> For the complete documentation index, see [llms.txt](https://brlabelectronics.gitbook.io/tutorials-1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://brlabelectronics.gitbook.io/tutorials-1/introduction.md).

# Introduction

After going through this tutorial you will be able to control the four relays that are on the Particle Boron-Argon Relay Shield via the Blynk app on your mobile device or a web dashboard on your computer. To do this you will create a user interface made of of four button widgets that will allow the user to switch on and off the relay coil. Thus giving the user the capability to control physical devices over the internet. Lets get started.

<figure><img src="/files/MmYYFabOBWWiUW7SdJZe" alt=""><figcaption></figcaption></figure>