Sortable For Rails
Sortable is an awesome JS library to create drag and drop interfaces on most browsers and touch devices.
The sortable_rails gem integrates Sortable into the Rails asset pipeline.
Usage
Install sortable_rails gem
Include sortable_rails in Gemfile
 gem 'sortable_rails', '~> 1.0.0'
Then run bundle install
Note: sortable-rails is a different gem
Include javascript
Add to your application.js
 //= require sortable