Kotlin is probably the biggest change to come to Android development in the last few years, since the change from Eclipse to Android Studio anyway. Kotlin was announced by JetBrains in July 2011 and released as open source in February 2012. Version 1.0 was released in February 2016, with Google announcing first-class support for the language at Google I/O 2017. Android Studio 3.0 came with full support for Kotlin already included (and is the minimum requirement for the following recipes.)
Why Kotlin?
With so many existing languages already available, why did JetBrains create another? According to their own announcements, they were looking for an alternative to Java. Since over 70% of their existing code was already in Java, starting from scratch wasn't an option. They wanted a modern language that was compatible with Java. After comparing the many options...
