Mobile marketing analyst Flurry have unveiled their latest study, which draws samples from around one billion smartphones and some 2,000 unique device models worldwide. The study looked at both the distribution and usage by end-users of the top 200 device models, and found that "medium phones" with 3.5- to 4.9-inch screens were far and away the dominant choice in both areas. Phones with smaller screens were steadily declining in usage as buyers upgrade, and smaller tablets and "phablet" phones have yet to make much end-user headway.