The short answer: a voice assistant (Siri, Google Assistant or Alexa) waits for its wake word, such as “Hey Siri” or “Alexa,” before it starts recording a request. Other apps need your permission before they can use the microphone, and both iPhone and Android show a colored light whenever the mic is on. Ads that seem to “know” what you talked about usually come from online tracking: your searches, the websites and apps you use, and your location (FTC). You can check both in a few minutes.
Why ads seem to read your mind
The FTC explains that websites and apps track what you do online using cookies, tracking pixels and a phone’s advertising ID. Advertisers then show you “personalized ads based on your browsing history or your location.” Tracking companies can follow you across most of the websites you visit (FTC).
So if you chatted with a friend about new shoes, chances are one of you searched for shoes, visited a store’s website, or was standing in a shoe store with location turned on. That online trail is often enough to put a shoe ad in front of you.
See fewer personalized ads
- Your phone has a setting to stop personalized ads from Apple or Google. It’s in the “advertising” part of your phone’s privacy settings (FTC).
- Clear your browser’s cookies and history. Look at which apps can see your location, and turn it off for apps that don’t need it.
- You’ll still see ads. They just won’t be based on what you’ve done online.
How to tell if your microphone is on
iPhone
- An orange dot at the top of the screen means an app is using the microphone. A green dot means the camera is on, or the camera and microphone together (Apple).
- Swipe down into Control Center to see which app recently used them (Apple).
- To see and change which apps can use the mic, go to Settings > Privacy & Security > Microphone and turn off any app you don’t trust (Apple).
Android
- On Android 12 and newer, a green indicator appears in the top-right corner when an app uses the mic or camera. Swipe down and tap it to see which app (Google).
- For a 24-hour history, go to Settings > Security and privacy > Privacy dashboard (Google).
- Many phones also have a microphone on/off button in Quick Settings (Google).
Amazon Echo (Alexa)
Press the microphone button on top of the Echo. A red light means the microphones are off. Press it again when you want Alexa back (Amazon).
When to worry
A colored mic light is normal when you’re on a call, recording a voice message or using voice typing. Be concerned if the light keeps coming on while you aren’t using anything, or if an app you don’t recognize has microphone access. Delete that app, and see our guide on signs someone may be spying on your phone.
