Samsung Electronics Co Ltd unveiled a new Galaxy Note phablet and a larger version of its curved-screen S6 edge smartphone on Thursday, marking a fresh bid by the South Korean tech giant to revive momentum in its handset business. Samsung is the world's top smartphone maker but its market share fell in the second quarter when its critically acclaimed S6 models launched, squeezed by Apple Inc's upscale iPhones and cheaper offerings from Chinese rivals such as Huawei Technologies Co Ltd [HWT.UL].