Ninja UI is described as 'Ninja User Interface, the jQuery plugin for lethal interaction' and is an website in the Development category. There are more than 10 alternatives to Ninja UI, not only websites but also apps for a variety of platforms, including Mac, Windows, Linux and jQuery. The best alternative is React, which is both free and Open Source. Other great sites and apps similar to Ninja UI are UIkit (Free, Open Source), Semantic UI (Free, Open Source), Purecss (Free, Open Source) and jQuery UI (Free, Open Source).
Kube is one of the world's most advanced and flexible frameworks. Kube helps you spend less time on routine tasks and more time creating amazing products. Focus on success, and Kube will cover the technology behind it.
A very easy to use, cross platform, jQuery based UI toolkit, that's still small in size, has the features you need, and doesn't get in your way of doing things ! jKit is framework js for easiest developpement like twitter bootstrap.