Baby cry detection: how Listen Mode works

What it does

1. You choose a sound and turn on Listen Mode.
2. The app listens through the phone microphone. Nothing plays yet.
3. When it recognizes a baby crying, it starts your chosen sound.
4. When the crying stops, the sound stops after the time you chose in the settings.

Crying, not just noise

Earlier versions of this kind of feature only measure how loud the room is, so a car horn, a doorbell or a passing truck can trigger them. Listen Mode instead uses YAMNet, a general-purpose sound classifier from Google that was trained to tell more than 500 kinds of sounds apart, including a specific "baby cry, infant cry" class. The app starts your sound only when that class stays confidently detected for a moment.

It keeps working with the screen locked

The listening runs as a native background service on Android, not inside the screen you are looking at, so it keeps going when the screen is locked or the app is in the background. Android shows its usual microphone indicator while it listens. Because the microphone is in use, expect some extra battery use during long sessions.

It stops when your baby settles

In the Listen Mode settings you choose how long the sound should keep playing after the last time crying was heard: 15 seconds, 1, 5, 15, 30, 45 or 60 minutes, or until you stop it. Each time crying is heard again, the countdown starts over.

Why the sound dips briefly

A sound classifier cannot reliably hear a cry underneath loud playback, so while your sound is playing the app lowers its own volume for about a second every so often, listens in that quiet moment, then restores the volume. You may notice a short dip. It is how the app knows whether your baby is still crying.

Privacy

The recognition happens on your phone. Microphone audio is not recorded, uploaded or shared, and we cannot access it. Listen Mode only runs when you turn it on, and the app asks for microphone permission the first time you use it. See the privacy policy for the full details.

What it is not

• It is not a baby monitor and not a medical device. It does not replace being within earshot of your baby or following safe sleep guidance.
• It can miss a cry or react to something that is not a cry. Do not rely on it for safety.
• Keep the phone close enough to hear your baby, and keep the volume and distance guidance in white noise safety in mind.

Good to know

Listen Mode is part of the one-time Premium purchase, which also removes ads. There is no subscription. The rest of the app, including all 20 sounds and the sleep timer, is free. See white noise machine vs app for how a phone compares with a dedicated machine.