Breaking Dev: Taxonomy of Touch

by Luke Wroblewski April 22, 2011

At the Breaking Development Conference in Dallas TX, Nate Koechley discussed elements of touch primitives, gestures and semantics in his presentation “Taxonomy of Touch”. Here’s my notes from his talk:

Touch Input

  • Input can have different modes (mechanical, audio, or visual). It can be discrete vs. continuous. Different input factors have different degrees of freedom.
  • Touch is direct, discrete & continuous, absolute, and has a high degree of freedom.
  • The big mobile players: iOS, webOS, Blackberry, Android, and Windows Phone 7 all support touch as input. But desktop touch interfaces are proliferating too.
  • The Web Events working group is working to develop touch standards that enable developers to build applications that better fit touch-based devices. They are working on a spec for low-level physical events & high-level representational events.
  • Fit the user ”Implementation model to mental model”. Now, fit the device!

Touch Intent

  • I want to see more: use expand gesture
  • Intentional, representational, gestural, physical
  • Physical: Lowest level, physical gestures. “when the user moves two touches toward each other”
  • Gestural: middle layer, describes a specific mapping (often device specific) “in a pinching gesture”
  • Representational: highest level of abstraction (means to an end) “the conventional meaning is zoom-out.”
  • Intention: above the APIs, what’s the user’s goal? “user wants to see more of an object being manipulated”

Implement Touch

  • DOM doesn’t include all the interesting moments we care about. One way to do that is to create custom events. Custom events: interesting moments in your application not just the browser
  • Synthetic events: can add things to nodes/page
  • It may be a best practice to move up a layer from difference between mouse & touch. Same as what was done for keyboard & mouse
  • YUI normalizes touch events to works across capable browsers.

Invent Touch

  • Adapt the technology to the user not the user to the technology
  • There’s an opportunity to push gestures forward.
  • Windows phone 7 goes up to 10 touch points, 3M has 50 touch points.