Look All the photos and videos in this link:
Taekwondo training (theWorld Champion)
Personal trainer and cell phone
Fitness Sport Training
There are 4 (or more), lights, one of them is the "server"
The server holds 2 nodeMCU boards one is the server itself (the WiFi hotspot) and the other one is the sensor light, all other lights holds only 1 nodeMCU board each.
They are interconnected without wires via WiFi.
The user connects with the cell phone to this same server via WiFi.
Configure the system with parameters such as ignition time, delay, range of activation distances, and type of sequence (sequential or random).
All settings are available in a very simple screen shown in the cell phone.
No need to install software on the phone, just access a link in the browser to see the screen.
Connect the cell phone to the server via WiFi, browse to http://192.168.4.1 use TrainerLights named WiFi spot and password 1234567890