The difference in plain terms
A website is content: pages, images, forms. Visitors read and contact you. A web app is software: users log in, create and change data, and the app responds to them individually. A booking system, a customer portal, an internal dashboard and an online store with accounts are all web apps, even if they look like websites.
Which one you need
- Need to explain, market and capture leads: website.
- Need users to log in and do things: web app.
- Need to replace a spreadsheet, a paper process, or a manual email workflow: web app.
- Need to sell products with accounts, orders and history: web app (an online store).
When you need both
Most businesses do. The public website markets the product; the web app is the product. They can share a design, but they are built differently: the website on a content system like WordPress, the web app on an application framework with a database, authentication and an API.
Cost and timeline
A business website typically costs $4,000 to $15,000 and takes four to eight weeks. A web app starts around $15,000 for a simple tool and runs to six figures for a full product, over six weeks to six months. Treating a web app like a website in the budget is the most common expensive mistake.