Interesting comparison, but fundamentally flawed. I think Hex overlooks something essential: how the fonts are rendered by the OS. Each of these operating systems uses different anti-aliasing algorithms — even Mac OS X (which uses sub-pixel anti-aliasing by default) and iOS (which never uses sub-pixel anti-aliasing). A proper comparison should show these fonts as they are rendered on each system.
His criteria are too analytical. You want to know why I think Helvetica Neue is a great UI font for iOS? Because it’s beautiful. And the problem with the font that “wins” his comparison, Droid Sans, is that it’s ugly. You know it’s ugly when even Google thinks it is.
Update: Also not considered: the displays of the devices in question: resolution, IPS/LED vs. AMOLED, etc. Apple, for example, uses Helvetica, not Helvetica Neue, as the system font on non-Retina displays. Why? Because it renders better at a lower resolution.
★ Wednesday, 2 November 2011