1. Development Environment: Create React App provides a pre-configured environment for building React applications, including Webpack, Babel, and ESLint setup, while Nion focuses on simplicity and minimal setup, allowing for more flexibility and customization in the development environment.
2. Routing: Create React App does not come with built-in routing, requiring additional libraries like React Router for implementing client-side routing, whereas Nion includes a simple and lightweight routing system out of the box, simplifying the setup process for routing in the application.
3. State Management: Create React App does not prescribe any specific state management solution, leaving it up to the developer to choose, whereas Nion includes a built-in state management system similar to Redux, reducing the need for additional libraries for managing application state.
4. Component Styling: Create React App does not enforce any specific styling solution, allowing developers to choose between CSS, Sass, or styled-components, while Nion promotes the use of CSS-in-JS libraries like Emotion for styling components, offering a more cohesive approach to styling within the application.
5. API Integration: Create React App does not include any specific tools for API integration, requiring developers to implement their preferred solution, whereas Nion includes tools like Axios or Fetch for seamless API communication, providing a smoother experience when working with external data sources.
6. Code Splitting: Create React App supports code splitting out of the box, allowing for better performance by loading only necessary code chunks, while Nion includes a similar code splitting mechanism, ensuring optimized loading times for larger applications.

In Summary, Create React App provides a more structured and opinionated setup for React applications, while Nion offers a simpler and more flexible approach with built-in solutions for common development tasks.