ember.js is described as 'You can write less code with Ember's Handlebars integrated templates that update automatically when the underlying data changes' and is an app in the Development category. There are more than 50 alternatives to ember.js for a variety of platforms, including Windows, Linux, Mac, Online / Web-based and Self-Hosted solutions. The best alternative is Vue.js, which is both free and Open Source. Other great apps like ember.js are React (Free, Open Source), AngularJS (Free, Open Source), ExpressJS (Free, Open Source) and Svelte (Free, Open Source).
Polymer is a library that uses the latest web technologies to let you create custom HTML elements. Build anything from a button to a complete application as an encapsulated, reusable element that works across desktop and mobile.
Riot lets you build user interfaces with custom tags using simple and enjoyable syntax. It uses a virtual DOM similar to React but faster. Riot is very tiny compared to industry standards. We think there is a clear need for another UI library.