Jakob Nielsen on Usability for Mobile Sites and Apps

What are the differences in user experience between the desktop and the mobile device?

I have pondered this question and come up with only basic and obvious answers, so I wanted to get an expert perspective. Imagine my delight when Jakob Nielsen of the Nielsen Norman Group agreed to speak with me. A founder of usability science, Nielsen has made giant contributions to our understanding of human-computer interaction. He’s one of my personal heroes. (Apparently I am not alone. I bragged on Facebook that I had interviewed him and got nine comments and five likes within minutes!)

First, I asked Nielsen to confirm my basic and obvious premise, that good usability is even more important for apps and mobile sites than for the desktop experience. Nielsen asserted that usability is important for everything, but life-or-death for low commitment experiences. If you buy a TV, the interface may not be optimal, but once you’ve installed this major purchase, you will take the time to figure it out. For a mobile site, the user has no commitment and other options are, literally, at hand.

For apps, the commitment is somewhat greater, since the user typically selects and downloads it, but it is still minimal. Nielsen said that when he and his team do usability testing for mobile, participants use their own phones rather than lab equipment. One of the first things the interviewer does is ask the participant to show what’s on the phone. As many studies confirm, users have apps they’ve used only once or forget downloading in the first place. While well-done push notifications can help overcome this obstacle, it won’t take the place of excellent usability.

In addition to the lack of commitment, there is a lack of focus. As I emphasize in “Mobile 101 training,” whatever your customers are doing on their phone, it is not their primary activity. They may be shopping and checking in, watching TV and monitoring sports scores, or dining and texting, but whatever the mobile activity, it is secondary.

In the app vs. site debate, Nielsen votes for the app, due to its faster speed and ability to take advantage of features like location, which improves the user experience (UE). “If you have enough customers and resources, do an app,” says Nielsen. (See also this great resource from the Global Intelligence Alliance, “Native or Web Application?“)

What are the biggest mistakes companies make when building their sites and apps?

1. Making it difficult to touch and manipulate. As Nielsen explains, your eyes are more agile than your fingers. You see that link among but your fingers can’t select it, so Nielsen recommends using larger touch targets.

2. Trying to do too much. Those responsible for the mobile UE must be ruthless when fighting internal political battles. Every department wants their content front and center, but when everything is prominent, nothing is prominent, so eliminate the nice-to-have.

Nielsen argues for fewer commands and a few basics on first screen. Use progressive disclosure to build the experience, rather than try to put every option up front. More screens are better if each is simple and focused. Include a button to full site for those who need more content than makes sense for the mobile version.

When it comes to copy, short is too long. It must be ultra-short.

Without context, Nielsen reports, comprehension is degraded. While our brains are great for long-term storage, they fail in the short term. For this reason, people will not use mobile for research or comparing large amounts of information. Don’t require a user to remember things from screen to screen.

According to Nielsen, the primary drivers of mobile usage are time, location, and killing time. “Killing time is the killer app for mobile.” Develop use cases. Don’t fall into trap of following the crowd; make it align with your brand strategy. If your brand is practical and straight-forward, for example, don’t try to make your app “fun.”

Enhance your brand with exceptional usability. Those developing the app or site aren’t qualified to evaluate it, as you can’t turn off your insider perspective, knowing what users are supposed to do. Enlist usability experts to test your UE prior to launch and avoid those nasty one-star comments in the app store.

As Nielsen states in this app makeover article, “User experience is branding in the interactive world.”

This column was originally published on Aug. 12, 2011 on ClickZ.

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A QR code which leads to the URL for the ClickZ article about QR codes. Meta.