Two principles
- A resistive screen has two layers that touch when pressed. It works with gloves and a stylus, but it is less precise. It was used in older PDAs and satnavs.
- A capacitive screen measures the change in the electric field when a finger touches it. It can handle several touches at once and gestures, which is why it is in every smartphone.
Why it does not work with gloves
A capacitive screen needs a conductive finger. Winter gloves with touchscreen fingertips have metal threads woven into the fingers.
The future
Screens are flexible (foldable phones), have a fingerprint sensor right under the glass and can even detect how hard you press.