Screenshot by Lance Whitney/CNET

Samsung's Galaxy S6 will go the curved display route, based on a promo image on posted by US carrier T-Mobile's website.

A sign-up page for the carrier flashes an image of a Samsung phone with the tag line "Six Appeal," almost certainly touting the Galaxy S6, which expected to be unveiled on March 1 at Mobile World Congress.

The image shows only one side of the phone, but it clearly sports a curved edge, borrowing a feature from Samsung's Galaxy Note Edge . Wrapping around one side of the phone, the curved edge displays icons, notifications and other content.

Samsung's current flagship phone, the Galaxy S5, was dinged for being too similar to its S4 predecessor. The company's sales and market share have fallen in the face of competition on the low end from Chinese vendors such as Xiaomi and on the high end from Apple, with its big-screened iPhone 6 lineup. As such, Samsung desperately needs a hit with the Galaxy S6, and that means the phone needs some killer feature to lure in customers.

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Previous reports have suggested that one killer feature could be a curved display. If so, just how far will Samsung go with that? Some reports have said the Galaxy S6 would sport just one curved edge, similar to the Galaxy Note Edge. Other reports say the S6 would offer curved edges on both the right and left sides, giving the phone three sides of screen real estate. Another possibility is that Samsung will launch two different S6 models -- one with the standard front-facing display and a second with the three-sided display.

Samsung has also been busy teasing the Galaxy S6. A video entitled "Samsung Galaxy Unpacked 2015 -- The Next Galaxy" plays up the metal aspect of its next phone. The Galaxy S lineup has traditionally offered a plastic body, which Samsung has defended as a good thing. But the plastic does make the phone feel cheaper in comparison to an iPhone 6 and other rival phones. The new teaser all but confirms recent reports that the S6 will sport a metal back.

Whatever features we discover in the Galaxy S6, mobile carriers are apparently jazzed about the new phone, according to a story published Sunday by the Korea Herald. Samsung reportedly showed off both the S6 and the new Edge smartphones to executives from the US's T-Mobile, Sprint, Vodafone and Korea's SK Telecom, and those folks were said to be impressed with the style of both.

"Some executives said the new phones were the best of the best among Samsung-made phones," a source close to the matter told the Korea Herald.

The new Edge especially earned kudos, according to the story, as it will feature a curved display on both sides. The executives even said the new Edge surpassed the iPhone 6 in design. Assuming the source is accurate, the report could indicate that the Galaxy S6 will go with one curved edge, while the new Galaxy Edge will take on two curved sides.

However, other sources claimed the meetings with the carrier executives were simply regular ones in which all the parties involved talk about the release schedule and marketing plans for new phones. Either way, we'll get a chance on March 1 to see if the new Galaxy S6 and Edge phones have the right stuff to battle back against the competition.

A Samsung spokeswoman declined CNET's request for comment.