LONDON (CBS) - Many people believe social media companies are spying on our conversations and targeting ads based on what we say out loud. But is it really happening?
A British security company is trying to get to the bottom of it.
Yvette Shapiro was recently on a family vacation in Virginia.
“I said to my husband, our phone is listening to us,” Shapiro said.
They were discussing how comfortable their mattress was. Shapiro says soon after, ads for mattresses appeared on her Facebook feed.
“I find that a little invasive, a bit creepy and certainly unwelcome,” she said.
You can find plenty of similar claims online:
Facebook CEO Mark Zuckerberg shot down the suggestion when he testified before Congress last year.
“Yes or no - does Facebook use audio obtained from mobile devices to enrich personal information about its users,” asked Sen. Gary Peters.
“No,” responded Zuckerberg.
To find out who's right, a security company in London put our phones to the test.
“We don't believe that they are spying,” Wandera CEO Eldar Tuvey said.
London firm Wandera did a three-day experiment. They played pet food commercials for 30 minutes with a smartphone in the room.
They left another cell phone in a silent room next door.
“We weren't able to discern any kind of noticeable difference in terms of the adverts that were being received by that phone versus the other adverts from the phone that was in the silent room,” Tuvey said.
Instead, the firm's CEO believes our online activity reveals more to tech giants than we realize.
“The advertising algorithms can figure out exactly through the searches that we do, what we're interested in, and then they target those adverts to us,” Tuvey said.
But people like Shapiro are still not convinced.
“I don’t see why they wouldn’t be doing this because it’s such an obvious moneymaker,” she said.
Whether suspicion or fact, it's unlikely to keep most people off their smartphones.
Researchers at Northeastern University in Boston studied 17,000 Android apps last year. They found there was no evidence of conversations being spied on, but a handful of apps were taking screenshots of what people were doing.