No-contract strategy attracts customers

China's ZTE Corp is getting the jump on its rivals in the no-contract mobile phone market by transforming itself into a smartphone maker that big US carriers can no longer take for granted.

ZTE's 85.7 percent surge in first-quarter sales compelled research firm Strategy Analytics to name it the fastest-growing US smartphone vendor of the past year. ITG Market Research ranked the Shenzhen-based maker of telecommunications gear the third-largest US smartphone maker, with 17 percent of the nation's prepaid handset market, trailing only South Korea's Samsung Electronics Co and California's Apple Inc.