Surprisingly well!

It's a really well put together demo & tutorial.

I held a pen up next to me and held the green button.

Then did the same with a mouse.

It would flick between the two if I was holding nothing, so I held the orange button for a bit while holding nothing.

Worked pretty much every time.

Training is fast enough with a few hundred images per class that I didn't notice any delay.

It's working great because they're using a state of the art model (SqueezeNet https://github.com/DeepScale/SqueezeNet) and also the samples / experiments you do are often only on yourself, in the same lighting, same clothes, etc. So it gives a nice idealized playground environment that mostly eliminates annoying details like this.

there are 3 default classes, so you train according to each class(e.g. hand waving, sitting still, etc) you take examples of each(using your camera). you map the input data from your camera to some output data(e.g. if i used the green button to take photos of me waving), display a GIF of a cat that's waving. instead of a GIF you can use sound too