For quite some time, people have been asking for a haptic keyboard on the iPhone -- a way to produce tactile feedback when a user taps or hovers over a key. If you've used the Wii, you'll know exactly what I'm talking about. It's that sensory feedback that confirms you've selected a wiibutton. This morning TUAW reader zebrum sent in a tip that a couple of University of Glasgow students (Malcolm Hall and Eve Hoggan) had built a prototype.
I gave it a try and while I applaud the students for their effort, it's not exactly ready for prime time. It's a proof of concept, not a general-use mod. You test it out in a simple text editor. You can't for example, enable this for Safari. Moreover, it's pretty darned unstable. Sometimes it crashes. Sometimes the vibration keeps going until you quit the program, re-launch and get it to stop by tapping a key.
What's cool about this app? It shows a neat new way of thinking about iPhone interaction -- even if that way is going to pay havoc on batteries if actually implemented -- and to use a helpful technology that's available on other devices. This kind of feedback uniquely highlights where keys start and end. Run your finger along the keyboard and receive instant tactile feedback (obviously in addition to the letter popups) when your selection changes.