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* S4 unveiled at Manhattan's Radio City Music Hall
* S4 bristling with new control, gesture and navigationfeatures
* Will be available by the end of April
By Sinead Carew and Miyoung Kim
NEW YORK/SEOUL, March 15 (Reuters) - Samsung Electronics Co premiered its latest flagship phone, the Galaxy S4,which sports a bigger display and unconventional features suchas gesture controls, as the South Korean titan challenges AppleInc on its home turf.
The phone, the first in the highly successful GalaxyS-series to make its global standalone debut on U.S. soil, wasunwrapped at Manhattan's iconic Radio City Music Hall onThursday evening. Some industry watchers were clearly dazzled byits features, setting a high bar for Apple to surpass.
The S4 can stop and start videos depending on whethersomeone is looking at the screen, flip between songs and photosat the wave of a hand, and record sound to run alongside snappedstill pictures. But other industry watchers said the phone wouldnot overturn an industry that lives and dies by innovation.
The plethora of new features "are good steps in thisdirection, but they can be seen as gimmicks rather than gamechangers. At this point, Samsung appears to be trying to killthe competition with sheer volume of new features," said JanDawson, chief telecom analyst at IT research outfit Ovum.
"For now, Samsung can likely rely on its vastly superiormarketing budget and the relatively weak efforts of itscompetitors in software to keep it ahead."
The success or failure of Samsung's latest flagship phone -the fourth in a brand launched in 2010 - will be pivotal in theworld's biggest smartphone maker's battle against Apple andsmaller, and key to that struggle will be phone differentiation.
Apple may already be feeling the heat.
Just a day before, marketing chief Phil Schiller blastedSamsung and the Google Android software in rareinterviews given to Reuters and other select media, underscoringthe pressure that the iPhone maker is feeling from its Koreanmobile-phone nemesis.
The S4, which Samsung preceded with a marketing blitz thatdrummed up industry speculation reminiscent of some of Apple'spast launches, will be available by the end of April and rolledout to 327 carriers in 155 countries, including U.S. serviceproviders Verizon Wireless , AT&T Inc,Sprint Nextel, T-Mobile USA.
"Samsung has fulfilled the promise of their marketing thatthey are the tech innovators. It remains to be seen whether it'soverload for customers, whether they can really take advantageof all these features," said Forrester analyst Charles Golvin.
The S4 will use either Samsung's own applications processoror Qualcomm Inc's Snapdragon central processing chip,depending on the country. But the Korean company kept mum onexact dates and prices.
SAMSUNG HITS BROADWAY
Samsung took a slightly different tack with the S4's launch,using actors and a full live orchestra to present thesmartphone's various features via a series of skits - as perhapsbefitted its theatrical platform.
That marked a departure of sorts from the usual slick,high-wattage shows favored by rivals such as Apple.
Investors largely shrugged off the launch. Shares in Samsungwere 2.3 percent lower in a steady market in Seoul on Friday.
The stock has stood little changed so far this year, whileApple's shares have tumbled 20 percent as disappointing sales ofiPhones raised fears that its dominance may be slipping.
Apple's U.S. sales outstripped Samsung's for the first timein the quarter ending in December, even after Samsung spent arecord $400 million on phone advertisements here last year.
While the global smartphone market's growth rate is taperingoff, Samsung still derives the majority of its annual profitsfrom Galaxy phones.
Samsung said the Galaxy S4 will sport a bigger 5-inchdisplay than the S3's 4.8 inches. But because the new displaywill cover more of the phone's surface area, the device itselfwill be the same length and slightly narrower, thinner andlighter than the previous generation.
The newest features involve different options fornavigation. For example, if the phone senses someone is lookingat the screen, the user can tilt it forward or backwards toscroll up and down a Web page.
That feature falls slightly short of what some consumers mayhave expected after the New York Times reported that the phonewould be able to scroll automatically by tracking readers' eyes.
But what it can do is sense when it has someone's attention.When a video is playing, for instance, the stream willautomatically pause if the person glances away and it willrestart when the eyes refocus on the screen.
This is an update on an existing Galaxy feature, whichpowers down the display if it senses no one's looking at it,conserving battery power.
The latest phone also has a sensor that lets users movetheir hands to the left or right to scroll between differentwebsites they have opened or through songs or photos in an albumwithout having to touch the phone.
The idea is to make it easier to change the song playingwithout having to pick up the phone while driving or to avoidputting sticky fingers on the touch-screen display whilescrolling through a Web page at mealtimes.
The phone will also allow users to hover a finger over anemail inbox or a photo gallery to get a glimpse of more detailsof what's in the email or which photos are in an album.
Another feature includes the option to automatically put acopy of details from a photograph of a business card into thephone's contacts database or call a number in the business card.
Samsung is also promising an instant translation between 10different languages for certain applications, as well as aseparate translation application on the device.
The device also has a 13-megapixel camera, compared with theS3's 8-megapixel camera.
"They kind of cherry-picked features that other competitorshad, and then packed them up all together into one device," saidGartner analyst Carolina Milanesi.
"The story though is more about who Samsung is and wherethey want to be. It is clear today that they want to play in anecosystem game, their own ecosystem. The word Android didn'tcome up once."
