How does Software as a Service (SaaS) work with open-source model?
The Open-source license does not prevent you from charging for use of the software service. Many Software-as-a-Service sites rely on open-source software. The majority of your users would still prefer to use a maintained hosted version of the software regardless of availability of source code. The existence of an open-source project can also often help to promote your service. For a successful story of this model, refer to WordPress.com.