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* S4 boasts 5 inch screen, 13 megapixel camera
* Adds browser scrolling by tilting the phone
* Offers hand gesture navigation between Web pages
By Sinead Carew
NEW YORK, March 14 (Reuters) - Samsung Electronics Co on Thursday premiered its latest flagship phone, theGalaxy S4, which sports a bigger display and unconventionalfeatures such as gesture controls and will spearhead its effortto challenge Apple Inc on its home turf.
The phone is the first in Samsung's highly successful GalaxyS-series to make its global debut on U.S. soil, and representsanother bet that consumers prefer larger screens.
The S4 - which Samsung preceded with a marketing blitz thatdrummed up industry speculation reminiscent of some of Apple'spast launches - will be available globally in the secondquarter. Samsung said all major U.S. service providers will sellthe phone but it kept mum on exact dates and prices.
The company was more than willing to share some of thelatest Galaxy phone's capabilities: it can stop and start videosdepending on whether someone is looking at the screen, flipbetween songs and photos at the wave of a hand, and otherfeatures not typically found on rivals' screens.
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 rivals to attract consumers who have a dizzying array ofchoices in advanced phones.
Samsung held the global launch event in the United States inthe hope of regaining the lead in the crucial market. Apple'sU.S. sales outstripped Samsung's for the first time in thequarter ending in December, even after Samsung spent a record$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 S III feature whichallows the screen to sense whether or not the user is lookingat. If there is nobody looking at the S III, the screen's lightswitches off automatically to conserve 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 theS 3's 8-megapixel. U.S. operators planning to sell the S4include Verizon Wireless , AT&T Inc, SprintNextel, T-Mobile USA and smaller operator LeapWireless.
