A web app is an application that runs on your browser. A good example is Gmail. Unlike a website, a web app is about user interaction; as a matter of fact, most popular products today are built as web applications. Software-as-a-Service (SaaS) is a business model most often used in enterprise space, although there are numerous consumer products operating as SaaS – for example, the highly successful “Dropbox”.

SaaS is practically a subscription business model, where users pay recurring fees for the ability to use your product. It can be a highly profitable, predictable and secure business model… If executed the right way.