Last updated: August 20, 2026
In short: HertzZen doesn't require sign-up, doesn't use the microphone, doesn't access your files, and doesn't collect data that directly identifies you.
Your settings and personal presets are stored only in the app's private storage, on your device. They're never sent to any server and are deleted when you uninstall the app or clear its data.
The app shows ads from Google AdMob. To do this, Google's SDK may process the advertising identifier, IP address (approximate location by country or region), device model, system version, language and interactions with ads — to serve, measure and prevent fraud, and to personalize ads when you authorize it. Details at policies.google.com/technologies/partner-sites.
In the European Economic Area, the United Kingdom and Switzerland, a Google consent form appears before personalized ads. Your choice is stored on the device and can be changed in Ad preferences, in the side menu. In other regions, you can limit personalization by resetting the advertising identifier in Android settings.
If the app crashes, Firebase Crashlytics receives a technical report (error stack trace, device model, Android and app version, language and a random installation identifier). It's used only to fix bugs and doesn't include your settings or data that identifies you.
Aggregated usage events are collected — such as app opens and screens visited — to understand which features are used. The information is statistical and doesn't identify you.
NOTIFICATIONS and FOREGROUND SERVICE allow playback to continue with the screen off and let you control the sound from the notification. The app doesn't request access to the microphone, camera, contacts, location, files, photos or calendar.
The app doesn't record or transmit audio; doesn't create an account or require login; doesn't collect your name, email, phone, documents, contacts or precise location; and doesn't sell data.
The only third parties are the Google services mentioned above (AdMob, Crashlytics and Analytics), each under its own privacy policy at policies.google.com/privacy. There's no sharing with any other company.
Settings stay on the device until you uninstall the app or clear its data. Crash reports and usage events follow Firebase's retention periods — typically up to 90 days for crashes and 14 months for aggregated events.
The app is not directed at children under 13 and doesn't knowingly collect data from children. Guardians can request removal via the contact below.
You can request access, correction, portability or deletion of data, and revoke consent for personalized ads. Since there's no account, most of this is done on the device itself: clearing the app's data removes local settings, and resetting the advertising identifier unlinks your ad history. For other requests, use the contact below.
Communication with Google's services is over encrypted connections, and local settings are kept in the app's private storage area.
This policy may be updated to reflect changes to the app or to the law. The revision date appears at the top of this page.
Questions or privacy-related requests can be sent to the email below. We respond within 15 days.
