with Java; Swift: An innovative new programming language for Cocoa and Cocoa Touch. Writing code is interactive and fun, the syntax is concise yet expressive, and apps run lightning-fast. Swift is ready for your next iOS and OS X project — or for addition into your current app — because Swift code works side-by-side with Objective-C.

Kotlin and Swift can be primarily classified as "Languages" tools.

"Interoperable with Java" is the primary reason why developers consider Kotlin over the competitors, whereas "Ios" was stated as the key factor in picking Swift.

Kotlin and Swift are both open source tools. Swift with 48.4K GitHub stars and 7.76K forks on GitHub appears to be more popular than Kotlin with 28.3K GitHub stars and 3.28K GitHub forks.

Uber Technologies, Slack, and Lyft are some of the popular companies that use Swift, whereas Kotlin is used by Slack, 9GAG, and Rainist. Swift has a broader approval, being mentioned in 993 company stacks & 541 developers stacks; compared to Kotlin, which is listed in 268 company stacks and 208 developer stacks.

What is Kotlin?

Kotlin is a statically typed programming language for the JVM, Android and the browser, 100% interoperable with Java

What is Swift?

Writing code is interactive and fun, the syntax is concise yet expressive, and apps run lightning-fast. Swift is ready for your next iOS and OS X project — or for addition into your current app — because Swift code works side-by-side with Objective-C.

Want advice about which of these to choose?Ask the StackShare community!

Why do developers choose Kotlin?
Why do developers choose Swift?

Sign up to add, upvote and see more prosMake informed product decisions

What are the cons of using Kotlin?
What are the cons of using Swift?
What companies use Kotlin?
What companies use Swift?

Sign up to get full access to all the companiesMake informed product decisions

What tools integrate with Kotlin?
What tools integrate with Swift?

Sign up to get full access to all the tool integrationsMake informed product decisions

What are some alternatives to Kotlin and Swift?
Scala
Scala is an acronym for “Scalable Language”. This means that Scala grows with you. You can play with it by typing one-line expressions and observing the results. But you can also rely on it for large mission critical systems, as many companies, including Twitter, LinkedIn, or Intel do. To some, Scala feels like a scripting language. Its syntax is concise and low ceremony; its types get out of the way because the compiler can infer them.
Java
Java is a programming language and computing platform first released by Sun Microsystems in 1995. There are lots of applications and websites that will not work unless you have Java installed, and more are created every day. Java is fast, secure, and reliable. From laptops to datacenters, game consoles to scientific supercomputers, cell phones to the Internet, Java is everywhere!
Groovy
Groovy builds upon the strengths of Java but has additional power features inspired by languages like Python, Ruby and Smalltalk. It makes modern programming features available to Java developers with almost-zero learning curve.
Python
Python is a general purpose programming language created by Guido Van Rossum. Python is most praised for its elegant syntax and readable code, if you are just beginning your programming career python suits you best.
Go
Go is expressive, concise, clean, and efficient. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel type system enables flexible and modular program construction. Go compiles quickly to machine code yet has the convenience of garbage collection and the power of run-time reflection. It's a fast, statically typed, compiled language that feels like a dynamically typed, interpreted language.
See all alternatives
Decisions about Kotlin and Swift
No stack decisions found
Interest over time
Reviews of Kotlin and Swift
Avatar of Bessalitskykh
Software Development Consultan at MLSDev Inc.
Review ofSwiftSwift

The performance of Swift is almost the same as that of C++, which is considered the fastest in algorithm calculation arithmetics. Apple had this idea in mind and worked to improve the speed of Swift. For example, Swift 2.0 has beaten C++ in several computation algorithms, such as Mandelbrot algorithm. Objective-C is slower because it contains C API legacy.

Swift is faster than Objective-C, because it removed the limitations of C language and has been improved with the help of advanced technologies that were unavailable when C was developed. As mentioned by Apple, Swift was originally designed to operate faster.

Despite the fact that languages are different, they both integrate, and work with Cocoa and Cocoa Touch APIs, for all Apple platforms. Therefore, a regular app-user would not recognize the difference in operating speed between Objective-C vs Swift. Speed also depends on a programmer’s level and capabilities, since a slow app can be written in Swift as well.

Learn more here https://mlsdev.com/blog/51-7-advantages-of-using-swift-over-objective-c

Avatar of Bessalitskykh
Software Development Consultan at MLSDev Inc.
Review ofSwiftSwift

Its performance approaches the one of C++ which is considered the fastest algorithm calculation arithmetics. And Apple strives to improve the speed of Swift. Learn more here https://mlsdev.com/blog/51-7-advantages-of-using-swift-over-objective-c

How developers use Kotlin and Swift
Avatar of Lawrence Cheuk
Lawrence Cheuk uses SwiftSwift

iPhone app, a new born language, it may good but the IDE, xcode is bad compare with Visual Studio. It just like a baby. playground can only use without connect to other library...you can not do a simply refactor of renaming a variable. You can go to definition and find reference, but you can not go to implementation....I should write them on xcode not here basically it is not the fault of swift, but it tightly to it, unless you want to use a notepad to write it.

Avatar of Refractal
Refractal uses SwiftSwift

Most of our newer apps are written completely in swift, with our older ones and some special cases using a mix of Swift and Objective-C, but with Swift 2, the language is pretty much a must-use. "guard" is <3.

Avatar of Philtard
Philtard uses KotlinKotlin

Even though still a young language, it feels so at home sitting in the springboot frame and works with vaadin just great. And in itself it has like all the best parts of java, scala, python mixed into one.

Avatar of Flutter Health Inc.
Flutter Health Inc. uses SwiftSwift

Flutter is coded with Swift v.2.3 and can be run with Xcode v.8.2.1. To launch in Xcode 9.3, the code needs to be migrated to Swift 4.1

Avatar of fileee GmbH
fileee GmbH uses KotlinKotlin

We use Kotlin both in our Android App and increasingly in our polyglot backend services.

Avatar of Maxim Ananov
Maxim Ananov uses SwiftSwift

Most of the app code was gradually rewritten in Swift for better performance and code maintenance.

Avatar of JINJA Ltd.
JINJA Ltd. uses SwiftSwift

Our native iOS app is built on Swift, and most of the basic function is still written in Swift

Avatar of claudiofus
claudiofus uses KotlinKotlin

Statically typed programming language for modern multiplatform applications.

Avatar of Cirrus Labs
Cirrus Labs uses KotlinKotlin

All 20+ micro-services that power Cirrus CI are written in Kotlin.

Avatar of movix
movix uses KotlinKotlin

Unit tests, backend with Spring Boot

How much does Kotlin cost?
How much does Swift cost?
Pricing unavailable
Pricing unavailable