Onsen UI

Onsen UI is an open source framework for building hybrid mobile interfaces that look native. If you develop with HTML, CSS and JavaScript and want an app with the look of iOS or Android, Onsen UI provides the components to do it without learning Swift or Kotlin.

Onsen UI is a UI component framework for hybrid mobile app development, maintained by Monaca and open to the community as an open source project. It provides a library of ready-made components — buttons, inputs, cards, toolbars, tab bars, bottom sheets, dialogs, action sheets, side menus, lists and much more — that mimic iOS and Material Design (Android) conventions, automatically adapting to the platform the app runs on. It integrates with major JavaScript frameworks: React, Vue, Angular and vanilla JavaScript are all supported, making it flexible for teams with different stacks. Apps built with Onsen UI are packaged with Cordova or Capacitor for distribution on the App Store and Google Play. Its strength is the mix between HTML/CSS/JavaScript familiarity and a visual result that approaches native apps without needing to learn mobile-specific languages. It's open source under the Apache 2.0 license.

For web developers experienced in HTML, CSS and JavaScript who want to create hybrid mobile applications with a native look without learning native mobile development languages.

Onsen UI is completely free and open source under the Apache 2.0 license. There are no premium versions or paid plans for the framework itself. Monaca, the company that maintains it, separately offers a paid cloud service for app compilation and distribution, but using the framework itself is free.