Next.js is a React framework used to build websites, SaaS applications, ecommerce stores, dashboards, and custom web applications.

Next.js provides flexible rendering options, routing, performance features, and a strong React development ecosystem, making it suitable for both content-driven websites and complex applications.

Yes. Next.js can be used to build custom ecommerce storefronts and can connect with platforms such as Shopify, Medusa.js, and other API-based commerce systems.

Yes. Next.js can connect with headless CMS platforms such as Sanity, Strapi, Directus, Storyblok, and Contentful through APIs.

The cost depends on the project's scope, number of pages, application complexity, integrations, design requirements, and ongoing support. A simple website will cost significantly less than a custom SaaS or ecommerce application.