The tool will allow users to see whether a business account has been verified by WhatsApp before initiating a conversation. Currently, the feature, which has been downloaded by reporters at CNBC through the Google Play store, is in beta on Android and enables WhatsApp itself to communicate with users.

WhatsApp, which Facebook acquired in 2014, said in a blog post a year ago that it "plans to test ways for people to communicate with businesses in the months ahead." Facebook CEO Mark Zuckerberg said last week that he wants the company's messaging products -- WhatsApp and Messenger -- to speed up their efforts to generate sales.

Zuckerberg needs diversified revenue streams as growth in Facebook's core ad business starts to slow. He told analysts on a conference call following second-quarter results that the company has to "move even faster" on its messaging products.

Secure chat sessions via text, calls or video

Facebook bought WhatsApp for $19 billion, nabbing a service with viral consumer usage but no established business model. Offering users and businesses secure, verified communication channels could be a key to realizing that value.

Eventually, this feature could allow verified businesses another way to provide customer support. And not just by text.

WhatsApp founder Jan Koum said last week its 1.3 billion monthly users share 1 billion videos per day, along with 55 billion messages.