(Telecompaper) Samsung has announced the appointment of Dongjin Koh as president of its mobile communications business, Reuters reported. Koh will take over the struggling smartphone business from JK Shin, who will remain head of the overall mobile division for Samsung Electronics and focus on long-term strategy and developing new growth businesses. The move diminishes Shin's influence on the mobile business as the division looks to reverse a slide in its market share. In addition, Samsung wants Yoon Boo-keun, the head of its TV and appliances division, to take on a more strategic role. All the changes were made under Jay Lee, who has virtually taken over the reins at Samsung since his father and group patriarch, Lee Kun-hee, was hospitalised following a heart attack last year.