flet-dev/flet

Flet is a framework that lets you build apps for mobile (iOS and Android), desktop (Windows, macOS, Linux), and web, all from a single Python codebase. The key selling point is that you never need to write HTML, JavaScript, Dart, Swift, or any other language typically required for building apps on these platforms. Everything is written in Python. Under the hood, Flet uses Flutter (Google's UI toolkit) to render the interface, which means the apps look polished and professional on every platform. The framework ships with over 150 built-in interface components, things like buttons, text fields, navigation bars, charts, and dialogs, and also supports popular Python libraries like numpy, pandas, opencv, and pillow on mobile devices. A simple counter app example from the README shows how a working multi-platform app with buttons and a text field can be built in about 20 lines of Python. You run the app with a single command, and adding the --web flag immediately serves it as a web app instead. Flet is aimed at Python developers, including beginners and data scientists, who want to ship real apps across all major platforms without learning frontend development. You can also package apps for distribution on the App Store and Google Play. It requires Python 3.10 or newer.