An Android app that tracks your hearing health in real time by monitoring the sound pressure levels you are exposed to throughout the day.
- Monitors ambient sound levels in real time using your device microphone
- Splits the audible range (20 Hz – 20 kHz) into 26 frequency bands and tracks hearing stress independently for each one
- Reports your current hearing status — Fine, Caution, Warning, or Critical
- Tells you whether your ears are currently accumulating stress or recovering from a previous exposure
- Keeps running in the background so you never miss an exposure
- Leaves the decision about further exposure in your hands — the app informs, you decide
Most hearing protection tools tell you when you have received a dangerous dose of noise. They do not tell you how long you need to wait before your ears have recovered. Sound2 fills that gap — so you always know the state of your ears before the next exposure, not after the damage is done.
| Status | What it means |
|---|---|
| 🟢 Fine | Your ears are fully recovered |
| 🟡 Caution | Minor stress — monitor your environment |
| 🟠 Warning | Significant stress — consider stepping away |
| 🔴 Critical | High stress — your ears need rest now |
Hertz and Health is not yet on PlayStore. Install the APK directly:
- Download the latest APK from the Releases page
- On your Android device, go to Settings → Apps → Special app access → Install unknown apps and allow installs from your browser or file manager
- Open the downloaded APK and tap Install
- Grant microphone and notification permissions when prompted
Requires Android 9 (API 28) or higher.
| Permission | Reason |
|---|---|
RECORD_AUDIO |
Microphone access for sound level measurement |
FOREGROUND_SERVICE |
Keeps monitoring alive when the app is backgrounded |
FOREGROUND_SERVICE_MICROPHONE |
Required on Android 14+ for mic use in a background service |
POST_NOTIFICATIONS |
Foreground service notification (Android 13+) |
Hezie — hertzhealth.com