Dan SafferSaffer is the founder of Kicker Studio, a San Francisco-based design consultancy. He is the author of two books, Designing for Interaction and Designing Gestural Interfaces.

What’s the connection between content and interaction design? How do you take into account the product’s ultimate function – whether it’s entertainment or information delivery or communications – in the design process?

If we think of content in a broad sense, most interactive products have to do with content: either consuming it (watching an online slideshow), generating it (digital cameras), manipulating it (Photoshop), or some combination of those (social network sites like Facebook). For interaction designers, the important thing is to consider what it means to do one of these activities in the context of use, and design for that.

On the consumption end of the spectrum, often the interaction designer’s job is simply one of providing tools to find and navigate the content structure and to get the hell out of the way. On the generation and manipulation side of the spectrum, it’s a lot more complex, because sometimes the focus is on the tool itself, not just the content.

What effect does or should the aircraft environment have on interaction design? How do you account for tangibles like ambient lighting levels and less tangibles like user frame of mind?

Interaction design is all about behaviour, so things like lighting levels can affect that, helping put travellers into a different state of mind so that different behaviours seem acceptable or expected. Think of the cool violet lighting inside a Virgin America aircraft for instance. And certainly products like the back-of-the-seat touchscreen systems have changed life for the better for travellers by giving them a modicum of control in a situation that used to be entirely regimented.

The addition of the touchscreens can change the way processes have traditionally worked. To use another Virgin America example, the ability to directly order food and drinks from your seat whenever you want pretty much eliminates the need for beverage and meal service.

Virgin America's inflight system via TravelPost.com

Ordering drinks on Virgin America's inflight system

What are your thoughts on the proliferation of interactive terminals for travellers—I’m thinking of everything from airport check-in terminals to tourist visitor centres to subway ticket counters. Do you think travellers have been adequately served by interaction designers in this context? Is there any area where person-to-person interaction is always better?

I think they’re great. They are the best additions to a massive service since ATMs became part of banking. Travellers have been well served by them, I think, and are getting better served every day, with online and mobile applications in addition to kiosks. Of course, like with ATM and bank tellers, there are situations too complex for the regular system to handle; sometimes you just need a person to explain a situation to, and they can use the more powerful tools at their disposal – as well as their knowledge of the system – to address complex problems. Not everything can be turned into hardware/software. Nor should everything be – major systems like transportation are so complex, it takes humans to work them.

What are some ways that brands can engage users through interactive interfaces? What are some examples of effective engagement, and where have people been turned off?

The simple answer to this is to make great products that meet people’s needs and that they enjoy using. That will make a positive connection in customers’ minds to the brand. Of course, that’s really hard.

I think it’s important for companies to remember that, except in some rare circumstances, customers aren’t there to “experience your brand”. They are there to do something. If you make it easy and pleasurable to do those activities, it creates brand loyalty. If even a fraction of the money spent on marketing and advertising was spent to make interactive products better, you’d see a huge improvement.

You can see effective engagement in products like the iPhone, TiVo, Facebook, Twitter. They are all products people use and then advocate for. You can tell bad products because people quickly tire of them or are reluctant to use them unless necessary. Products that are ugly and poorly thought out. We’re surrounded by this stuff all the time.

Well Fargo's popular ATM interface

Well Fargo's popular ATM interface

Are gestural interfaces going to replace touch screens or other traditional interfaces? Are they simply a more advanced technology or is there still a place for good old push buttons?

To paraphrase Bill Buxton, all technologies are good for some things and bad for others. I imagine a future – a near future – where gestures, touchscreens, and mechanical/physical interfaces all exist side by side, used when and where appropriate based on the context of use. Take public restrooms, for instance. Gestural interfaces (in sinks, paper towel dispensers, hand driers, etc.) seem to have taken root there, in part because it makes both practical (because the less you touch in public bathrooms, the better) and business (it saves water, paper, and electricity) sense. Touchscreens and certainly not keyboards and mice don’t belong there. Likewise, I don’t see keyboards vanishing from offices anytime soon, because they are quite good for doing large amounts of data and text entry. I think we’re still in the process of finding out what gestural interfaces are good for, really.

Are gestural interfaces culturally sensitive? Is the iPhone as “intuitive” for someone in China or India as it is for someone in San Francisco?

Gestures certainly are culturally sensitive. The OK sign, for instance, is very offensive in certain parts of the world, as is a thumbs up. Touchscreen products have their own interaction design language that has to be learned, the same way there is a language on the desktop software (“cut and paste,” for instance). The hope is that there is less of a learning curve for products that are manipulated directly with the fingers than with a mouse or via menus. I don’t know if that is necessarily true, but anecdotally we keep hearing about children as young as two picking up iPhones and figuring them out. If children who can’t read can use something, it should translate across borders pretty well.

You edit a blog called No Ideas But In Things where you feature mechanical interfaces that inspire you. What are some of your favourite interaction designs from the physical world?

I really love controls for heavy machinery like cranes, bulldozers, and the like. There is something about their bluntness and clarity that all designers can learn from. Plus, the icons are incredible. Since a lot of the operators now don’t read English, there are more icons than words. My favourite was a Fast/Slow lever that had a rabbit on one side and a turtle on the other. Genius.

Hospital bed controls via No Idea But In Things

Hospital bed controls via No Idea But In Things

Are there any everyday appliances that you think ought to be completely redesigned? Is there a point of no return at which the way something works becomes so intuitive to most people that it can no longer be reconfigured?

Most of the appliances we have now have been refined over decades, so there are probably only incremental changes we’re going to see to them. Although who knows? I’d love to design a gestural stove. And the initiative to be more environmentally friendly may cause some changes in food preparation and storage that require new appliances.

It’s more likely we’re going to see the interplay of our appliances, and them becoming smarter and more aware. Dishwashers running when energy is the cheapest, for instance. Stoves that detect burning and lower the heat.

I don’t think there is ever a point when a product can’t be improved. Forks, for instance, evolved over several centuries. But the TV, for instance, was a fairly stable technology until DVRs disrupted the service.

What are the differences between designing for the stressed commuter, rushed businessman, Luddite senior citizen, multitasking teen, etc.? Do you aim for the lowest common denominator when designing a user interface, or for a specific demographic?

You might have all these seemingly diverse groups, but they might all have the same expectations, motivations, and behaviour. Those are the three key components to think about when designing. When there is variation in those, you have to figure out how much the interface has to adjust for. In some circumstances, like for public transit ticketing machines, it is designing for the widest acceptable range. For many other products, that’s not the case at all. You target one set of expectations, motivations, and behaviour and that is your product. Other products are made from other sets of those characteristics.

What are some common mistakes you’ve seen in other people’s designs? Any pet peeves?

Emphasizing the wrong button is one I see frequently. Drives me crazy. Squint at the screen or the device and see what is the most prominent item. If it isn’t supposed to be the most important control, the design is likely wrong.

Saffer’s presentation on gestural interfaces at the Interaction Design Association (IxDA) conference in New York City