Samsung Electronics Co., the world's largest smartphone maker, is losing its dominance in Taiwan's phablet market after rivals launched more big-screen handsets larger than 5.5 inches, according to data research firm IDC. The South Korea electronics giant garnered more than 80 percent of phablet shipments in Taiwan in 2013 thanks to its successful Galaxy Note series, but its share plunged to 33 percent last year in the face of mounting competition from Apple Inc. and smaller players, IDC said in a recent report.