Mobile usability

Mobile sites have higher measured usability than desktop sites when used on a phone, but mobile apps score even higher.

Jakob Nielsen

Interface chrome

“Chrome” is the user interface overhead that surrounds user data and web page content. Although chrome obesity can eat half of the available pixels, a reasonable amount enhances usability.

J.Nielsen’s Alertbox

3 mathematical laws and their implication for usability

According to Thomas Baekdal, usable sites/apps are fast, efficient, simple, (and focussed).

• Fast is connected to “GOMS keystroke model”
  “The fewer times you click on something and the fewer times you move your hand between the keyboard and the mouse, the faster it is to use”.
• Efficient is connected to “Fitt’s Law”
  “A large target close to you, is easier to hit than a small target far away”
• Simple is connected to “Hick’s Law”
  “The fewer choices you have, the easier it is to choose between them”

How many participants?

‘Over the years, there has been plenty of debate over how many participants are enough for a study. It turns out we were looking in the wrong direction. When you focus on the hours of exposure, the number of participants disappears as an important discussion. We found 2 hours of direct exposure with one participant could be as valuable (if not more valuable) than eight participants at 15-minutes each. The two hours with that one participant, seeing the detailed subtleties and nuances of their interactions with the design, can drive a tremendous amount of actionable value to the team, when done well.’

JARED M. SPOOL: Fast Path to a Great UX – Increased Exposure Hours

Don Norman: How to make complex things easy to use (German)

SPIEGEL ONLINE: Gibt es allgemeingültige Regeln, um das zu erreichen?

Norman: Klar! Teil die Dinge in Einzelteile auf, organisiere diese Teile, strukturiere sie. Gib Feedback. Ich will immer wissen, was gerade und warum passiert. Durch eine gute Struktur kann ich mich immer nur auf eine Sache konzentrieren. Letztlich geht es darum, aus einem scheinbar undurchschaubaren Technik-Kuddelmuddel etwas schlüssiges und verständliches zu machen.Sache konzentrieren. Letztlich geht es darum, aus einem scheinbar undurchschaubaren Technik-Kuddelmuddel etwas schlüssiges und verständliches zu machen.

Don Norman in an interview with SPIEGEL ONLINE

In summary:

1. Break down into distinct parts
2. Organise and structure these parts
3. Give feedback

Touch/gestural interactions: lack of discoverability

Nielsen says that some of the iPad’s problems are endemic to the touch tablet format. “With the iPad, it’s very easy to touch in the wrong place, so people can click the wrong thing, but they can’t tell what happened,” he says. There are also problems with gestures such as swiping the screen because they’re “inherently vague”, and “lack discoverability”: there’s no way to tell what a gesture will do at any particular point.

“People don’t know what they can do, and when they try to do something, they don’t even know what they did, because it’s invisible,” Nielsen explains. “With a mouse, you can click the wrong thing, but you can see where you clicked.”

Jack Schofield: Jakob Nielsen critiques the iPad’s usability failings

Don Norman: ‘Natural interfaces’ are not natural

…
Most gestures are neither natural nor easy to learn or remember. Few are innate or readily pre-disposed to rapid and easy learning. Even the simple headshake is puzzling when cultures intermix. Westerners who travel to India experience difficulty in interpreting the Indian head shake, which at first appears to be a diagonal blend of the Western vertical shake for “yes” and the horizontal shake for “no.” Similarly, hand-waving gestures of hello, goodbye, and “come here” are performed differently in different cultures. To see a partial list of the range of gestures used across the world, look up “gestures” and “list of gestures” in Wikipedia.
…
Gestures will become standardized, either by a formal standards body or simply by convention–for example, the rapid zigzag stroke to indicate crossing out or the upward lift of the hands to indicate more (sound, action, amplitude, etc.). Shaking a device is starting to mean “provide another alternative.” A horizontal wiping motion of the fingers means to go to a new page. Pinching or expanding the placement of two fingers contracts or expands a displayed image Indeed, many of these were present in some of the earliest developments of gestural systems. Note that gestures already incorporate lessons learned from GUI development. Thus, dragging two fingers downward causes the screen image to move upwards, keeping with the customary GUI metaphor that one is moving the viewing window, not the items themselves.
New conventions will be developed. Thus, although it was easy to realize that a flick of the fingers should cause an image to move, the addition of “momentum,” making the motion continue after the flicking action has ceased was not so obvious. (Some recent cell phones have neglected this aspect of the design, much to the distress of users and delight of reviewers, who were quick to point out the deficiency.) Momentum must be coupled with viscous friction, I might add, so that the motion not only moves with a speed governed by the flick and continues afterward, but that it also gradually and smoothly comes to a halt. Getting these parameters tuned just right is today an art; it has to be transformed into a science.
…
It is also unlikely that complex systems could be controlled solely by body gestures because the subtleties of action are too complex to be handled by actions–it is as if our spoken language consisted solely of verbs. We need ways of specifying scope, range, temporal order, and conditional dependencies. As a result, most complex systems for gesture also provide switches, hand-held devices, gloves, spoken command languages, or even good old-fashioned keyboards to add more specificity and precision to the commands.
…
Gestural systems are no different from any other form of interaction. They need to follow the basic rules of interaction design, which means well-defined modes of expression, a clear conceptual model of the way they interact with the system, their consequences, and means of navigating unintended consequences. As a result, means of providing feedback, explicit hints as to possible actions, and guides for how they are to be conducted are required. Because gestures are unconstrained, they are apt to be performed in an ambiguous or uninterruptable manner, in which case constructive feedback is required to allow the person to learn the appropriate manner of performance and to understand what was wrong with their action. As with all systems, some undo mechanism will be required in situations where unintended actions or interpretations of gestures create undesirable states. And because gesturing is a natural, automatic behavior, the system has to be tuned to avoid false responses to movements that were not intended to be system inputs. Solving this problem might accidentally cause more misses, movements that were intended to be interpreted, but were not. Neither of these situations is common with keyboard, touchpad, pens, or mouse actions.
…

