Platform as a Service is mostly free for the small scale App, CMS Hosting. New users must be careful about Cloud Computing Disaster Recovery as users of PaaS. We published about Cloud Computing Disaster Recovery due to Increased demand, as somewhat false promise of Platform as a Service is productivity. Platform as a Service providers like Heroku claim to increase productivity by abstracting the user from the details of the underlying infrastructure and they go further up and claim that the Platform as a Service makes the cash redundant applications. You might know about the historical service interruption aka full shut down encountered in summer this year by Heroku, because of Amazon, which is their rented Infrastructure.
Please read more- Platform as a Service : Careful About Disaster Recovery as User