Andrew Hoyle/CNET

Samsung just launched its Galaxy S9 and S9 Plus, but mobile CEO DJ Koh dropped a few bread crumbs of a trail to what's to come.

While Koh was mum on details about the company's foldable phone project, he said in an interview with CNET on the sidelines of the launch event that the company is making progress on the device, rumored to be called the Galaxy X. But he's focused on ensuring that this isn't just a gimmick.

"I need complete confidence that we're delivering the best user experience when we're launching a new category," Koh said.

When the time comes to show off the device, Koh said he'll be open about the new product.

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But when asked whether he can say whether the foldable phone would launch this year, he responded with a sly smile, "Sometimes I do not listen. My ear is not so good."

It's getting more and more difficult for handset makers to make huge design changes in their devices. Instead, most of the changes are coming through software and services updates or new technology under the hood, like the S9's improved camera. A foldable phone would be a huge leap in device design. While it's unlikely to be the device most consumers would opt for, it could get people excited about phones again.

The smartphone market has been slowing down of late. Sales actually fell for the first time ever in the fourth quarter, according to Gartner. It's become harder for handset vendors to make huge changes in their devices and differentiate from one another. Prices for the latest and greatest phones have actually increased at the same time US carriers have gotten rid of subsidies. All of that's meant people are waiting longer to upgrade.

Samsung in 2016 filed a patent for a phone that folds in half, and late last year, Koh said the company would launch such a phone once it resolved "some problems."

Samsung said during its latest earnings report at the end of January that it "will continue its efforts to differentiate its smartphones by adopting cutting-edge technologies, such as foldable OLED displays."

Bixby speaker coming

Koh also confirmed that a smart speaker powered by its own voice assistant, Bixby, would come later in the year.

He earlier told The Wall Street Journal that the speaker would launch in the second half of the year.

When pressed for a more specific launch window, he said he couldn't guarantee a date yet. "Give me more time," he said.

Bixby is Samsung's homegrown digital voice assistant that launched with last year's Galaxy S8. It initially was geared as an interface to control the phone, but Samsung since has been working on expanding the technology into its various appliances and televisions. Bixby will show up in Samsung's TVs this year, as well as its Family Hub refrigerator.

Putting Bixby in a smart speaker is the next logical move for the company, which bought Harman and its well-regarded audio business last year. Smart assistants are seen as the future of how we'll interact with our gadgets.

But Samsung and Bixby face an already crowded market. Amazon with its Alexa-enabled Echo speakers, virtually dominates the smart speaker market, while Apple with its Siri-controlled HomePod is trying to appeal to higher-end audiophiles. Google, the provider of the operating system that runs on Samsung's phones, also has been pushing its Assistant in speakers and other devices.

Samsung earlier was expected to launch is Bixby speaker in the first half of 2018. A Journal report now pegs the introduction for the second half of the year.

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