Privacy Policy

1. Overview

This policy covers all apps developed and maintained by Kaiyo Zero Software, an independent software studio. It currently applies to Quillen, Kaiyo Notes and Kaiyo Goals. Where behaviour differs between apps, this is stated clearly.

All Kaiyo Zero apps are built on the same privacy foundation: no accounts required, no advertising, no analytics SDKs, and no data transmitted from your device unless you explicitly choose to enable a feature that requires it.

Website (kaiyozero.com): this is separate from our apps. The website uses Microsoft Clarity, a third-party analytics service, to understand how visitors use our pages (for example which pages are viewed, clicks, scrolling, and how often download buttons are used). Clarity may set cookies and collects anonymised usage data such as device type, browser, and approximate location. It does not collect your name, email address, or other personal details, and we do not use it for advertising. Microsoft's handling of this data is described in the Microsoft Privacy Statement. The apps themselves contain no analytics.

2. Data We Collect

Kaiyo Zero apps collect no personal data by default. Our apps do not require an account and do not transmit any information from your device.

Kaiyo Notes only: if you choose to enable Google Drive Backup and Sync in settings, the app will request access to your Google account solely to read and write your backup file to your personal Google Drive. Your Google account email address is used to authenticate the connection. No other personal information is accessed or stored by Kaiyo Zero Software.

Kaiyo Goals: no data is ever transmitted from your device. All goals, habits, progress, and settings remain entirely local.

Quillen: Quillen does not require an account and does not collect or transmit your writing. The only information involved is what is needed to purchase and activate your license (see section 4). Your manuscripts, characters, lore, notes, and settings stay on your computer. The prose analysis, spellcheck, and thesaurus features are rules-based and run entirely on your device; Quillen does not use AI and your text is never sent anywhere.

3. Data Storage

All app data — notes, goals, habits, folders, tags, settings, and preferences — is stored locally on your device using Android's standard local storage. This data is only accessible to you and to the relevant Kaiyo app on your device.

Quillen: every book, chapter, scene, character, lore entry, note, and to-do is saved as plain files in the Documents folder on your own computer. There is no Quillen cloud service. If your Documents folder is already synced by a service you use, such as OneDrive, iCloud Drive, or Dropbox, your Quillen files will be synced by that service under its own terms; Quillen itself does not upload them.

Kaiyo Notes only: if Backup and Sync is enabled, a single encrypted JSON backup file is additionally written to your personal Google Drive account in a private app folder not visible to other apps or users. This data remains in your Google account and under your control at all times. You may delete it by disabling sync within the app or directly through your Google Drive settings.

4. Internet Connectivity

Kaiyo Goals does not connect to the internet at all. It is a fully offline app.

Quillen connects to the internet only to purchase and activate your license, a one-time step. Once Quillen is activated it does not access the internet again, and it works fully offline for writing, planning, analysis, and export. Your manuscript and other writing are never part of this connection.

Kaiyo Notes does not connect to the internet by default. An internet connection is only used when you have explicitly enabled Google Drive Backup and Sync in settings, and solely for the purpose of reading and writing your backup file to your own Google Drive account.

5. Third-Party Services

No Kaiyo Zero app integrates third-party analytics, advertising networks, or data sharing services. No SDKs that collect data are included in any of our apps.

Kaiyo Notes only: if Backup and Sync is enabled, the app communicates with Google Drive and Google Sign-In services. Please refer to Google's privacy policy at policies.google.com/privacy for details on how Google manages account and Drive data.

6. In-App Purchases

Where apps offer premium features, subscriptions or lifetime purchases are processed through Google Play Billing. Kaiyo Zero Software does not handle or store your payment information. Please refer to Google's privacy policy for details on how Google manages payment data.

Kaiyo Notes offers a free tier, optional premium subscriptions, and one-time purchases, all processed through Google Play Billing.

Quillen is a one-time purchase on desktop. Payment is processed by Lemon Squeezy, our payment provider and merchant of record, which uses Stripe to process payments. Kaiyo Zero Software does not handle or store your card or other payment details. Please refer to the Lemon Squeezy privacy policy for how your payment data is managed. After purchase, your license is activated once over the internet; no further connection is needed.

7. Permissions

Kaiyo Notes may request the following device permissions:

• Biometric / device credentials — used only for note locking (Premium). No biometric data is stored by the app.
• Storage / media access — used only to set a custom background image (Premium) or to export notes as .txt files (Premium). Files are only accessed when you explicitly choose them.
• Google account access — requested only if you choose to enable Backup and Sync (Premium). Used exclusively to authenticate with Google Drive. Access can be revoked at any time through your Google account settings.
• Internet access — used exclusively when Backup and Sync is enabled. Not used for any other purpose.

Kaiyo Goals may request the following device permissions:

• Notifications — used only to deliver habit reminders at the times you choose. You can deny this permission; the app remains fully functional without it, but scheduled reminders will not fire.

8. Your Data Rights

You have full control over your data at all times:

• All local data for any app can be deleted by uninstalling that app
• Kaiyo Notes: if Backup and Sync is enabled, you can delete your Google Drive backup directly within the app settings or through your Google Drive account
• Kaiyo Notes: you can revoke access to your Google account at any time via myaccount.google.com

9. Children's Privacy

Kaiyo Zero apps do not knowingly collect data from anyone, including children. In their default state, no data is collected at all. The optional Backup and Sync feature in Kaiyo Notes requires a Google account, which Google restricts to users aged 13 and over in accordance with their own terms of service.

10. Changes to This Policy

If this policy ever changes, the updated version will be published at kaiyozero.com/privacy.html with a new last updated date. When new apps are added, this policy will be updated to reflect their specific data practices.

11. Contact

If you have any questions about this policy, contact us at:
info@kaiyozero.com