Privacy Policy

This Privacy Policy applies to the Kaeru Android app, a currency converter published by Quantum Quacks (referred to as "we", "us" or "our") and distributed through the Google Play Store.

1. Data controller

• Controller: Quantum Quacks
• Website: https://quantumquacks.es
• Contact email: contacto@quantumquacks.es

2. Summary: Kaeru itself does not collect personal data

Kaeru has no user accounts, no advertising, no analytics and no tracking. Its only third-party SDK is Google's Play Billing Library, for the optional purchase described in section 7. Apart from what Google Play reports to us about that purchase, we do not collect, receive or store any personal data. Everything the app keeps stays on your device.

3. Data stored on your device

Kaeru keeps the following in its private storage on your device:

• The last exchange rates it downloaded, so that it works offline.
• The two currencies you selected and the last amount you typed.
• Whether it has already offered you the home-screen widget.
• When your free trial started, whether you bought the unlock, and the price Google Play showed.

None of this leaves your device, and it is excluded from Android backups. To delete it, clear the app's storage or uninstall the app.

4. Internet connection: exchange rates

To keep rates up to date, Kaeru downloads a public file in the background, about once a day, from the open exchange-api project. The file is served by jsDelivr (cdn.jsdelivr.net) or, as a fallback, by Cloudflare Pages (latest.currency-api.pages.dev).

These are standard requests for the same public file everyone gets. They contain no personal data, no identifier, and neither the currencies you use nor the amounts you type. As with any request on the internet, those providers can see your IP address and basic technical details of the request. We do not receive that information. Their own privacy policies apply to it.

5. Permissions

Kaeru requests INTERNET, to download the rates and reach Google Play; ACCESS_NETWORK_STATE, so that it waits for a connection before trying; and com.android.vending.BILLING, to offer the purchase through Google Play. It does not access your location, contacts, files, camera or microphone.

6. Home-screen widget

The widget shows the same amounts as the app, on your home screen. Your launcher displays it on your device, and we receive nothing from it.

7. Google Play and the optional purchase

Google Play handles downloads and updates under Google's Privacy Policy. Google gives developers aggregated statistics, such as install counts, and crash and performance reports from people who chose to share them with Google. We use these only to improve the app. They do not identify you.

After a free trial, the widget and changing currency can be unlocked with a one-time purchase through Google Play. Google handles the payment, and we never see your card or payment details. The app uses Google's Play Billing Library to show the price and to ask Google Play whether your Google account owns the unlock, including after a refund. The library talks to Google Play and may send Google technical information about how billing works on your device. Google's Privacy Policy applies to all of this.

If you buy the unlock, Google Play gives us a record of the order, such as its number, the product, the price, the date and the country. We use it for accounting, and to deal with refunds or questions you send us, and we keep it as long as tax and accounting law requires.

8. Children

Kaeru is a general-purpose tool and is not directed at children. The app itself collects no personal data from anyone, including children.

9. Your rights

Unless you bought the unlock, we hold no personal data about you, so there is nothing for us to access, correct or delete. If you bought it, we hold only the order record described in section 7. If you have any request or question about your data, write to us and we will answer.

10. Changes to this policy

We may update this policy to reflect legal, technical or service changes. The current version will always be published at this URL, with an updated "Last updated" date.

11. Contact

If you have any questions about this Privacy Policy, contact us at contacto@quantumquacks.es.