Do advertisers eavesdrop on the conversations you have around your phone?

You mention to a friend that you’re thinking about buying a coffee machine. A few hours later, you open Instagram and find yourself staring at an advert for the exact thing you were discussing. Naturally, you start wondering whether your phone is listening to your conversations.

It is probably not. But what it actually does isn’t necessarily less creepy.

Is your phone actually listening to you?

Technically, yes, under certain circumstances. If you’ve enabled Siri or Google Assistant’s voice activation, your phone needs to recognise phrases like ‘Hey Siri’ or ‘Hey Google’. This means it’s continually checking for those specific sounds.

However, recognising a wake word isn’t the same as secretly recording your conversations. Voice assistants generally process wake-word detection on your device. Once activated, they may send audio to external servers to process your request, depending on the assistant and its settings.

Accidental activations can happen, too. We’ve all had Siri interrupt a perfectly normal conversation with an answer nobody asked for. But there’s no convincing evidence that major advertising platforms routinely use your phone’s microphone to record private conversations for targeted advertising.

Then how does my phone know what I’ve been talking about?

Advertising platforms already have access to an enormous amount of information about your online behaviour, depending on your privacy settings and the permissions you’ve granted.

They can use signals such as browsing history, social media activity, location and shopping habits.

All of this can help advertisers predict what you’re likely to buy, sometimes before you’ve seriously considered buying it. And here’s another possibility: you might not have searched for something yourself, but someone in your household has. Shared interests, location signals and similar browsing patterns can lead to overlapping adverts.

None of this requires access to your microphone.

But what if I’ve ONLY talked about something?

Think about how many random subjects you discuss throughout the day. Most of them never appear in your adverts, and you don’t give them another thought. But when you mention needing a new mattress and suddenly see an advert for one, you remember it. Your brain connects the conversation to the advert because the coincidence feels significant.

Of course, that doesn’t mean every suspiciously accurate advert is a coincidence. Tracking and profiling are real, and advertising companies can make surprisingly accurate predictions from fairly limited information.

It’s just that a well-timed advert isn’t proof that your phone was listening.

How to check whether your phone is using its microphone?

Both iPhones and Android phones have built-in privacy features that show when apps access your microphone.

On an iPhone: open Settings > Privacy & Security > Microphone. Then check which apps have permission to use it and disable access for anything that doesn’t need it.

An orange indicator at the top of your screen means your microphone is being used. A green indicator means your camera is being used, potentially alongside the microphone.

You can also visit Settings > Privacy & Security > Tracking to restrict apps from tracking your activity across other companies’ apps and websites.

On an Android phone: open Settings > Security & Privacy (the wording varies by manufacturer). Find Privacy Dashboard and select Microphone to see which apps have accessed it, then review or revoke any unnecessary permissions.

On modern Android phones, a green privacy indicator also appears when your microphone or camera is in use.

Can you stop your phone from showing personalised adverts?

You can certainly reduce them. For starters, review your advertising privacy settings. Google’s My Ad Centre lets you control whether your Google account activity is used to personalise adverts.

You can also reject optional advertising cookies, limit app tracking and disable voice activation if you don’t use it.

Bear in mind that switching off personalised advertising won’t eliminate adverts altogether. It simply restricts some of the information advertisers can use to decide which ones to show you.

So, is your phone spying on you?

There’s an important difference between your phone listening for a voice command and advertisers building a profile of your interests. The first is a feature you can control. The second is an entire industry built around understanding consumer behaviour.

Your phone probably isn’t secretly recording your dinner conversations to sell you a new coffee machine. It doesn’t need to. You’ve already left plenty of clues about yourself online. Advertisers are just rather good at putting them together.

And somehow, that doesn’t sound particularly reassuring either, does it?