Android API reference

Start building your Android app with the Android Platform APIs. They are available in Kotlin and Java.

Note: Many Kotlin reference topics are derived from Java-based source code. This means that some Kotlin reference topics might contain Java code snippets.

These additional libraries make it easy to add additional functionality and features to your app.

Jetpack

AndroidX

Refactored versions of the Android APIs that are not bundled with the operating system.
Reference  User Guide

Jetpack Compose

Jetpack Compose is a modern toolkit for building native Android UI. Jetpack Compose simplifies and accelerates UI development on Android with less code, powerful tools, and intuitive Kotlin APIs.
Reference  User Guide

AndroidX Test

Includes APIs for testing your Android app, including Espresso, JUnit Runner, JUnit4 rules, and UI Automator.
Reference  User Guide

AndroidX Constraint Layout

Includes ConstraintLayout and related APIs for building constraint-based layouts.
Reference  User Guide

Databinding Library

Includes APIs to help you write declarative layouts and minimize the glue code necessary to bind your application logic and layouts.
Reference  User Guide

Device Libraries

Android Automotive Library

Provides APIs for building Android Automotive apps.
Reference  User Guide

Android for Cars App Library (Beta)

A library for building Android Auto apps. This library is currently in beta. You can design, develop, and test navigation, parking, and charging apps for Android Auto, but you can't distribute these apps through the Google Play Store yet. We will make announcements in the future when you can distribute these apps through the Google Play Store.
Reference  User Guide

Android Things Library

Provides APIs to build connected devices running the Android Things platform.
Reference  User Guide

Android Wearable Library

Provides APIs to build apps for wearable devices running Wear OS by Google.
Reference  User Guide

Other Libraries

Material Components

Material Components for Android (MDC-Android) help developers execute Material Design to build beautiful and functional Android apps.
Reference  User Guide

Android NDK

The Android NDK is a toolset that lets you implement parts of your app in native code, using languages such as C and C++.
Reference  User Guide

Google Play

Play In-app Billing Library

Provides APIs to help you implement Google Play's in-app billing and subscription features.
Reference  User Guide

Play Core Library

Provides APIs to help you request, monitor, and manage on demand downloads for Play Feature Delivery, Play Asset Delivery, and offers additional APIs such as in-app updates and in-app reviews. This library is available in Java, Native code, and Unity.

Play Install Referrer library

Provides APIs to securely retrieve referral content from Google Play.
Reference

Deprecated Libraries

These libraries are superseded by the AndroidX libraries and are no longer maintened. They are still shipped in the SDK to support legacy apps. For more information see the androidx migration guide.

Android Support Library

Provided a variety of Android feature and utility APIs that are compatible with a wide range of platform versions. The original library is superseded by the AndroidX libraries.

Android Test Support Library

Includes APIs for testing your Android app, including Espresso, JUnit Runner, JUnit4 rules, and UI Automator. The original library is superseded by the AndroidX Test library.

Architecture Components

Includes APIs for a variety of core app components, such as APIs that manage your UI component lifecycle, data persistence, view model, and more. The original library is superseded by the AndroidX libraries.

Constraint Layout Library

Legacy Support Library ConstraintLayout and related APIs for building constraint-based layouts. The original library is superseded by the AndroidX constraintlayout library.