Screen size, resolution and quality are some of the most important features to consider when choosing a smartphone.
BlackBerry Z30's 5" Super AMOLED screen is significantly larger (1.5" ) than the BlackBerry Classic Q20's 3.5" TFT screen.
Besides comparing the LCD sizes, another specs that we find useful to compare is the ratio of screen area to total surface area of the phone (screen area/total surface area).
BlackBerry Z30's 5" screen covers 70% of its surface area, on the other hand BlackBerry Classic Q20" display covers only 40% of its total surface.
Screen size is only one side of the story, resolution is as important in most cases.
BlackBerry Z30's 294ppi pixel density is only slightly higher (3ppi ) than the BlackBerry Classic Q20's 291ppi pixel density.