This is proof of concept by a girl who spent $26 dollars on materials. I'm sure there are practical applications if we think hard enough and if we threw some money at it. The circuit is probably an invention. I hope she has something on file at the USPTO.

By the way, I would like to know who saw the video when they post. The girl explains a typical journey of an inventor. She also mentions the weaknesses that some have repeated here. Her story is inspiring. It's worth a watch. I hope to raise my daughter to have her type of confidence.