Despite what you might have heard, your smartphone probably isn't recording your conversations so it can target adds at you. It may, however, be sending sending screenshots out to third parties.
Researchers at Northeastern University in Boston evaluated 17,260 Android apps over the span of year to determine whether or not any of them could silently send voice recordings to third parties without your express permission. But, they didn't find an evidence to suggest that was happening.
"We didn’t see any evidence that people’s conversations are being recorded secretly," said David Choffnes, one of the study's authors told Gizmodo.
Of course, there are plenty of other ways your phone may be spying on you that the researches say they didn't examine. For instance, the phones were in a controlled environment and not being used out in the real world, where they might face other 'spy' triggers. It's also possible that conversations could be transcribed before being sent out.
They did definitively determine that smartphones do spy on some people though. Some of the apps they tested were observed taking screen captures or even video, and sending them over out to the app's database. This didn't happen with all the apps the researches tested, but it's an unsettling finding nonetheless.
The finalized report is set to be presented in Spain next month. Hopefully their findings will lead to improved privacy policies for consumers.