From: Don Norman Natural interfaces are not natural

Pete Gale (cogapp): Usability issues with maps

From the ‘Wayfinding’ talk at UX Brighton 9.2.2010; Pete talks about experiences from user testing tfl related sites/apps

When developing wayfinding tools such as maps, consider:
• Attitudes
  People do have attitudes amongst maps, not everybody likes them
• Interaction
  People do not necessarily read affordances provided in the map (eg dragging with the hand)
• Information
  Too much information can obscure the map; information as clutter and noise; consider density of information and level of detail
  Often, the journy is less important than actual information around the start and the end point of a journey
  Examples: Mapumental
• Wayfinding
  Discrepancey of how the world is represented on a map and how it is perceived by people; example: people usually do not use street names to decribe a journey, but landmarks; problem: how can landmarks be described adequately; problem of crowdsourcing ‘popular’ information: data are dirty; think of simplicity vs. complexity, concrete vs. abstract
  Examples: Legible London; Here & There

The pain of pagination

It’s always worth re-visiting ‘best practices’ that are for the most part never being really questioned. Pagination is a good example. While discussing pagination with developers, I got the impression that it is (or it used to be) a best practice for technical reasonsmore than it is based on actual user insight. There are some obvious (technical) benefits of returning database query results in chunks: it allows quick page load, saves bandwidth, server resources, and energy. It allows designers to apply efficient page grids and to send relevant information into the footer. Oh, and it adds some page-impressions to your SEO statistics.

But what about the user? From what I see and hear in usability test session, users don’t like it and don’t really use it. Although modeled on the simple and very familiar pattern of turning book pages (well, may be not that familiar anymore?), pagination works well only for users who are willing to make an effort. Page-turning on the Web is a complex operation involving a series of cognitive and physical steps: understanding the idea of pagination, allocating the pagination bar, understanding the next step required (where am I and where do I want to go), locating and hitting a (more often than not) tiny link.

Most users seem to be satisfied with a limited number of results anyway. This is certainly true for Google-like search results or for all other ‘transient data’ (Scott 2009, p. 155), where data further down the line become less relevant for the user. But what, for example, if you want to check this season’s trendiest trainers that happen to be a list of 123 items in no particular order – and you don’t want to miss any of them? Comparing items across different pages is painful and ineffective. The product pages of the Adidas online shop employ an alternative to pagination that addresses user needs without straining server resources. Content is incrementally loaded on demand, i.e. when the user scrolls through the page. With a bit of buffer, this works very well. Incremental page load (or yahoo-style crolling) requires new thinking around page-layout and meaningful tools, but for many use cases it promises the end of clumsy page poking and the pain of pagination.

Other examples:
Globrix property search
Artists page of Bandcamp (combining incremental page load with pagination)

5 Core usability principles

Usability principles – it’s probably been said a thousand times, with far too many words. This is my take on it:

1. Accessibility
   Interfaces that do not comply with average accessibility standards will most likely cause usability issues for everybody.
2. Visibility
   In digital systems, everything is hidden by default. If something is not visible or made explicit, I cannot use it.
3. Consistency
   Almost every visit of a site involves some learning (which is good). Within one site or application, however, I do not want to unlearn or re-learn the visual language, the labels, or the underlying structure.
4. Hierarchy
   Visual hierarchy and semantic hierarchy allows me to quickly establish a logical system and to carry out tasks quicker.
5. Recoverability
   It’s great to be able to do smart things. It’s essential, however, that I am made aware of any changes made (feedback) and that I easily can reset a default/previous state (recover).