One Codebase, Every Form Factor
Share application logic and UI across Android, iOS, Windows, Linux, macOS, web, TV, watch, and vehicle targets using Java or Kotlin.
Learn about the ArchitectureWrite Once, Run Anywhere
Build Native Apps Everywhere with Java or Kotlin
One open-source framework for mobile, desktop, web, TV, watch, and in-vehicle apps—with a shared UI and direct access to every native platform.
Open source since 2012 · Commercially supported
Write Once Run Anywhere
Developer-friendly Tooling
Write, debug, and test inside IntelliJ, Eclipse, VS Code, or NetBeans with Maven, an instant simulator, live CSS, inspectors, JUnit, screenshot tests, and on-device debugging.
Learn about the Development EnvironmentPortable UI, Native Reach
Build a consistent, fully themeable UI with CSS and complete drawing control. Mix in native views or call platform SDKs directly whenever you need them.
Why Codename One?
Native, Self-contained Output
Builds with official platform toolchains. Apple, Windows, and Linux targets ship without requiring a JVM on the user's device.
Complete Application APIs
Networking, databases, media, maps, background work, notifications, security, payments, device hardware, and more.
Beyond Phones
Native desktop, PWA, TV, watch, CarPlay, Android Auto, foldables, and first-class keyboard, mouse, and stylus input.
3D, Games, AR, VR, and AI
Portable GPU and game APIs, AR and VR, LLMs, speech, transcription, TensorFlow Lite, and ML Kit integrations.
Fast Development Loop
Instant simulator startup, device skins, code reload, CSS live update, component and network inspectors, and automated tests.
Free and Open Source
The core of Codename One is free and open source (GPL + CE), so it is free to use with commercial projects.
How it works
Codename One combines a portable application runtime and UI toolkit with native compilers, platform ports, build tools, and direct access to native SDKs.
What Codename One is...
A cross-platform runtime and UI library for mobile, desktop, browser, TV, watch, and vehicle applications.
Maven tools that turn JVM bytecode into platform-native projects and executables, locally or through the cloud build service.
Official and community libraries that can bundle portable code, native SDKs, build configuration, and simulator integrations.
Lightweight cross-platform UI components that adapt from touch screens to desktop, TV, watch, and vehicle input.
Drag-and-drop UI builder for rapid visual layout authoring.
Build app-store ready binaries without maintaining local native toolchains.
Run and debug instantly with device skins, inspectors, simulated services, live CSS, and automated tests.
What Codename One is NOT...
Codename One apps compile to native targets, not just wrapped web content.
Unlike toolkits that only bind native components, Codename One provides its own lightweight, cross-platform UI. Application logic and UI can be shared while platform-specific adaptations remain available where they add value.
Yes. You can mix native widgets and lightweight widgets seamlessly.
Yes. Access both system APIs and third-party native frameworks.
Made with Codename One
Arrivu
Voice/AI technology solutions.
BeRider
Shared electric scooters in Prague.
Jubilee Motor
Car insurance app by Jubilee General Insurance.
Ordyx POS
Restaurant point-of-sale and operations platform.
Paltel
Telecom self-service app for customer accounts.
Oxbridge Academy
Student learning and campus engagement app.
HBZ
Community and member services mobile experience.
yHomework
Education app helping students track assignments.
Loved by Developers, Trusted by Enterprises
"Affordable cross-platform toolchain that works!" "Easy extension with third-party libraries, active developer support and attractive pricing..."
Chidiebere Okwudire
SMash ICT Solutions/Senior Engineer at Sioux, Netherlands
"Over 2 million active installations" "[A] mature, solid and reliable platform. It allows you to concentrate [on] developing your app, not platform specific implementations..."
Ram Nathaniel
CEO and Founder of MathUnderground, Israel
"I would advise to all developers to try it out today!" "Easy extension with third-party libraries, active developer support and attractive pricing..."
Lucky Oscar Masango
CTO at BOi Global Group, South Africa
"Going from design to working app is a breeze" "Codename One greatly reduced our development time and costs, while giving us the ability to deliver a custom experience in each platform when needed."
Fabricio Cabeça
Senior Developer at Pmovil, Brazil
"a true write once run anywhere solution!" "Codename One has proven to be a productive tool for us - a true write once run anywhere solution!"
Fabrizio Grassi
Chemetall, Italy
"Simply a great framework!" "[We had] some non conventional requirements and Codename One gave us good answers for all the challenges that we faced during app development."
Hélio Rugani
Sócio Proprietário, Brazil
"Fast and efficient" "Fast and efficient way to eliminate the hassle of targeting multiple platforms without resorting to HTML5!"
Rex Green
Vision24, South Africa
"I utilize my Java knowledge to deliver native apps" "I can deliver native apps for both platforms from a single codebase in half the time, at half the cost, with no need to hire anyone."
Gareth Murfin
Developer, Taiwan
