However, the iPad mini packs more pixels per inch, giving it a 326 ppi as opposed to the iPad Air's 264 ppi. (laptopmag.com)
While I wish the iPad's display packed a few more pixels per inch (it boasts 132 ppi, compared to the iPhone's 163 ppi), I find that — just as the Kindle does — the device really fades away after a few pages. (macworld.com)