Kotlin is an open source language with its own documentation and community, so we don't provide documentation about the actual language here. If you're new to Kotlin, we recommend you check out the following resources.
When you're ready to use Kotlin, see Get Started with Kotlin on Android.
- Kotlinlang.org: The official Kotlin website. Includes everything from a guide to basic syntax to the Kotlin standard library reference.
- Kotlin Koans Online: A collection of exercises in an online IDE to help you learn the Kotlin syntax.
- YouTube: This search for "Kotlin on Android" provides a variety of high quality technical talks.
- O'Reilly course: An 8-hour Kotlin course, "Introduction to Kotlin Programming," by Hadi Hariri, a developer at JetBrains. Requires subscription; 10-day free trial available.
- Treehouse course: "Kotlin for Java Developers" teaches Kotlin with an emphasis on Android. Requires subscription; 7-day free trial available.
- Udemy course: "Kotlin for Beginners" teaches Kotlin from scratch. Requires subscription; new student discount available.
- Kotlin in Action: By Dmitry Jemerov and Svetlana Isakova, Kotlin developers at JetBrains.
- Kotlin for Android Developers: By Antonio Leiva. One of the first books about Kotlin.