Introduction to Shiny

Introduction to Shiny: Build Interactive Web Apps with R

What is R Shiny?

Shiny is an R package that allows you to build interactive web applications without needing to learn HTML, CSS, or JavaScript. Whether you’re a data scientist, researcher, or business analyst, Shiny helps transform static reports into dynamic, web-based applications.

With just a few lines of R code, you can create dashboards, visualize live data, and interact with datasets in real time.

Why Use Shiny?

Here’s why Shiny is a game-changer for R programmers:
✅ Easy to Get Started – No need for web development skills, if you know coding in R that is enough to get started in Shiny.
✅ Interactivity – Users can manipulate data and see updates instantly
✅ Data Visualization – Generate interactive plots and tables effortlessly
✅ Deploy Anywhere – Publish apps online with platforms like ShinyApps.io which is easy to share with others.

Shiny App Structure

Shiny apps are structured in three main ways:
1️⃣ Single File (app.R) – Everything (UI + server) is written in a single file.
2️⃣ Separate Files (ui.R & server.R) – UI and backend logic are split into different files.
3️⃣ Shiny Frameworks (Golem, Rhino) – For advanced Shiny applications with modular structures.

Reactivity: The Power of Shiny

Shiny’s reactivity makes apps dynamic. It works by updating outputs whenever inputs change.

Reactivity in Shiny can be seen in different forms :
🔹 Reactive Inputs – User-provided values (e.g., text boxes, dropdowns)
🔹 Reactive Expressions – Automatically recalculates when inputs change
🔹 Reactive Outputs – Dynamically updates tables, plots, and text based on inputs
🔹 Observers – Executes actions (e.g., saving a file) without returning a value

Shiny in Action

Here are some real-world Shiny apps:
🔹 Basic Apps – Example 1
🔹 Advanced Dashboards – COVID-19 Dashboard
🔹 Creative Uses – TidyTuesday App

Deploying Your Shiny App

Once your app is ready, you can publish it on:
📌 ShinyApps.io – A free hosting platform (up to 5 apps, 25 active hours)
📌 RStudio Connect – Enterprise-level hosting for Shiny apps

Further Learning

Want to dive deeper into Shiny? Check out these resources:
📖 Shiny Official Docs
📖 Mastering Shiny
📖 Shiny Gallery

Conclusion

Shiny is a powerful tool for turning R scripts into interactive web applications. Whether you’re analyzing data, building dashboards, or sharing insights, Shiny makes it simple and accessible.

This post is inspired by Pune R UseR Group (Pune RUG) talk on Introduction to Shiny and the resources used for the talk can be accessed on Github.

Are you ready to build your first Shiny app? Let’s get started! 🚀