A mobile security company has carried out a research investigation to address the popular conspiracy theory that tech giants are listening to conversations.

The internet is awash with posts and videos on social media where people claim to have proof that the likes of Facebook and Google are spying on users in order to serve hyper-targeted adverts.

Videos have gone viral in recent months showing people talking about products and then ads for those exact items appear online.

Now, cyber security-specialists at Wandera have emulated the online experiments and found no evidence that phones or apps were secretly listening.

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