Your Phone’s Secret Life: What We Uncovered About 5 Viral Surveillance Myths

While these innovations offer convenience, they often come with a hidden cost: privacy.

The Federal Trade Commission warns that companies can now track online activities whenever users interact with internet-connected devices. Websites may use cookies to track someone even after they leave the site. Some apps allow advertisers to use a unique identifier to track a person’s activity, and companies may be able to track activity on different devices, including phones and laptops, as long as they’re connected to the internet. Online sources can amass details on everything from purchase history and social media activity to magazine subscriptions and even political affiliations.

Data brokers collect this information from online sources, sometimes without a user’s knowledge. The FTC reports that this info can include purchase history, social media activity, magazine subscriptions, and even political affiliations. User profiles are then sold to businesses that target potential customers with eerily specific ads.

Experian, one of the largest data brokers in the United States, uses data about hundreds of millions of people’s locations, demographics, purchasing habits, lifestyles, and interests to help marketers “gain granular insights into who your customers really are.”

So it’s no wonder some people believe their phones are “listening” to them—even if that’s not exactly the case.

“When most people see unexpected ads, it’s because they’ve been targeted based on huge lists of private information about them that was collected in other covert ways,” an Electronic Frontier Foundation report found.