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handle significant variation in volume or will responsiveness drop dramatically? It is not
enough to build a WebApp that is successful.
• Time-to-market. Although time-to-market is not a true quality attribute in the technical
sense, it is a measure of quality from a business point of view. The first WebApp to
address a specific market segment often captures a disproportionate number of end users.
Tillman suggests a useful set of criteria for assessing the quality of content:
• Can the scope and depth of content be easily determined to ensure that it meets the
user’s needs?
• Can the background and authority of the content’s authors be easily identified?
• Is it possible to determine the currency of the content, the last update, and what was
updated?
• Are the content and its location stable ?
In addition to these content-related questions, the following might be added:
• Is content credible?
• Is content unique? That is, does the WebApp provide some unique benefit to those who
use it?
• Is content valuable to the targeted user community?
• Is content well organized? Indexed? Easily accessible?
DESIGN GOALS
Jean Kaiser suggests a set of design goals that are applicable to virtually every WebApp
regardless of application domain, size, or complexity:
• Simplicity. Although it may seem old- fashioned, the aphorism “all things in moderation”
applies to WebApps. There is a tendency among some designers to provide the end user
with “too much”— exhaustive content, extreme visuals, intrusive animation, enormous
Web pages, the list is long. Better to strive for moderation and simplicity. Content should
be informative but succinct and should use a delivery mode (e.g., text, graphics, video,
audio) that is appropriate to the information that is being delivered.
• Consistency. This design goal applies to virtually every element of the design model.
Content should be constructed consistently should present a consistent look across all
parts of the WebApp.

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• Identity. The aesthetic, interface, and navigational design of a WebApp must be
consistent with the application domain for which it is to be built.
• Robustness. Based on the identity that has been established, a WebApp often makes an
implicit “promise” to a user. The user expects robust content and functions that are
relevant to the user’s needs. If these elements are missing or insufficient, it is likely that
the WebApp will fail.
• Navigability. I have already noted that navigation should be simple and consistent. It
should also be designed in a manner that is intuitive and predictable.
• Visual Appeal. Of all software categories, Web applications are unquestionably the most
visual, the most dynamic, and the most unapologetically aesthetic. Beauty (visual appeal)
is undoubtedly in the eye of the beholder, but many design characteristics (e.g., the look
and feel of content; interface layout; color coordination; the balance of text, graphics, and
other media; navigation mechanisms) do contribute to visual appeal.
• Compatibility.