From Nexus 5X spec it has 411x731 dp screen size.
How I understand that:
If I want recycler view with 2 column in portrait mode I should define column_count value in dimens.xml
mdpi device 1dp = 1px, and
mdpi corresponds to 160 lcd density. The Nexus 5x has an lcd density of 480 (as specified in
/system/build.prop), so on that device 1dp = 3px (because 480/160 = 3). The screen dimensions are 1920x1080 pixels, so divide by 3 and you get 640x360 dp (or 360x640 dp in landscape). Seems to me the device is acting perfectly fine.
-sw720 matches large tablets, and
-sw600 matches smaller tablets (and sometimes very large phones).