Screen size, resolution and quality are some of the most important features to consider when choosing a smartphone.
Samsung Galaxy S5's 24 Super AMOLED and Samsung Galaxy S6's Super AMOLED screen have exactly the same LCD size of 5.1" so we don't have a winner here.
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).
Samsung Galaxy S5 and Samsung Galaxy S6 have exactly the same display coverage of 70%- so we don't have a winner here.
Screen size is only one side of the story, resolution is as important in most cases.
Samsung Galaxy S6's 576ppi pixel density is significantly higher (144ppi ) than the Samsung Galaxy S5's 432ppi pixel density.