Guide
Is my phone listening to me?
You mention a trip to Lisbon over dinner, and the next morning your phone shows you hotels in Lisbon. It feels like proof that the phone was listening. The evidence points somewhere less dramatic, and in one way more uncomfortable.
In short. There is no good evidence that phones secretly record conversations to choose ads. A 2018 study of 17,260 Android apps found none sending audio in its tests, but it did find apps sending screenshots and recordings of the screen to other companies without telling users. In May 2026 the US Federal Trade Commission charged that a marketing service sold as listening to conversations through smart devices did not use voice data at all: it resold email lists. Your phone shows you when the microphone is on, and you can take the permission away.
The study that went looking
In 2018 researchers from Northeastern University and the University of California, Santa Barbara tested 17,260 Android apps from Google Play and three Chinese app stores. They read the apps’ code for anything that could record, then ran the apps with an automated tester, up to 5,000 taps and swipes each, and pulled every picture, video and sound file out of what the apps sent over the network. They found no app sending audio in their tests.
What it found instead
A food delivery app, GoPuff, began recording the screen as soon as it opened and sent the video to Appsee, an analytics company; in the researchers’ test, the recording exposed the user’s ZIP code. Of the 33 apps in the study that used Appsee, only five marked any part of the screen as private. Some third-party code recorded screenshots and videos of the screen without telling the user and without asking for any permission. After the researchers told GoPuff, it removed Appsee from its apps and updated its privacy policy.
What the study could not rule out
The authors list their limits. Audio turned into text before sending would not show up as a sound file. Apps working together, or media hidden or encrypted inside an app, could slip past them. Automated tapping may not trigger everything a person would. And it was Android, in 2018. A careful study that finds nothing is good news, not proof that nothing happens.
The firm that said it could listen
Cox Media Group, a US media company, and two smaller firms sold small businesses an “Active Listening” service: a special algorithm, they said, that heard conversations through smart devices in real time and targeted ads with them. In May 2026 the Federal Trade Commission charged that the service did not listen to conversations or use voice data at all. What it did was resell email lists obtained from other data brokers, at a markup. The firms had also told clients that people had “opted in” by accepting apps’ terms of service. The FTC’s answer: clicking through mandatory terms is not consent to anything so invasive, and if the service had worked as advertised, that alone would have broken the law. The three firms agreed to pay $930,000 in all under proposed orders, which the FTC put out for public comment.
Why ads still feel like eavesdropping
An ad that matches a conversation is memorable; the hundreds that match nothing are forgotten. And the companies behind ads know a great deal without a microphone, from what you search, where your phone goes and which apps you use. The FTC case is a reminder of how that trade works: the “listening” product turned out to be a list of email addresses.
How to check your phone
- iPhone. With iOS 14 or later, an orange dot at the top of the screen means an app is using the microphone; green means the camera, or the camera and microphone. With Differentiate Without Colour turned on (Settings, Accessibility, Display & Text Size), the orange dot becomes a square.
- Android. A green indicator appears at the top right while an app uses the camera or microphone. Swipe down and tap it to see which app, and tap again to manage its permissions. On recent versions, Quick Settings has tiles that switch camera and microphone access off for every app; swipe down twice, and if the tiles are missing, add them with Edit.
- Both. The privacy part of Settings lists every app that has asked for the microphone. Switch off the ones that have no reason to hear you.
A microphone you choose
We built our ring the other way round. Lychnos Ring has no wake word: its microphone gets no power until you hold the button, so there is nothing listening in between. It is in development: hold to talk versus wake words.
Sources, read 4 November 2026: Pan and colleagues, Panoptispy: characterizing audio and video exfiltration from Android applications, Proceedings on Privacy Enhancing Technologies, 2018; US Federal Trade Commission, FTC to require Cox Media Group, two other firms to pay nearly $1 million, press release, 21 May 2026; Apple, about the orange and green indicators in your iPhone status bar; Google, check if your Android camera or microphone is on or off.
Questions
Do apps secretly record you to choose ads?
There is no good evidence that they do. Researchers who tested 17,260 Android apps in 2018 found none sending audio in their tests, though some sent screenshots and recordings of the screen. In 2026 the US Federal Trade Commission said a marketing service sold as listening to conversations did not use voice data at all.
How can I tell if an app is using my microphone?
On an iPhone with iOS 14 or later, an orange dot at the top of the screen means an app is using the microphone, and a green one means the camera. On Android a green indicator appears at the top right when an app uses the camera or microphone; swipe down and tap it to see which app.