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General: Least Common Denominator

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  • XHTML MP 1.0 Compliant
  • JPG & GIF Support
  • 256-color Support
  • 120 x 120 Minimum Resolution

The UCLA Mobile Web Framework works with the least common denominator of an XHTML MP 1.0 compliant device with JPG, GIF, 256 colors and a minimum screen resolution of 120 x 120. This baseline is a joint definition based on the W3C Mobile Web Best Practices and the Global Authoring Practices for the Mobile Web standards. While most of these requisites are fairly straightfoward, the choice of XHTML MP 1.0+ (WAP 2+) stems from the fact that even basic XHTML markup will not necessarily degrade to WML (WAP 1.x) effectively, and thus one would have to build separate WML pages to support WAP 1.x, which is nearly an end-of-life standard in mobile devices at this time.


The use of markup that degrades in all devices that meet the least common denominator allows developers to build pages that, regardless of CSS, Javascript,etc., still conveys the intended purpose of the markup. Similarly, following such standards allows one to ensure the organizational structure of the page makes sense even when CSS is not loaded.

An example is a menu. In touch screens and above, let's say we want the menu horizontally-oriented. If we had an class defined in the touch screen CSS, for these browsers we could orient the rows horizontally. In linear CSS-capable devices, we could still style the lists, but they would not support horizontal listing, so we'd leave ordered and potentially numbered in the base CSS (we wouldn't define an in this base CSS, but just an <ol>). Then, at the lowest level, because we've picked <ol>, the non-CSS browsers would still allow for the click-through of items (and by using <ol> we get access key functionality).


This standard for a least common denominator was leveraged from a combination of works from the W3C Mobile Web Best Practices guide, the Global Authoring Practices for the Mobile Web and MIT's Mobile Web Consortium, as well as addition work done by the framework collaborative group.

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