>>> Micro REPL

A MicroPython IDE for Android, Desktop and the Web

Plug a microcontroller in over USB and get a live REPL, a file explorer and a code editor, on your phone, your computer or right in the browser.

Open the web version · Desktop downloads

What it does

Terminal: a live MicroPython prompt. Run code, step through your command history, soft reset the board, or stop a script that's stuck in a loop.

Explorer: browse the board's storage. Create, rename, delete and run files, or import them from your device.

Editor: syntax highlighting, undo and redo, and keyboard shortcuts on desktop. Run a script on the board in one tap, and save it to the board or to any folder on your device.

Recent scripts: files you opened or saved come back in one tap, even after a restart.

Themes: 20+ themes that color the whole app, not just the code.

One app, three platforms: the same app and the same layout on Android, Windows, macOS, Linux and the browser, adapting to phones, tablets and wide desktop windows.

What you need

• A board flashed with MicroPython, and a USB cable
• One of:
  • Android 7.0 or newer, with USB On-The-Go support
  • Desktop: Windows, macOS or Linux
  • Web: a browser with Web Serial, such as Chrome, Edge or Opera on desktop

Tested on

• Boards: Raspberry Pi Pico, Pico W and ESP32
• Platforms: Android, Windows, Linux and Chrome

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Android

   

   

Build

The app comes in two flavors: default has no analytics, and gms adds Firebase Analytics and Crashlytics.

# debug build, installed on a connected device
./gradlew :androidApp:installDefaultDebug

# debug APK
./gradlew :androidApp:assembleDefaultDebug

The APKs land in androidApp/build/outputs/apk/. A release build is signed when local.properties holds the RELEASE_* signing keys.

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Desktop

The desktop app draws its own title bar, follows the theme, and lists every serial port to connect to. Shortcuts in the editor: F5 runs, Ctrl/Cmd + S saves, + O opens and N starts a new script.

Linux: the first time a port can't be opened, the app asks for your permission to install a udev rule that gives every user access to USB serial ports.

Build

# run from source
./gradlew :desktopApp:run

# installer for the current OS: .msi on Windows, .dmg on macOS, .deb on Linux
./gradlew :desktopApp:packageDistributionForCurrentOS

# a single runnable jar for the current OS
./gradlew :desktopApp:packageUberJarForCurrentOS

The packages land in desktopApp/build/compose/binaries/, and the jar in desktopApp/build/compose/jars/. Each installer has to be built on its own OS.

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Web

Open the web version. Connect opens the browser's port picker, which lists only boards and USB-serial chips. Ports you allowed before come back on the next visit.

Web Serial works in Chrome, Edge and Opera on desktop, over HTTPS or localhost.

Build

# development server at http://localhost:8080
./gradlew :webApp:wasmJsBrowserDevelopmentRun

# production build
./gradlew :webApp:wasmJsBrowserDistribution

The production build lands in webApp/build/dist/wasmJs/productionExecutable/, ready to host on any static server.

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Built with

• Kotlin Multiplatform and Compose Multiplatform: one codebase for Android, Desktop and Web
• nemo-editor: the Compose code editor
• usb-serial-for-android: USB serial on Android
• jSerialComm: serial ports on Windows, macOS and Linux
• Web Serial API: serial ports in the browser
• FileKit: file pickers on every platform
• Koin: dependency injection
• Navigation 3: navigation
• Material Symbols: icons

References

• MicroPython REPL
• MicroPython raw REPL
• MicroPython machine module
• Web Serial API

License

Micro REPL is released under the MIT License.