> 160dpi is considered the baseline for screen pixel density, since it’s a 1:1 screen-pixel to device-pixel ratio.
Things are a bit more complicated here. The CSS Media Queries spec operates the “CSS inches”, not physical inches (https://www.w3.org/TR/css3-mediaqueries/#resolution0), and “CSS inch” is *defined* to be equal to 96 CSS pixels. That’s why iPhones would report that they have 192dpi (despite having 326 pixels per *physical* inch), and it’s 96dpi that is considered the baseline, although the typical *physical* resolution of most mobile devices is significantly higher. Yes, it’s very counter-intuitive, but so is the CSS standard.