Native mobile apps in JavaScript. Simple.

TypeScript is a first class citizen for app development with Tabris.js 

Develop secure, enterprise-class mobile applications

Create native UIs from a single code base in JavaScript or TypeScript.
The Tabris.js framework is an execution engine with a thin layer calling native widgets.

No special setup necessary (you can build for iOS without a Mac!) and no compiling.
You can execute your changes instantly on your mobile device.