* Samsung gears S9 toward easy use of visual applications
* S9 forecast to sell 43 million units in 2018-Counterpoint
* Global smartphone shipments tumbled 9 pct in 4Q
* Samsung faces competition, lost ground in India, China in Q4
BARCELONA/SEOUL, Feb 25 (Reuters) - Samsung Electronics Co Ltd unveiled its flagship Galaxy S9 smartphone on Sunday with an emphasis on visual applications for social media, hoping to attract tech-savvy young consumers to weather a market slowdown.
With the global smartphone market set to stay flat or even shrink after meager growth of one percent last year, vendors are focusing on features designed to encourage young consumers to ditch their old phones earlier than they would have previously.
Samsung, the world's biggest smartphone maker, showcased the Galaxy S9 at a mobile gadget fair in Barcelona. It features improved cameras, an artificial intelligence-powered voice tool, and social media functions that are easier to deploy than previous offerings.
New features include an automatic super-slow motion camera setting that looks primed to show up on Instagram feeds soon, and software that turns selfies into instant emojis.
Samsung's AI-powered Bixby service allows S9 users to point its camera to translate a foreign-language sign, without having to swipe through menus or choose settings every time.
Samsung also plans to boost smartphone accessories such as wireless chargers and mobile docking station that allows smartphone features on desktop, a senior Samsung executive said.
Younghee Lee, head of Samsung's Marketing for the Mobile Business, declined to provide a sales forecast for the S9.
Research firm Counterpoint forecasts it will sell 43 million sets in 2018, 23 percent more than the 35 million S8 models shipped last year.
Global smartphone sales saw an unprecedented decline of 9 percent in the fourth quarter, averaging 2017 growth to just 1 percent, a far cry from growth of about 40 percent between 2011 and 2015, according to research provider Strategy Analytics.
While Samsung kept its supremacy over Apple Inc with about 21 percent of market share, Counterpoint says, it faces tough competition after it lost ground in markets like India, China and Western Europe in the fourth quarter. Chinese rivals such as Huawei Technologies Co Ltd and Xiaomi Inc are making major inroads in such markets, aided by strong sales of affordable products that boast many high-end features and sturdy design.
Lee said Samsung's huge scale and its "agility to listen and learn" ensured it would continue to grow in China and India.
The two versions of the Galaxy S9 have 6.2-inch (15.8 cm) and 5.8-inch wrap-around screens, and will go on sale on March 16 in most countries. (Reporting by Joyce Lee; Editing by Miyoung Kim and Stephen Coates)