Google has figured out how to replace the command input tools for controlling various gadgets on the human body. We are talking about the technology of "smart tattoos", which are now a kind of wearable electronics.
The working name of the novelty is "SkinMarks", researchers from the University of Saar (Germany) took part in its creation. They have developed a special type of ink that reacts to its own deformation. For example, if you draw a line on your finger, and then bend it, stretching the skin will carry away the paint particles with it - the line will not break, but will become thinner. On the hands of a person alone, there are dozens of places where you can fix the deformation of the tattoo lines, which turns them into a universal tool for issuing commands.
But what will motivate users to paint themselves with such tattoos? Google says that finger and hand gestures are easier, more natural and more familiar than all other ways of giving commands. And there is no problem to make personal settings - to teach the system to perceive different gestures as the user wishes. You will try and you will like it, plus the tattoo is always with you and does not need to be recharged.