Next for iPad and tablets? Touch-back screen technology

Mitch Joel’s post on how touch is changing the game of how we interact with technology has got me thinking about the logical next step for touch interfaces: a surface that responds to our touch in ways we can feel. Somebody is bound to invent a screen that can touch us back. Fingertips’ thousands of nerve receptors make them super sensitive so it would take only a tiny rise on a screen surface for us to feel this digital feedback.

I can imagine many applications of touch-back technology. Here are a few:

• screens could “display” objects with textures;
• the home row of a touchscreen keyboard could be findable via bumps on the F and J keys, and the keys could respond with feedback when pressed;
• spellcheck could be incorporated so keys touched you back a certain way if you misspell a word;
• the text of a web page could be displayed in braille, as could nearly any text: “signs” and geo-coded digital sticky notes in museums, transit stations, and other public places could be broadcast wirelessly and translated into braille;
• fossils, bas reliefs, and topographic maps;
• grid- and guide-lines in visual design applications could be felt, and snap-to-grid could really snap;

Possibilities are endless. When the screen evolves to enable two-way touch interaction will it still be a screen? We may need a new metaphor.