I have always said that usability is not the same as a nice looking design. Usability is even different form user experience. Of course, it’s an all day discussion just to agree on the terms… So let me try to explain my views.

The success of a mobile website or mobile application totally relies on its usability. Usability is an umbrella term, considering information architecture, affordance, interaction design and, to some extent, design. A mobile web site can have a crappy design, but still be very usable. (On the web, my fav example is Norways largest online newspaper vg.no (The site is still compelling, but the design is not world class, top modern) ) So, thats my definition. But now to my point.

Usability patterns applied on a desktop web site cannot be ported to mobile and be expected to work well! This is where the confusion starts. Web designers tend to know some things and tricks about usability on desktop web. But in most cases this knowledge is useless on mobile.

Why? Because usability in mobile is more about HCI than web design. On the web the interaction model is simple and uniform across platforms; the mouse and keyboard. General design approaches applies to a greater extent on desktop due to this interaction model and the fact that the screen is bigger. It makes sense to present a “flyer design” or “brochure look” on a desktop website. And it might even be very usable, user friendly, have a cool design and provide good user experience.

On mobile on the other hand, the interaction model is very different and more fragmented. The same goes for screen size. This is my main argument for approaching design of mobile sites or apps from a HCI perspective and not a design perspective.

The counter argument I meet is “But look at Apple iPhone. They have the coolest design ever”. Yes, true. But they have also revolutionized the way the user interacts with both mobile web sites and apps by introducing new controls, navigational patterns and, most importantly, removing an abstraction level by the introduction of the touch screen. With the touch screen you are actually interacting with the site/application it self, compared to desktop web where you have the mouse and keyboard and on other mobile devices where you have joysticks, arrow keys, stylus etc.

The HCI approach to mobile design considers this difference. So, what I am saying here is that if you want a kick ass mobile web site or app, hire a HCI expert, not a designer.

….or if you stumble upon HCI expert with design expertise, hire him/her today and double their salary!