Among other things, the changes will affect the ways users can communicate with businesses while continuing to avoid third-party banner ads or spam messages, according to the company.
However, WhatsApp will begin to share some personal details about its 1 billion users -- such as phone numbers and other data -- with Facebook, its parent company. The information sharing will permit better tracking of basic metrics, allowing Facebook to offer better friend suggestions, for example -- and of course, to show more relevant ads.
The increased connectivity and information sharing might not be apparent to WhatsApp users initially. Further, neither WhatsApp nor Facebook actually will read any messages, which are encrypted. Phone numbers and other personal data won't be shared with advertisers.
Despite those limitations, the fact that WhatsApp will share any relevant information with Facebook has raised some flags.
"This announcement should be very concerning to WhatsApp users, who have been promised many times by both WhatsApp and Facebook that their privacy will be respected and protected," said Claire T. Gartland, consumer protection counsel at the Electronic Privacy Information Center.
"That is why many individuals use WhatsApp in the first place," she told the E-Commerce Times.
"WhatsApp may claim otherwise, but this is really the beginning of the end of privacy through that service," warned Jim Purtilo, associate professor in the computer science department at the University of Maryland.
"We've seen this cycle before. Web users visiting sites with a browser once had some sense of privacy, but it didn't take servers long to figure out how to share traffic data with one another and piece together profiles of each user," he told the E-Commerce Times.
"Today, any time you visit a site which offers a Facebook login or an AddThis tag, you also transmit a trace of your activity to big corporations to analyze and use," Purtilo added. "Just browsing is enough -- traffic analysis lets companies fill in the blanks, and this paints a pretty rich picture of you. You'd be pretty naive to think they go to this trouble for your benefit."
The warnings over privacy concerns actually go back to 2014 when Facebook first acquired WhatsApp for approximately US$19.3 billion.
"Jessica Rich, director of the FTC's Consumer Protection Bureau, sent a letter to the companies during Facebook's acquisition of WhatsApp warning the companies that the privacy promises made to WhatsApp users must be respected," recalled EPIC's Gartland.
"WhatsApp's blog describes two different means of opting out of the proposed new sharing," she noted, "and neither of these options appear consistent with Rich's letter, which requires Facebook to get users' affirmative consent before changing the way they use data collected via WhatsApp."
Moreover, it does not appear as if WhatsApp even plans to secure what could be considered "meaningful, informed opt-in consent from its users to begin sharing this information with Facebook," Gartland suggested.
Users will be able to opt out, according to WhatsApp, but it likely will require reading the fine print -- something few users actually do.
"WhatsApp says in a FAQ that existing users can opt out of sharing account information with Facebook for use by Facebook to improve the user's 'Facebook ads and predicts experiences' in two ways," said Karl Hochkammer, leader of the Honigman Law Firm's information and technology transactions practice group.
This method of opting out, in essence, could result in a user's private information still being shared with Facebook.
"All WhatsApp has effectively said is that they are ready to apply the same analysis techniques to messaging as had previously been done for Web browsing," remarked Purtilo.
"Privacy goes out the window at that point, even if bit by bit," he added. "You can't monetize such services without knowing how to tailor your advertising, and the only way to tailor it is by opening up the traffic and content for analysis, so that big corporations will have an even richer picture of you."
It could be that WhatsApp can't afford to disregard the wishes of an installed base of more than 1 billion users, but it's questionable whether many of those users actually care about the new policies.
"On one level, this was probably inevitable. Facebook is a public company that faces investor scrutiny to make a profit," observed Greg Sterling, vice president of strategy and insight at the Local Search Association.
"It is the logic of the market, and thus was unlikely that WhatsApp could continue with the small subscription model," he told the E-Commerce Times. "It simply has too large a user base for Facebook to ignore from the advertiser point of view."
Though there may be a loud and vocal minority that objects, most users will accept the changes.
"Look at the many changes that Facebook has made over the years," said Sterling.
"That hasn't had a detrimental impact on the company, even as many of its users are distrustful of Facebook," he pointed out.
WhatsApp "is probably betting that users who would never try their service under these terms are now sufficiently dependent that they give up their data rather than invest the effort to find alternate products," said Purtilo, "and we've seen that before as well. This is how privacy dies, bit by bit."