Mastering Shiny: Build Interactive Apps, Reports, and Dashboards Powered by R 319

 If you’ve never used Shiny before, welcome! Shiny is an R package that allows you to easily create rich, interactive web apps. Shiny allows you to take your work in R and expose it via a web browser so that anyone can use it. Shiny makes you look awesome by making it easy to produce polished web apps with a minimum amount of pain.

In the past, creating web apps was hard for most R users because:

You need a deep knowledge of web technologies like HTML, CSS, and JavaScript.

Making complex interactive apps requires careful analysis of interaction flows to make sure that when an input changes, only the related outputs are updated.

Shiny makes it significantly easier for the R programmer to create web apps by:

Providing a carefully curated set of user interface (UI for short) functions that generate the HTML, CSS, and JavaScript needed for common tasks. This means that you don’t need to know the details of HTML/CSS/JavaScript until you want to go beyond the basics that Shiny provides for you.

Introducing a new style of programming called reactive programming, which automatically tracks the dependencies of pieces of code. This means that whenever an input changes, Shiny can automatically figure out how to do the smallest amount of work to update all the related outputs.

 People use Shiny to:

Create dashboards that track important high-level performance indicators while facilitating drill-down into metrics that need more investigation.

Replace hundreds of pages of PDFs with interactive apps that allow the user to jump to the exact slice of the results that they care about.

Communicate complex models to a nontechnical audience with informative visualizations and interactive sensitivity analysis.

Provide self-service data analysis for common workflows, replacing email requests with a Shiny app that allows people to upload their own data and perform standard analyses. You can make sophisticated R analyses available to users with no programming skills.

Create interactive demos for teaching statistics and data science concepts that allow learners to tweak inputs and observe the downstream effects of those changes in an analysis.

In short, Shiny gives you the ability to pass on some of your R superpowers to anyone who can use the web.

 Who Should Read This Book?

This book is aimed at two main audiences. R users who are interested in learning about Shiny in order to turn their analyses into interactive web apps. To get the most out of this book, you should be comfortable using R to do data analysis and should have written at least a few functions.

Existing Shiny users who want to improve their knowledge of the theory underlying Shiny in order to write higher-quality apps faster and more easily. You should find this book particularly helpful if your apps are starting to get bigger and you’re starting to have problems managing the complexity.