What are some alternatives?
When comparing React and ember.js, you can also consider the following products
Okta - Enterprise-grade identity management for all your apps, users & devices
AngularJS - AngularJS lets you extend HTML vocabulary for your application. The resulting environment is extraordinarily expressive, readable, and quick to develop.
Auth0 - Auth0 is a program for people to get authentication and authorization services for their own business use.
Backbone.js - Give your JS App some Backbone with Models, Views, Collections, and Events
OneLogin - On-demand SSO, directory integration, user provisioning and more
ExpressJS - Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple