Which solution to build a modern mobile application ?

The contenders

1. Hybrid solutions

Concept: the same development stack as web applications: HTML, CSS, JavaScript.
The application is rendered in the mobile using a "web view" (a web browser embedded in the mobile application)
Usually, the UI is not as smooth as a real native application but animations in the browser have improved a lot recently and it is hard to see the difference.
Plugins (Cordova) are used to communicate with device feature (like the camera, the battery level...)
A building process creates the application for either Android or iOS. Then the application can be uploaded to iTunes or GooglePlay.

Strong points: hybrid applications are easy to test since they can run in the browser (except device specific features, of course).
You can use the same code base to build a web site and a mobile application.

A comparison of mobile frameworks: here

A. ionic

Very popular (+18K Github stars)
Built on top of AngularJS and some Angular tools like angular-ui router

An other solution, based on ionic: [Supersonic] (http://www.appgyver.com/supersonic). No public repository :(

B. reapp.io

Built on top of ReactJS and Webpack (the stack of the moment!)
Not much activity over the last 3 months (only 2.5k stars)

2. [React Native] (https://facebook.github.io/react-native/)

Concept: build an application using only React components
No HTML: only React components that map iOS components.
For example <Text><Text> to create an inline element (the equivalent of a <span> tag in HTML), or <View></View> to create a block element (<div>).
No CSS: JavaScript objects are used to style objects.

Easy to setup on Mac, you can have an application running in 5 minutes.
Only available for iOS (at least now)
16K stars since it was released in March... this is insane!

3. NativeScript

Concept: build an application from JavaScript, XML for views and a subset CSS. Generate real native components, it is does run a simple web view like the hybrid solution.

Not locked to any framework, you can use whatever you want.
Comes with its own double-way binding system to connect views (XML) and data.
3.9K stars, it is slowly becoming popular.
TODO: check by myself!

To sum up

Solution	100% Native	React Native	NativeScript	Hybrid (WebView)
Languages	Swift	React, JS	XML, JS, CSS	HTML5, CSS, JS
Platform	only iOS	only iOS	iOS and Android	iOS and Android

The future: Web workers ?

Use web workers to create rich web applications ? (with offline storage, background processes...)

Note: it seems to be not supported in Firefox 38 ?