As someone in this thread said, with this device we should tap to our arms 1000+ times per day.
I think that this is horrible! Just think of it! Every tap includes a few newtons of force. With every tap this force summs up and could cause hematomas on our arm or just ruin it. It's like when water flows on rocks and ruins them.
I wouldn't like to have such a device attached to my arm.
Today, cellular phones, tomorrow, phones on your hands, next week, phones in your BRAINS