Author: Jochen Wolters

The Bubble Cursor in Action

Anand Kulkarni has developed an interesting and fun demo of the bubble cursor, a UI concept conceived by Tovi Grossman and Ravin Balakrishnan.

Standard mouse pointers usually have just a single-pixel “hot spot.” It is this single pixel’s position that determines which UI element receives the click when the user presses a mouse (or trackpad, etc.) button. Because of the hot spot’s tiny size, it requires precision to hit a specific target on screen, especially if the target is small, too.1

Grossman and Balakrishnan address this problem by expanding the cursor’s “hot spot” to a circular “hot area.” The area’s size dynamically adapts to the cursor’s position in relation to nearby UI widgets so that, at any given time, exactly one widget is selected as the click target.

Grossman’s and Balakrishnan’s 2005 CHI paper (1.1MB PDF) explains the idea in detail and contains research which shows that the bubble cursor is consistently more effective than single-pixel and fixed-size area cursors.

Thanks to Anand’s JavaScript-based demo, you can try out the bubble cursor hands-on.

Unfortunately, though, you cannot disable or modify the area indicator around the cursor. It would be interesting to see whether changing the area indicator influences the feel of using the bubble cursor and, if so, in what way. I’d especially like to try out the demo without any visual feedback except highlighting of the current click target.

Found via Nat Torkington’s Four short links: 23 September 2010

Update 2010-10-05: Stuart Knightley has implemented the bubble cursor as a JavaScript bookmarklet that works with just about any webpage, so you can test this interaction concept in a real-life setting. As an extra feature not included in Kulkarni’s demo, this bookmarklet lets you toggle the display of the cursor’s click area.

  1. That’s Fitt’s Law at work again, of course. ↩

Evangelizing Usability at Ignite

When I decided to submit my first-ever Ignite presentation, I knew from the start that it would be about usability. After juggling a few topics for Ignite Fort Collins #6, I settled on “How Gestalt Psychology Can Help You Make Better High-Tech Purchasing Decisions.”

With only twenty slides and five minutes available per talk, you can barely begin to scratch the surface of something like Gestalt Theory. But five minutes do suffice to grab some of your audience’s mindshare and get them interested in learning more about your topic.

Which is where this blog post comes in, whose link is conveniently featured on the last slide of my talk.

How to gauge a product’s usability before you buy

The motivation behind the talk is to get average customers interested in the topic of usability. Why is it that similar products can provide very different user experiences? What is it that makes a product easy to use? How can I tell if a product will be easy to use before making a purchasing decision?

If this is something that interests you, my article, “The Ten Rules for Usable Technology,” is for you. It explains what good usability is, and how you can apply a set of simple rules to gauging a product’s ease-of-use before you part with your money.

More on Gestalt Theory

While the Gestalt Laws presented in my talk — Closure, Similarity, Proximity — are among the most important ones, Gestalt Theory extends way beyond these three. To learn more about this subject, here are three starting points for your intellectual journey.

A great introduction, presenting further Gestalt Laws, is presented in the first 45 minutes of this video from the Designing Interactive Systems 1 course from RWTH Aachen University.

Wikipedia’s article on Gestalt Psychology provides a concise overview over the topic including its history, fundamental principles, and the people behind it.

If you’re a designer who would like to get a feel for how to apply the Gestalt Laws to your work, read “The Rules of The Gestalt Theory And How To Apply It to Your Graphic Design Layouts” at the The All Graphics Design blog. This article also features lots of great example images.

Let’s put the pressure on

As I said in my presentation, there is no excuse for technology being difficult to use.

Usability has been a subject of scientific research for decades. Just being aware of something as — surprisingly intuitive — as the Gestalt Laws should enable product designers to make every one of their creations reasonably easy to use.

And yet, the spectrum of badly designed products ranges from simple alarm clocks that make it a pain to set the alarm time, all the way to smart phones that hide the number pad so successfully that average users have a hard time making a phone call…

By refusing to buy products that are difficult to use, every one of us can contribute to putting the pressure on high-tech companies and convince them of the value of good, human-oriented design.

Update 2010-09-24: Added YouTube video.

Don’t Move That Control!

Bill Waterson’s “Calvin and Hobbes” has been one of my favorite comic strips for years. Although I have quite a few of their wonderful books in my dead-tree library at home, in weak workday moments devoid of self-discipline, I sometimes check out the comic’s online version.

When I did so today, I noticed something odd: somewhat absentmindedly and occupied with other trains of thought, I repeatedly clicked on (what I assumed was) the “previous comic” navigation button.

Until, that is, I realized that, instead of moving backwards through older comic strips, I was actually going back and forth between only two of them. The reason? Bad UI design.2

When you point your web browser to the generic web link http://www.gocomics.com/calvinandhobbes, the website displays the most recent comic strip — you’re at the “end” of the publishing timeline. There are no more-recent comics than the one shown.

Consequently, the designer decided that not to display the navigation controls for moving “forward” along the comic’s timeline: the only available controls are for moving to the very first Calvin & Hobbes comic; for moving to the previous comic; and for bringing up a calendar widget.

As soon as you move to the previous comic, however, you also need controls for moving to the next strip, as well as for moving to the most-recently published one. The designer (correctly) placed these to the right of the calendar view to balance out the “first” and “previous” buttons.

Because the navigation buttons are right-aligned with the comic strip, though, the button for “next comic” ends up in the exact position that was occupied by the “previous comic” button before.

Unless you make up for this shift by moving the mouse pointer, you click on “next,” then “previous,” then “next” again, then “previous” again, and so forth.

Don’t hide. De-activate!

Just like in native software applications, unavailable UI widgets on web pages should be represented by grayed-out, un-clickable placeholders. That way, all controls remain in their original place at all times.

When implementing such a navigation widget, however, designers need to make sure that the whole group renders properly for all navigation states.

Here’s why that is important: the page navigation for Customer Reviews on the iTunes Store does use “de-activated” widgets for “previous” and “next” links. The ellipsis graphic is slightly narrower than the number buttons, though. As a result, when an ellipsis is displayed, the alignment of the buttons is slightly off. In case of two ellipses being shown, the “back” link slightly moves position, as well.

  1. Admittedly, my absentmindedness played a big role here, too, of course. I dare say, however, that this does not make the design any less problematic. ↩