A simple NDA and signature pad app for Heroku:
http://cl.ly/image/3W3X1U2l390p
To run this app locally you need Ruby 1.9.3 and Postgres.
$ bundle install
$ cp config/database.example.yml config/database.yml
$ bundle exec rake db:create
$ bundle exec rake db:migrate
$ foreman start
$ heroku create
$ git push heroku master
$ heroku run rake db:migrate