Does the future of media include breaking-news headlines materializing in front of your eyes as you walk down the street?

CNN and Elle magazine have become the second and third media brands with apps on Google Glass, following The New York Times, and all three are testing early adopters' appetite for a constant stream of content served to them on the go. In their current form, the apps seem to follow the vein of push notifications mobile phone users get increasingly frequently from The Times and The Wall Street Journal. Unlike the apps those push notifications bring users to, however, the media brands' Glass apps aren't allowed to carry ads.

The revenue opportunity is currently minuscule in any case. Google Glass is still only available to a small group of people -- mainly developers -- who plunked down $1,500 for the privilege of beta-testing the device.

CNN, part of Time Warner's Turner division, and Elle, part of Hearst, joined companies with a lot more engineering firepower at their fingertips -- Facebook, Twitter, Tumblr and Evernote -- in introducing "Glassware," the name Google has given to Glass apps, at the I/O developer conference in San Francisco yesterday.

While the prospect of being early to a new market and collecting feedback from early adopters is compelling, there's more to it than that, according to Barin Nahvi, a member of Hearst's corporate technology team and project manager for the Elle app. Building "Glassware" could potentially help Hearst get smarter about designing experiences for mobile in general, she said.

"[Glass is] an extreme version of a lot of the principles you need to be thinking about with mobile apps," she said.

Elle is offering four subscriptions on Glass: horoscopes; a "dispatch" of posts with an emphasis on snappy headlines, parties and celebrities; street fashion; and a "lookbook" where users can watch an image of Suri Cruise materialize and then tap their Glass to open a gallery and scroll through more of the famous tot's couture.

Posts are light on text and heavy on images, though subscribers have the option to have an excerpt of an article read aloud to them and save it to read in full later. Users will get 8 to 10 updates per day at most, Ms. Nahvi said.

CNN, on the other hand, will deliver updates from a menu that includes breaking news, on the order of 18 headlines per day, as well as tech, politics and business. Subscribers can read short news briefings on the lens or have them read aloud and watch accompanying video clips.

In a demonstration, this reporter saw an update about an Internet-celebrity hitchhiker being sought as a murder suspect in New Jersey, but struggled to make out any of the audio. Having a lot of hair can apparently interfere with the speaker on Google Glass.

Jeff Eddings, who led the CNN app in his role as senior director of emerging technology at Turner, said that possible applications of Google Glass for a news-gathering organization go well beyond breaking news updates. If the hardware is adopted at scale, it could become a useful way for people to submit photos and video from the scene of a major news event like the Boston Marathon bombings, he said. That method of submission might also have the advantage of baked-in location data, giving the news organization more confidence that the footage was shot where the sender claims.

And while there are no ads allowed in "Glassware" yet, that could obviously change as the platform matures. "I think in the future, [Google is] thinking about how to help app developers and publishers monetize this," Mr. Eddings said.