Overview:
In order not to waste time on installation in the workshop, it is better to get all the installations done beforehand. It’s not a lot, I estimate that all installations will take you less than an hour.
 

This will include:

• Part 1 - Install Arduino-IDE (Desktop-App).

• Part 2 - Install the Feather 32u4 Bluefruit-LE Board, using the Arduino Board Manager.

• Part 3 - Install the Blufruit-LE Arduino Library by Adafruit.

• Part 4 - Install the Bluefruit-LE Mobile App (on your mobile phone).

• Troubleshooting