Screen size, resolution and quality are some of the most important features to consider when choosing a smartphone.
Vivo Y11 (2019)'s 6.35" IPS LCD is slightly larger (0.15" ) than the Oppo A5's 6.2" IPS 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).
Oppo A5 and Vivo Y11 (2019) have exactly the same display coverage of 81%- so we don't have a winner here.
Screen size is only one side of the story, resolution is as important in most cases.
Oppo A5's 271ppi pixel density is only slightly higher (3ppi ) than the Vivo Y11 (2019)'s 268ppi pixel density.