Acuity privacy policy

1. Summary

Acuity does not collect personal data. All app data is stored locally on your device. The app does not include analytics, telemetry, advertising, or crash reporting. No account is required to use the app.

Accuracy and limitations

Acuity reads sound through the microphone built into your phone or tablet. Phone microphones are consumer audio components, not calibrated measurement instruments, so absolute decibel values vary by hardware model and by mic obstruction (case, finger, screen protector). Use Acuity for useful relative measurements (is room A louder than room B; is a sustained noise above the level at which hearing damage is a concern over time; is this instrument in tune relative to A=440 Hz). Do not rely on it for legal, occupational-safety, medical, or regulatory compliance purposes. A built-in calibration wizard lets you apply a manual offset against a trusted reference meter if absolute accuracy matters for your use case.

2. Data Acuity stores on your device

Acuity stores its working data (your settings, history, and content) in the app's private storage on your device. This data never leaves your device through Acuity. You can clear it at any time: on Android, clear the app's storage in Settings or uninstall the app; on iPhone or iPad, delete the app, which removes its on-device data.

Android's own backup system may include this data in your Google account backup if you have device backup enabled in Android Settings. That backup is controlled by Google and by your device settings; Kuroki Studio cannot access it.

On iPhone and iPad, if you have iCloud Backup or an encrypted device backup enabled, Apple's backup system may include this data. That backup is controlled by Apple and by your device settings; Kuroki Studio cannot access it.

3. Permissions Acuity requests and why

Microphone (android.permission.RECORD_AUDIO) (NSMicrophoneUsageDescription)

To read ambient sound levels and detect instrument pitch. Audio is never recorded to storage or transmitted; samples are analyzed in memory and discarded.

Internet (android.permission.INTERNET) · Android only

Declared by the Google Play Billing and RevenueCat libraries to verify and restore your one-time Pro purchase. On iPhone and iPad, network access needs no permission. Acuity makes no other network calls; your audio and readings never leave the device.

Network state (android.permission.ACCESS_NETWORK_STATE) · Android only

Declared by the same billing and RevenueCat libraries to check connectivity before a purchase or restore. No information about you is collected.

In-app billing (com.android.vending.BILLING) · Android only

Declared by Google Play Billing so you can buy and restore the one-time Pro unlock through Google Play. On the App Store, the equivalent purchase runs through Apple In-App Purchase and needs no such entry.

4. Third-party services used in Acuity

Acuity is a paid app. To process your purchase and restore it on reinstall or a new device, it uses Google Play Billing on Android, Apple In-App Purchase (StoreKit) on iPhone and iPad, and RevenueCat on both. Where an app also has an optional feature that reaches the network (for example fetching live currency rates), the service behind that feature is listed below with the exact purpose it serves and the data it receives. No third-party services beyond those listed here are used.

Google Play Billing

Purpose: Processes the in-app purchase itself. All payment handling is performed by Google.

Data shared: Whatever Google Play collects to process a purchase on your Google account. Kuroki Studio never sees your payment details.

Their policy: https://policies.google.com/privacy

Apple In-App Purchase (StoreKit)

Purpose: Processes the one-time Pro purchase on iPhone and iPad. All payment handling is performed by Apple.

Data shared: Whatever Apple collects to process a purchase on your Apple Account. Kuroki Studio never sees your payment details.

Their policy: https://www.apple.com/legal/privacy/

RevenueCat

Purpose: Verifies your purchase and restores it on reinstall or on a new device signed in to the same store.

Data shared: An anonymous app-install identifier, the store purchase token (the Google Play purchase token on Android, or the App Store transaction on iPhone and iPad), your device platform and app version, and country (derived from IP at the time of purchase). No name, email, contacts, or location is sent.

Their policy: https://www.revenuecat.com/privacy/

5. Children's privacy

Acuity is not directed at children under 13 (or the equivalent minimum age in your jurisdiction). Kuroki Studio does not knowingly collect any data from children. Because Acuity does not collect personal data from anyone, this also applies to children who use the app.

6. Your rights

Because Kuroki Studio does not hold any personal data about you in connection with Acuity, there is no personal-data record to access, correct, port, or erase on our end. To remove the app data stored on your device, clear the app's storage in Android Settings, or delete the app on iPhone or iPad. See the account and data deletion page for details.

Under Japan's Act on the Protection of Personal Information (APPI), under the EU General Data Protection Regulation (GDPR), under the UK GDPR, and under the California Consumer Privacy Act (CCPA), you have rights including access, correction, deletion, and (where applicable) the right to lodge a complaint with your data protection authority. If you have any question or request related to your privacy as it concerns Acuity, contact privacy@kurokistudio.com.

7. Changes to this policy

If Kuroki Studio changes this policy, the new version will be posted at this URL and the effective date at the top will be updated. Material changes (such as introducing a new third-party service) will additionally be noted in the app's "What's new" entry on Google Play and the App Store.

8. Contact

Kuroki Studio (Sole proprietorship, Kumamoto, Japan; D-U-N-S 699200333).
Privacy questions: privacy@kurokistudio.com
General support: support@kurokistudio.com