It is always hard to find out the best web development company in the industry. There are lot of companies that come up with the web development services in cheap rate. But i cant compromise the quality of the work they would perform or how efficent is the web application that suits your requiement.
So whenever opting for a web development company you need to crosscheck their previous works called portfolios. From that you will get clear cut idea how they can build the application.
I would suggest the Dine Media Interactive is reliable Ruby on Rails web development company who can deliver you the best web application in high quality.