
Site Detection ◾ 33
via the mobile web are not the same as screen pixels. Retina
®
devices in
the iOS platform introduced the practice of doubling pixel density (e.g.,
iPhone
®
3GS vs. 4, iPad
®
2 vs. 3). e retina Mobile Safari user- agents
continue to report the same device width to avoid breaking the web. As
other devices, like Android, deploy higher- resolution displays, they are
employing the same device- width trick.
We must consider both landscape and portrait modes. Each time the
device is reoriented, we do not want to reload the page or load additional
scripts, though we may choose to render the page inversely. Figure 2.7
illust