R & its best IDE (according to the majority of R daily users) offer as a wondeful framework for web apps creation. It's called Shiny. The success of this web apps framework generates the development of a large package's ecosystem arround shiny. From prototyping, realising beautiful UI, to testing and deploying to the production scale. With Shiny it's possible to realise both the front and the back end parts inside R :-) Isn't huge !
We are going to start with a simple shiny app, discover the variety of possibilities offered to us when prototyping UI, before to pass to the server side & the other packages of the ecosystem :-)