Choosing between a website and a web app

A marketing website explains and persuades. A web application lets a user complete ongoing tasks. Many early-stage ideas need both eventually, but very few need every feature on day one.

If your main goal is validating demand, begin with the smallest experience that can communicate the offer and capture intent. If users must create data, collaborate or manage a workflow, an application layer becomes necessary.

The right first version is not defined by how little it costs. It is defined by how quickly it can answer the most important business question.