Creating interactive apps

In the previous section, we demonstrated the use of R Markdown that is designed for creating dynamic documents. In this section, we will take a quick tour of creating interactive apps where we use a graphical user interface to interact with the data.

Creating a shiny app

R itself is a great environment for data analysis and visualization. However, it is not usual to deliver R and some analytic scripts to the customers to run by themselves. The outcome of data analysis can be presented not only in a HTML page, PDF document, or a Word document, but also in an interactive app that allows readers to interact with the data by modifying some parameters and see what happens with the outcome.

A powerful package, shiny (http://shiny.rstudio.com/), developed by RStudio, is designed exactly for this purpose. A shiny app is different from the interactive graphics we demonstrated previously. It works in a web browser and the developer has all the say about what appears in the...