Fashion brands are getting chatty on WhatsApp with the messaging platform’s 1 billion reported users.

Brands like Diesel, Burberry, Clarks, Agent Provocateur and Kenneth Cole have begun testing the space, which attracts global users to data-free messaging groups, for new marketing and customer service initiatives. It’s still early days for brands on WhatsApp — most are approaching it as an experimental platform — but with retailer mobile app traction on the decline and Facebook Messenger still building out its offering to be more brand-friendly, quick adapters of the chat-driven technology could find themselves at an advantage.

“Now is the perfect time for [brands on WhatsApp],” said Renato Mendes, senior product strategist at Huge. “It’s not that early in the sense that it’s not a dark territory, since some brands have already developed some successful ideas, and not too late to be the last one in the party.”

Right now, brands are finding that a WhatsApp strategy makes sense for the always-time-strapped consumer. Instead of asking them to seek out the brand’s mobile app for a personalized experience, brands will come to them to talk where they already are. And since only 20 million of WhatsApp’s 1 billion users are projected to be based in the U.S. in 2017, according to Statista, the app serves as a door to an international audience.

“People are spending 90 percent of their time on mobile in apps, but it’s certainly not in retail apps. It’s the social apps, and people are talking on them, especially internationally,” said Matt Asay, vp of mobile at Adobe. “But the goal shouldn’t be to monopolize my time, it should be to make my time when I am interested in shopping productive.”

India’s 160 million users account for WhatsApp’s biggest market as of November. There, brands are using the space to promote products. Reliance Brands, which retails Diesel, Kenneth Cole and Brooks Brothers in the country, engages customers on the app who don’t have access to physical stores. On WhatsApp, customers can select items they want to be delivered by scrolling through the latest updated stock. A Reliance Brand representative said in 2015 that conversion rate was as high as 80 percent, and that “cash-rich-time-poor” customers appreciated the convenience of the direct conversation.

It helps that that conversation doesn’t cost the brands a lot, either.

“One of the most appealing things about WhatsApp is its success rate,” said Mendes, who cited a study that found 98 percent of WhatsApp messages are opened and read. “Second, it’s cheap. Cheaper than any customer service or advertising on any traditional media, with the bonus of the automatic opt-in, since the customers gave you their telephone numbers.”

Over the holidays, high-end lingerie brand Agent Provocateur set out on WhatsApp with a goal to help couples buy items. The customer service strategy was aimed at the “time-poor” customer, a brand spokesperson told Digiday, and also the retailer’s VIPs, who are becoming increasingly important in a competitive retail market.

WhatsApp’s current advantage: It’s less crowded by other brands than the Facebooks and Snapchats of the world.

“The challenge brands have is finding an uncluttered environment where they can talk to customers,” said David Cooperstein, an advisor to the programmatic platform Pebblepost. “They know people are spending time on WhatsApp, and they’re looking for ways to get visibility.”

WhatsApp’s one-on-one conversations can also funnel important customer insight back to the retailers. Clarks, a British shoe brand, launched a WhatsApp campaign back in 2015, “From Rats to Rudeboys.” The campaign was anchored around three characters telling the product design story of the Clarks desert boot, and WhatsApp users could start a chat conversation with one of the three characters to ask questions and receive updates from the brand. Clarks’ goal was to learn more about the people who were interested in the campaign, and the boot: Each conversation came with a disclaimer telling the person on the other end that their responses would be stored and used by Clarks.

“You can foster a real community with your users, and as a result, obtain more accurate data — more than demographic reports and quantitative researches, you have a channel with data coming directly from your users, which is huge,” said Mendes. “Imagine the possibilities of improvement with it. Brands might use this raw data to work collaboratively with fashion trendsetters, combining creativity with inner desires.”

Outside of WhatsApp, brands have tested conversational-driven customer service and marketing on apps like WeChat, Line and Facebook Messenger, as customers are becoming more open to the idea of chatting with a brand. So far, WhatsApp’s full potential is still yet to be tapped. For fashion, specifically, Mendes envisioned upcoming use cases that included customer service–driven outfit advice that shared brand-approved opinions for those who opted in. Fashion publishers like British Vogue have begun testing in the space, as well.

“It’s a bold, but expected and needed move,” he said. “Traditional narratives and advertising are not sufficient anymore.”