React.js, a popular front-end framework, requires additional features for building production-level applications, which it doesn't offer out-of-the-box, such as routing and code-splitting. Next.js complements React by providing these production-ready features, making it easier for developers to create robust applications. The tutorial outlines the process of automating the deployment of a Next.js application to Heroku using CircleCI, involving setting up a Next.js project, configuring a Heroku application, and establishing a CircleCI pipeline. Key steps include creating environment variables for authenticated access, writing a Procfile for Heroku deployment, and utilizing CircleCI's Heroku orb to streamline the deployment process. The guide emphasizes the efficiency of automating deployments to avoid the pitfalls of manual processes, ensuring seamless updates to applications.