Samsung Galaxy S6: What to Expect From the Big Reveal

— -- Samsung has dropped some big hints leading up to what is widely expected to be the unveiling of a new Galaxy S6 smartphone on Sunday at the Mobile World Congress in Barcelona.

A photo posted to Instagram over the weekend hinted that the flagship smartphone may come with an all-metal frame instead of a plastic backing like the Galaxy S5.

A video teaser posted to YouTube also drops a big bread crumb when the narrator cryptically says "borders will disappear."

The future smartphone and has been widely expected to take on the curved design that Samsung unveiled with the Galaxy Note Edge. T-Mobile CEO John Legere tweeted also upped the intrigue on Sunday when he tweeted a link to the carrier's website showing off another view of what Samsung is touting as "the next big thing."

Labeled "Six Appeal," the photo shows the profile of a smartphone and that buzzed about curved edge.

Other clues for what to expect from Samsung can be found in the company's recent technological advancements and acquisitions.

The Korean electronics company announced last week it is buying mobile payments start-up LoopPay. In its current form, LoopPay is available as a phone case or a key fob. However, the acquisition sparks the possibility that the technology could be integrated into one of Samsung's future smartphones. Whether that could be the Galaxy S6 or a future phone remains to be seen.

A blog post by Seho Park, Samsung's principal engineer, has led to speculation the new Galaxy S6 could include multiple wireless charging standards, allowing users to juice up their devices almost anywhere.

With a new chip released last year to support multiple charging standards, Park said he expects 2015 will be a game-changing year for wireless smartphone charging.

"Samsung will accelerate to democratize this wireless charging technology with compelling smartphones. With our upcoming Galaxy smartphones, users will be able to enter a new wireless world like never before," Park wrote.

"Two or three years ago, wireless charging was only twenty to thirty percent as fast as wired charging. But since then, we have been able to double the charging speed."

Around the time of Park's blog post, @SamsungMobile tweeted that users can expect something even faster. "I discover more when I make fewer stops. I am #TheNextGalaxy," it said.