The number of WhatsApp users continues to increase, but it does not generate revenue ... yet.

More than a billion people send secure texts and images to their friends, family members and colleagues around the globe for free. The app is accessed via an Internet provider using Android and iPhones, Mac or Windows PC and Windows Phone.

Facebook (FB) acquired WhatsApp in February 2014 for $4 billion in cash and $12 billion in stock. It was founded by Brian Acton and Jan Koum when they worked together at Yahoo. The founders were eligible for an additional $3 billion in restricted stock; the total acquisition price was $21.8 billion.

Experts have surmised that if it added services like its competitors, billions of dollars could easily be generated.

WhatsApp's competitors include messaging apps WeChat and Line, which generate revenue through games, ads, online payment services and in-app purchases.

In 2013, WhatsApp reported only $10.2 million in revenue, according to a filing with the Securities and Exchange Commission. Some users were charged $1 a year to use the app. It spent $149 million in 2013 to generate the $10 million in revenue, so its net loss was $138 million.

While WhatsApp is not generating revenue for Facebook currently, since it lacks a subscription model, Matt Idema, WhatsApp's chief operating officer, told the Wall Street Journal on Sept. 5, 2017, "we do intend on charging businesses in the future."

No further details were provided on what the paid features would include, when the fee would be charged or how much it would cost. Idema told the Journal, "we don't have the details of monetization figured out."

Social networker Facebook began showing ads inside its Messenger app last July to further monetize the chat service. While revenue from Messenger is likely to be generated during the next five years, monetization of WhatsApp's 1.2 billion daily users remains in the future, Facebook executives said last July during the company's second quarterly conference call with investors.

CEO Mark Zuckerberg said on the call that the company needs to speed up monetizing its messaging apps.

"I want to see us move a little faster here, but I'm confident we're going to get this right," he said.

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COO Sheryl Sandberg reiterated the same sentiment and said during the call, "it's early days this year and it's going to continue to be early days for awhile."

Trefis, a Boston-based analytical firm that helps people understand how a company's products impact its stock price, said in a 2017 blog post that the company could generate from $5 billion to more than $15 billion in the "coming" years if Facebook "can implement effective monetization strategies."

WhatsApp was testing a new product called "red envelope," a peer-to-peer payment service, Trefis wrote.

"Reports also suggest that the company is introducing a peer-to-peer payments system on its WhatsApp platform in India, indicating that it is exploring the payments business seriously. The company could also look to monetize WhatsApp by integrating it with Facebook Marketplace," said the blog post.

The company started offering WhatsApp Business on Jan. 18, 2018, which is only available for Android users currently, but remains a free app. Small business can utilize it to interact with clients and the app gives them the ability to automate and sort the messages.

The business component allows companies to create business profiles, messaging tools, messaging statistics and WhatsApp Web. Customers will also be able to distinguish the difference between talking to a person and a business because these profiles will be listed as a business account. In the future, businesses will become "Confirmed Accounts" after being verified that the account phone number matches the business phone number.

More than 80% of small businesses in India and Brazil said the company helps them communicate with customers and grow their business, according to a Morning Consult study, WhatsApp wrote in a blog post.

WhatsApp Business is available to download on Google Play in Indonesia, Italy, Mexico, U.K. and U.S currently.

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