Discussed that one Christmas gift and immediately an advertisement appeared on your smartphone: how is that possible?

You’ve only talked about a present you would like under the Christmas tree, and suddenly an advertisement pops up in your web browser or on social media. There’s no way your smartphone is listening in on you, right? The reality turns out to be different, but not therefore more reassuring.

Don’t worry, dear reader: neither Mark Zuckerberg nor his staff at Facebook or parent company Meta spends their days eavesdropping on you and your family. Not because they could not, but because tech giants such as Google, Amazon, Apple and Meta – also owners of Instagram and WhatsApp, among others – do not benefit from this. “It would simply be a very inefficient way to collect information about us, which would also increase our data consumption and quickly drain our battery,” says Flemish computer scientist Jeroen Baert.

Legally, smartphone or app developers would also be trespassing. After all, eavesdropping on someone to deliver targeted advertisements is a violation of privacy.

‘Look after’

“We are actually not aware of apps that are eavesdropping on us,” says Steven Latré, computer science professor at the University of Antwerp and head of Artificial Intelligence at IMEC. “In the case of large companies and well-known apps, you can rule out this happening, even if you grant those apps access to your microphone. With smaller, unknown apps, it’s best to be very careful about what permissions you give them. If an app requests access to your microphone when it is not actually necessary, it is better to refuse it. And if your microphone is active, a light will light up in a corner of your screen as a check.”

Scientists have already conducted experiments several times in which they expose new smartphones in an ‘audio room’ for a long time and repeatedly to conversations about certain products, while in another, quiet room the same type of telephone receives no input. This never led to more advertisements of the promoted products on devices in the audio room, and data consumption in the audio room did not increase, while you would expect it to.

Cookies

Yet many readers will recognize themselves in the situation: just talking about that trip to Spain, and an advertisement for a week in Costa Brava suddenly appears in our browsers and apps. How do they know that?

The explanation is sometimes relatively simple: for example, you and your husband use the same Wi-Fi network and perhaps your wife accepted cookies during her search for gifts, so that other users of that network also see advertisements for a product she has been looking for.

Online footsteps

The reality is that tech giants follow us on multiple devices at the same time and know our age, place of residence, relationship status, gender, education level, interests, surfing, consumption and clicking behavior and constantly know where and with whom you hang out. Throw all that data into one big pot, pour it into an algorithm, and the uncomfortable truth is that your behavior also becomes depressingly predictable.

How exactly these algorithms work is a mystery even to experts, but they are becoming more advanced every day. Advertisements are becoming (even) more personalized, driven by artificial intelligence, which has also made its debut in the advertising world. So don’t be surprised if you, as an avid athlete, are advertised for headphones on a runner’s head, while your friend, an avid commuter, is advertised with the same headphones as the key to a peaceful train ride.

Delete cookies

Such developments may feel uncomfortable, which is why it is important that we are aware of our rights. “Don’t just accept all cookies all the time,” advises Professor Latré, who advocates basic hygiene on the internet. “Consent is given in one click, but very few people withdraw it. Therefore, go through your smartphone from time to time and check what apps are allowed to know about you. Ask yourself whether all those apps should always have access to your location or microphone.”

How do you do that? On an Android phone, go to ‘Settings’ and click ‘Apps’. You can then go to ‘Authorization management’ via the three dots in the top right corner. You can then see which apps have access to your microphone under ‘Microphone’ and adjust your preferences. Also on an iPhone, open ‘Settings’, but then tap ‘Privacy’ and then ‘Microphone’. You will then see the apps appear in a list and you can adjust your preferences via a green switch.

This article previously appeared in an adapted form at Het Nieuwsblad.

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