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Pros
Pro Is built to solve industrial problems
Kotlin has been designed and built by developers who have an industrial background and not an academic one. As such, it tries to solve issues mostly found in industrial settings. For example, the Kotlin type system helps developers avoid null pointer exceptions. Reasearch languages usually do not have null at all, but APIs and large codebases usually need null.
Pro Officially supported for Android development
Starting with version 3.0 of Android Studio, Kotlin support will be built-in. This means that it's now easier than ever to use Kotlin for existing Android projects or even start writing Android apps only with Kotlin from scratch.
This also means that Kotlin and Kotlin plugins for Android Studio will be fully supported in the future and their likelihood of being abandoned is quite small since Google is fully embracing the language for their Android ecosystem (alongside Java and C++).
Pro Easy adoption for existing Java programmers
Kotlin runs on the JVM and Java interoperability has been one of the main objectives since the language was born. It runs everywhere Java does; web servers, mobile devices (Android), and desktop applications. It also works with all the major tools in the Java ecosystem like Eclipse, IntelliJ, Maven, Ant, Gradle, Spring Boot, etc.
All of this makes adoption extremely easy even for existing Java projects. On top of this there's also ensured Type safety and less boilerplate code needed.
Cons
Con May be hard for programmers already used to imperative style to learn functional programming from Kotlin
Since Kotlin does not enforce any particular paradigms and is not purely functional, it can be pretty easy to fall back to imperative programming habits if a programmer comes from an imperative background.