Resolution Independence and the Mac
Dr. Drang has a post (now fireballed) bemoaning the large difference in resolution between desktop, notebook, and ultraportable Macs. There is indeed a wide range, from 102 ppi on the 21.5” iMac to 135 ppi on the new 11” MacBook Air. Apple has been working on resolution independence for awhile, but thus far it’s been too buggy to unleash on the general public. Lately those efforts seem to have stalled, at least as far as public announcements go. There are a couple of reasons why this might not be such a bad thing.
First, the different displays mentioned above are typically used at different distances. I’m typing on a 27” iMac, with the display at a distance where I can very nearly (but not quite) reach out and touch it. It wouldn’t be physically possible for me to type on a laptop at this distance, at least with the built-in keyboard.
Controls really ought to occupy a fixed number of arc-seconds of one’s visual field based on typical usage. That way, regardless of screen size and working distance, they occupy the minimum amount of screen real-estate necessary to be readable. The WYSIWYGness of what’s displayed on the screen only becomes an issue when you want to gauge what a document will look like printed. So the important parts of this sort of resolution independence can be (and mostly are) implemented in individual print-media creation apps.
The second reason is that resolution independence might soon become moot. Displays are rapidly becoming too high-res for a person to distinguish individual pixels: the iPhone 4 already achieves this at typical smart-phone viewing distances, and I would argue that my iMac and the new 11” Air are, if not already there, really close (at their typical viewing distances). If and when desktop and notebook displays reach Retina Display resolution, Apple could simply declare that 320 is the new 72 and be done with the whole resolution independence quagmire for good.
A caveat is that some people (particularly those my age and older) are going to want larger controls on an arc-seconds-of-visual-field basis. That in itself might make resolution independence worth fighting for.