Kotlin became the preferred Android development language, replacing Java as Google’s recommended starting point for new Android apps.
Google announced its Kotlin-first Android strategy at Google I/O 2019. Kotlin is concise, interoperable with Java, and includes features such as null-safety that can reduce common programming errors. Android Studio provides first-class Kotlin support, and modern tools such as Jetpack Compose are designed around it.
Kotlin did not literally eliminate Java from Android. Existing Java applications remain supported, Android APIs continue to work with Java, and Kotlin can call Java code directly. Many production apps also combine both languages during gradual migration.
Kotlin was created by JetBrains and first released publicly in 2011. Its rise on Android followed Google’s official support announcement in 2017, making it the modern successor to Java’s dominant role in Android app development.