Flutter programming language which has been developed by Google, and the Russian-produced Kotlin share similarities and differences within the same process of app development. Initially released in 2011, Kotlin is the oldest of the two. Flutter was released in 2017; however, both are considered ‘new’ tools in the tech industry.
JetBrains, a Russian company, developed this programming language. Even though it was released in 2011, Kotlin struggled to gain popularity until 2017—the same year Flutter was released. It’s statistically typed, compatible with Java, and is developed for Android. Additionally, it is a part of Kotlin Multiplatform Mobile, or KMM, which is a framework that utilizes Kotlin on top of Objective-C or Swift.
Unlike Kotlin, Flutter isn’t a programming language. It’s a development kit for user interfacing. It is free and open-source—a big plus—and uses widgets to build apps. Designed to make app development simpler, Flutter can be used in iOS and Android systems while its widget-based process builds on pre-existing codes and elements. Alongside widgets, Flutter uses a programming language called Dart.
The Comparison
Since Kotlin can only be used with Android systems, comparisons will be done with that in mind.
  • Coding Speed
Kotlin’s coding speed has become faster than Java; however, it is Flutter’s hot reload feature that makes it even quicker with coding than Kotlin.
Winner: Flutter
  • Fluidity of Performance
Both Flutter and Kotlin handle coding and performance quickly. The biggest difference between the two here is that Kotlin was built to work solely for Android, whereas Flutter spreads itself thinner in regards to the performance by functioning in iOS and Android systems.
Winner: Kotlin
  • Level of Attention/Preference
The status of Kotlin and Flutter as open-sourced and free means more developers are likely to choose one of the two. Kotlin has increased in popularity within the past year, though Flutter is beginning to close the gap. Flutter’s flexibility is a desirable aspect that gives it an advantage against Kotlin.
Winner: Draw
Pros & Cons
  • Kotlin
The biggest benefits when using Kotlin is its Java compatibility and simplicity. Companies like Pinterest, Coursera, and Trello like this programming language. Unfortunately, it can display inconsistent speeds in code compilation, and only a small community of developers supports it.
  • Flutter
Best used for complex systems due to its speed and flexibility, Flutter is recommended more for small- to medium-sized businesses. Uber, Airbnb, and Alibaba are some of the apps that use Flutter. Cons with Flutter include some instability in its structure and function as well as being a new development tool.
While Flutter and Kotlin share similar advantages, even sometimes small disadvantages, the two can be used for very different projects. Every development tool has certain elements that it’s better at than the others. The largest variance between these refers to how programming languages are used. Since Flutter isn’t a programming language but uses one (Dart), it also has wider parameters for development with its widget element. Kotlin may be more rigid but, similar to a comparison between Java and Python; it’s more of a veteran in the tech industry. Development tools continue to evolve, and there’s no way to tell how long one will remain at the top of the list or when they will become outdated.