According to our Handset Country Share Tracker (HCST) research service, smartphone shipments in the United States jumped an impressive +33% annually in Q4 2014, driven mainly by Apple which had a blockbuster quarter. Apple was number one in hardware, while Android captured top spot in software. T Mobile delivered a great performance, as its smartphone volumes soared to their highest level of all time. Its Un-carrier strategy is proving successful. Our extensive report -- available to clients here -- 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 Q4 2014. Operators covered include Verizon Wireless, AT&T, Sprint and T Mobile.