Swirl, which offers a platform for retailers and brands to market to customers via beacons, announced Thursday it has raised $18 million from a handful of investors, including Twitter Ventures.

Other investors in the Series C round include Hearst Ventures and Softbank Capital, both who have funded Swirl in the past.

Beacons are a young, Bluetooth-powered technology that provides the potential for companies to specifically target in-store customers. A retailer could realize that a customer has been dwelling near its TVs for 15 minutes, and send a coupon for a 4K TV via a smartphone push notification.

In one recent success story, American Eagle Outfitters found it could increase the likelihood of a customer trying on clothes when it used beacons to send customers a push notification.

Still, beacons have a ways to go before gaining mainstream adoption. A sticking point has been ensuring customers have the relevant app installed on their smartphone, which acts as a tripwire of sorts and tips off the store of the consumer's location.

If a customer doesn't have the right app, they'll never receive the notification. This is what makes the interest of social networks such as Twitter and Facebook so noteworthy.

"Everybody's got one of these widely distributed apps on their phone," said Swirl chief executive Hilmi Ozguc. "That's where the whole picture is completed, and that's what's exciting about this."

Facebook announced in January it is testing using beacons at eight stores in New York City. Twitter declined to comment on its interest in beacons.

With a treasure trove of information about users, social networks are already well-positioned to target advertisements at an extremely granular level. Facebook and Twitter could potentially take this another step forward, and fine-tune ads for users' exact locations at a given moment. They could likely charge a hefty premium for such ads.

"There's a vast market potential here. And it's going to be a big source of new mobile advertising revenue for a lot of companies," Ozguc said. "From Facebook to Twitter, to you name it. So I think you'll see a lot of these big guys start to make some moves and bets on the space and start offering the benefits they bring, this massive audience reach."

Swirl says it will use the new funding to expand its sales and marketing operation, invest in its products and meet the demands of retailers. Ozguc says that 70 of the top 100 retailers are either Swirl customers, piloting its technology or in talks with his company.