Kotlin 2.4 and Android Studio Quail 1 land 48 hours apart

JetBrains shipped Kotlin 2.4.0 on June 3, 2026, one day after Google's Android Studio Quail 1 went stable on June 2. The two are coupled by design: the latest Kotlin is bundled into the latest IntelliJ IDEA and Android Studio, so a new stable Studio and a new stable Kotlin landing in the same week is the JetBrains-platform release cadence rather than a coincidence.

Kotlin 2.4 is the larger half. Context parameters and explicit backing fields both reach stable, the release adds several annotation use-site target features, and the common standard library stabilizes the UUID API. On the JVM, Java 26 becomes a supported bytecode target and annotations in metadata are on by default. Kotlin/Native adds support for Swift packages as dependencies, updates Swift export, and enables the CMS garbage collector by default; Kotlin/Wasm turns on incremental compilation by default and adds WebAssembly Component Model support; Kotlin/JS picks up value-class export and ES2015 inlining. On the build side, 2.4 is compatible with Gradle 9.5.0, and the immediate predecessor on the language side was 2.3.20.

Android Studio Quail 1 is the smaller but more structural half: the first release of the new Quail codename line — the Q animal cycle after Panda — versioned 2026.1.1 under the IntelliJ-aligned YYYY.N.P scheme, raising the floor to AGP 9.2 and Gradle 9.4.1. Read the two as one release event: the Android toolchain's stable floor moves up across language, IDE, and build tooling in the same week. For a working Android or Kotlin-multiplatform team that means a coordinated bump — new compiler, new IDE, new Gradle and AGP minimums — rather than a string of independent upgrades, which is the practical reason JetBrains and Google sequence these within a 48-hour window.