Smartphone shipments in the United States were down -12% annually in Q3 2018, as the market matured and upgrades replacement rates for smartphones slowed. Apple was number one in hardware, while Android captured top spot in software. T Mobile delivered a great performance. This report tracks smartphone shipments, vendor marketshare, and OS marketshare for 20 major brands and 4 major platforms in the United States across 4 top operators and the total market on a quarterly basis from Q1 2011 to Q3 2018. Operators covered include Verizon Wireless, AT&T, Sprint and T Mobile.