Answer:
This requires a percentage of people with zero UI device, and how many of them are comfortable with it. The rest can be calculated. However, since it is not given, as an assumption, one should note that more and more people are going to have it, but in the beginning, only a few out of them will be comfortable with it at the start, as it is a new technology.
Explanation:
It's important to understand what is a Zero UI device. This means a touchless UI experience. The era of the touchscreen is going to vanish soon hence, and computers will be able to understand our feelings and gestures. Our gestures will drive the computers now, and that is going to be a new style of UI in the computer world. The era has not yet arrived, but you might soon find that era starting, and at the beginning, people will find it hard though with time they will start feeling comfortable with it.
