Dash apps require only little boilerplate to get started. They are generated using Python. It binds interactive components like dropdowns, graphs through callbacks from your own Python code. Dash has traditional stateless backend so it is easy to scale apps to serve many users by scaling up the number of worker process. The graph component of Dash is interactive it allows Dash app authors to write applications that respond to hovering, clicking, etc on the graph.
The dashboards are free for Jupyter. You can use any modules or libraries for all Jupyter dashboards. It is easy to make dashboards with Jupyter.