Looks to be a similar device to the Myo Armband: https://www.myo.com/
https://www.scientificamerican.com/article/forearm-gestures-...
> Previously, researchers have been able to detect up to 25 individual motor units. Reardon claims to have greatly surpassed that, recording about 100 individual units
So basically, they have achieved much greater throughput, and that number is going up.
I had hoped to use it to switch work spaces or bring up frequent apps, but it was easier to do things manually rather than have the gesture fail 50% of the time.