People clearly aren't ecstatic about the idea.

Christine is a journalist from South Africa, who has lived and worked in Europe, Africa and the Middle East, covering everything from hard news to art to business & tech. Having been bitten by the travel bug as an infant, Christine finds it fairly easy to uproot herself in search of new adventures and stories. With degrees in both fine arts and journalism, she’s equally interested in visual storytelling as well as the written word. Having been part of three launch teams of three different media startups in her lifetime, she’s intimately familiar with what it takes to get a publication off the ground.

Last week the world’s favourite messaging service, WhatsApp controversially announced that it would start sharing some user data, including phone numbers, with its parent company, Facebook.

All in the name of targeted advertising on the giant social network, it means that WhatsApp users could soon start seeing ads and Facebook friend suggestions that could seem a little too close to home.

The news has been met with outrage and a hasty scuffle to “disagree” with the terms and conditions. It has also sparked questions as to where the line is with regards to invasive advertising, and added to the wider debate surrounding ad blockers, and free access to content.

Nothing comes for free. Which means that continued use of social networks and other content sites would mean a compromise between user and business.

Facebook Inc. has been looking for ways to monetize WhatsApp since it bought the service two years ago, but at the same time, has also pledged not to interfere with a longstanding promise by WhatsApp’s co-founders to respect users’ privacy and keep ads off its messaging platform.

The two companies say the new policy would help users easily find friends and “improve Facebook ads and products experiences.”

However it’s also set to open up a whole new avenue to businesses wanting to reach potential customers.

WhatsApp described situations where banks and airlines could even use your phone number to get in touch about fraudulent payments or delayed flights.

Although, shouldn’t banks and airlines you’re registered with already have your number on file? Who decides which companies are worthy to receive your number?

WhatsApp has promised that it won’t sell or share that number with advertisers, but seeing as the trust factor for advertising is relatively low, there are many that flinch at the idea of putting their contact details where a legion of hungry brands could potentially see it.

“This is a strong-arm tactic on the part of Facebook,” Jeff Chester, executive director of the Center for Digital Democracy in Washington, D.C. was reported as saying “They continue on a campaign to run roughshod on our privacy rights.”

In the past privacy groups have praised WhatsApp for building powerful encryption into its services, making it impossible for the company or anyone else to read users’ messages. WhatsApp promises that encryption will remain, so neither WhatsApp nor Facebook would be able to use message content for advertising purposes.

But privacy activists also criticized the 30-day window to opt out.

“Very few people opt out, it should be an informed opt in,” Chester said. “No data should be used unless people are informed honestly about how it’s going to be used.”

How to opt-out

You can stop WhatsApp from handing over your data to Facebook. If you haven’t yet, you should receive a popup screen with new terms and conditions. Rather than clicking “agree” press the smaller “read more” option below, and uncheck the box that reads “Share my WhatsApp account information with Facebook…”

If you’re like the vast majority of the population and don’t read the T’s & C’s before blindly clicking “Agree” then chances are you’ve already consented to the new policy. However all is not lost, there is still a way to undo this – but you have less than a month, so do it sooner rather than later.

Head to the app’s settings menu, and then press the account tab. From there, you can uncheck the box reading “Share my account info” to stop providing Facebook with your user data.