SAMSUNG on Wednesday unveiled a smartphone that folds open to be a tablet, becoming the first major manufacturer to offer the feature as it strives to stoke excitement in a slumping market.

The South Korean giant also appeared to get the jump on rivals by announcing the first smartphone for fifth-generation (5G) wireless networks, while stepping up its efforts in artificial intelligence and wearables.

The Galaxy Fold, unveiled at a San Francisco event, serves as a smartphone with a 4.6-inch display and opens like a book to become a 7.3-inch tablet.

“We are giving you a device that doesn’t just define a new category, it defies category,” said Samsung’s Justin Denison at the event.

The Fold will be available April 26 starting at $1,980, the company said.

The launch comes as the smartphone market experiences its worst-ever decline with consumers keeping devices longer and waiting for new innovations.

Samsung made the announcement on the home turf of rival Apple, with the two giants battling in the premium segment of the market.

Denison touted the Fold as “a one of a kind luxury device” and boasted that it lets three apps operate simultaneously on its large screen.

“You can watch a YouTube video of Hawaii – text your friend about it, and browse travel options all at the same time,” Denison said while showing off the device.

Samsung also announced new Galaxy S10 models, upgrading its current line of flagship handsets to include a 5G device.

Rivals are expected to make 5G smartphone announcements at next week’s Mobile World Congress.

“We are pushing beyond the limits of today’s technology to inspire a new generation of smartphones and recharge growth for our industry,” said DJ Koh, head of mobile communications at Samsung Electronics.

“For those who say everything possible has already been done, I say open your mind and get ready for the dawn of a new mobile era. Buckle your seatbelt, the future is about to begin.”

He said the Galaxy Fold was designed “for those that want to experience what a premium foldable device can do, beyond the limitations of a traditional smartphone”.

Technalysis Research analyst Bob O’Donnell said on Twitter: “As expected, it’s not cheap, but the #GalaxyFold will still be THE device for gadget lovers.”

The S10 handsets, coming in four versions, will offer rich colour displays, longer battery life and sophisticated cameras.

They will feature AI-enhanced software and wireless charging capabilities that allow Galaxy smartphones to be used as charging pads to power up other devices.

No price or release date was announced for the S10 5G version. Other options include the S10e starting at $749, and the largest version, the S10 Plus, at $999 – which will be available on March 8.