PUBLIC MARKS with tag webdev

Taking a “mobile first” approach to web development poses some challenges if you need to provide a “desktop” experience for legacy versions of IE. Using a CSS pre-processor like Sass can help.

For three generations of the iPhone, Apple kept the screen consistent (320x480 pixels and 3.5 inches diagonal). But now Apple's new iPhone 4 boasts the "highest resolution phone screen ever (960x640 pixels, 3.5 inches diagonal, & an 800:1 contrast ratio)." What's the impact to designers?

As a real world example of how big the impact can be on performance, I made a test with the full HTML5 specification downloaded locally and ran the profiler. I noticed few of the most expensive selectors had ":link" and ":visited". I changed these to instead be "a:link" or "a:visited" (in this case they were equivalent in terms of which elements matched). This trivial change makes the engine use a cache, and bought the selector matching time down from about 14 seconds to about 11 seconds.

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