Anyone who knows me should already be familiar with how I feel about touch screens, especially in regards to typing.
Well, Michael Miller has shared an article explaining it far better than I ever have, written by Bret Victor, a professional interface designer.
Here's Michael's post discussing Bret's rant:
Anyone who has tried to type on a touch screen "keyboard" knows this is true.
Touch devices are wonderful but they are only part way there, the device certainly "feels" your touch but what do you feel in return? A sheet of glass. Featureless, numb.
You can't use this device without looking at it carefully to make sure that your fingers are keeping up with the visual metaphor being presented. Eyes and hand must work together carefully and while touch might be less mediated and indirect than, say, using a mouse, it still requires far more cognitive and sensual effort than using a physical device. A physical keyboard for example can be used, in fact it requires that it be used, without you looking at what your fingers are doing.
"Are we really going to accept an Interface Of The Future that is less expressive than a sandwich?"
Touch interfaces are not the destination but a way-station. In the future touch devices will become tactile devices.
Article: A Brief Rant on the Future of Interaction Design