MrSeb writes: "The single greatest problem of touchscreens — except their potential to drive a viral epidemic, of course — is their lack of tactile response. There is a reason that physical, clacky keyboards have been a stalwart of input devices for 150 years, after all. Haptic (literally "touch") feedback has certainly improved in recent years — those gentle, phone-wide vibrations caused by key taps are better than nothing — but what we really need is a level of tactile response that actually feels like you're typing, where instead of your fingers slipping soullessly over the screen, there is friction and the touchscreen actually gives under pressure. Well, guess what: Some Swiss researchers have created exactly that. At EPFL in Lausanne, Neuchâtel, a team of researchers led by Christophe Winter have created a "haptic screen you can really feel" by leveraging piezoelectric materials. By applying voltage to the piezoelectric material it rapidly expands and contracts by a tiny amount — just one micron, 1,000nm — which creates a minute layer of trapped air above the screen. The size and shape of this layer of air can be exactly controlled to create what feels like a textured surface to your hapless finger — and voila, a tactile touchscreen."