I was expecting an article about DPI (as in raster printing dots), but it ended up being about PPI (as in screen pixels).<p>DPI in print is something I see many get wrong, and most don't understand the difference between DPI, LPI and PPI.
I find it hilarious that on a page about cross-platform design the left menu hides part of the article text on the ohh-so-common 1920x1080 displays.<p>I guess to some people cross-platform means "works on my imac 5K <i>and</i> my MBP retina"...
> This statement is true for the range of devices' screen size it's used in, but as the screens are getting better and better, our eyes are now trained enough to perceive the pixels - especially for rounded UI elements.<p>I'm not quite sure where this thinking has come in. The "Retina" moniker applies to displays based on the resolution, the size of the display and typical viewing distances for devices of that size and type. What science has suggested that our visual systems get better at resolving detail as display densities increase?
I know it's picky and this article is trying to be simplistic, but pixels do have a physical size. That is why there are optimal resolutions, starting with a 1:1 representation of physical to software.<p>Edit: Actually the first paragraph of "Resolution, pixel and physical size" kind of really causes confusion, since he is trying to redefine standard definitions, and then tries to provide reasoning for the redefinition. This is mainly a note of caution.
There is no date on this post, but few details point this to be bit outdated.<p>Lot of mobile assets are now svg (Android), pdf (iOS) or programmatically created. Most of the time if you design in Sketch, you don't really need to worry about the pixels since all the assets are in vectors. You can just spec everything in pt and export the assets in svg or in the desired 2,3x, whatver-x as needed.