Dash (Plotly)
What it is: Python framework for building analytical web applications. More powerful than Streamlit, production-ready.
What It Does Best
Production apps. Built for real applications, not just demos. Handles authentication, caching, deployment.
Full control. More complex than Streamlit but more customizable. Build exactly what you need.
Plotly integration. Native Plotly charts. Beautiful, interactive visualizations built-in.
Pricing
Open source: Free
Dash Enterprise: $950+/month (deployment, auth, advanced features)
When to Use It
✅ Production analytical applications
✅ Need custom layouts and interactions
✅ Willing to write more code for flexibility
✅ Real users, not just demos
When NOT to Use It
❌ Quick prototypes (Streamlit faster)
❌ Non-analytical web apps (use Django/Flask)
❌ Need simplest possible tool
Bottom line: Streamlit for demos, Dash for production. More complex but scales better. Choose this when the app matters to your business.