Java on Mobile

Bringing real Java to mobile.

Java runs everywhere — server, cloud, and desktop — but running it seamlessly on mobile remains challenging. This project aims to fix that by creating the code, tools, and documentation to make Java a first-class citizen on iOS and Android.

A key part of this effort is the OpenJDK/mobile project — an official downstream repository of OpenJDK/jdk containing the minimal patches required for JVM and library support on mobile devices. Our long-term goal is to upstream these patches into OpenJDK/jdk, eliminating the need for a separate repository.

We focus on two main use cases:

• Java libraries on mobile – Allow developers to take existing Java libraries and convert them into fully supported components on mobile platforms.
• Java applications on mobile – Enable developers to write full mobile applications in Java, including JavaFX-based apps.

⚠️ Note: This is not (yet) a tutorial for building mobile apps in Java. The goal is rather to build the infrastructure that makes it possible. We try to document all required steps in detail, and we hope that more contributors will join this project.

From here, you can explore:

• Mission – Our philosophy, constraints, and guiding principles.
• Platforms – How we plan to bring Java to iOS and Android.
• Roadmap – Next steps and current issues.
• OpenJDK Mobile – Relationship with the official OpenJDK/mobile project.