Privacy Policy

yasuworks.com ("the Operator") sets forth the handling of user information in the diary application "Nickie" ("the App") as follows.

1. Basic Principles

• The App can be used without creating an account. In that case, diary entries are stored only on the device and are not sent to the Operator.
• When you create a Nickie account, diary entries (text, photos, mood, emotion labels, etc.) are encrypted on the device before being synchronized with the server and automatically backed up. The encryption key is protected by the user's passkey, and the Operator cannot read the content of the diary entries.

2. Information We Collect

When you create an account, the Operator collects the following information.

Information	Details
Profile	ID, display name, icon image, sticker shape, group names, and group icons. Not encrypted, so that group members and people you invite can see them. Besides the Operator, they can be seen by members of the same group, people with a pending invitation, and anyone logged in who searches for your exact ID
Passkey information	Passkey public key, credential storage type, creation date and time, and last used date and time. Private keys and biometric information are never collected
Encrypted diary entries	Encrypted diary entries and photos. The Operator cannot read the content
Logged-in devices	The model name and OS of each device where you are logged in, and when it was last used. Shown to you in the App so you can log out other devices
Usage records	Timestamps of received entries, entry count, data size, and login timestamps
Technical information	IP address used during communication, device, OS, and app version information
App diagnostic information	Information when the app terminates abnormally (device, OS, app version, error log). Diary contents are not included. Sent even without an account. You can turn this off with “Send crash reports” in Settings
Purchase information	Products purchased within the app and timestamps. Payment details (credit card numbers, etc.) are not collected

3. Purpose of Use

• Providing the App (login, sync and backup, displaying logged-in devices, etc.)
• Preventing unauthorized use and responding to inquiries
• Investigating issues and improving the App
• Delivering purchased products and restoring purchases

Because the contents of diary entries are encrypted, they are not used even for the purposes above.

4. Third-Party Services

The App uses the following services. These service providers handle information in accordance with their respective privacy policies.

Service	Provider	Purpose
Cloudflare	Cloudflare, Inc. (USA)	Servers and data storage
Firebase Crashlytics	Google LLC (USA)	Collection of app crash information
RevenueCat	RevenueCat, Inc. (USA)	In-app purchase management
Google Play / App Store	Google LLC / Apple Inc. (USA)	App distribution and payment

These providers are located in the United States, and information may be stored in foreign countries such as the United States. Information regarding the personal data protection systems in the United States can be reviewed on the Personal Information Protection Commission's website. Each provider implements measures to protect personal information.

5. Provision to Third Parties

The Operator will not provide personal information to third parties without the user's consent, except as required by law. Furthermore, because encrypted diary entries cannot be read by anyone, including the Operator, their content cannot be disclosed even if requested.

6. Retention Period and Deletion

• Information is retained while the account exists.
• You can delete your account at any time from the App settings. Upon deletion, the account, profile, passkey information, encrypted diary entries, and photos stored on the server will be deleted immediately. This action cannot be undone.
• Diary entries stored on the device remain on the device even after the account is deleted.
• Passkeys saved to your device's credential storage (such as a password manager) can be deleted directly from that storage.
• If you cannot use the app, see the Account Deletion page for how to request deletion.

7. Security Measures

• Diary entries and photos are encrypted on the device before transmission (AES-256-GCM). The encryption key is protected by a passkey, and only the encrypted key is stored on the server.
• All communications are encrypted (HTTPS).
• Session tokens for authentication are stored as hashes on the server.

8. Children's Privacy

Users under the age of 16 must obtain the consent of a parent or guardian before creating an account.

9. Requests for Disclosure and Inquiries

If a user requests disclosure, correction, suspension of use, or deletion of their retained personal data, the Operator will respond in accordance with laws and regulations after confirming the user's identity. Please contact the contact point below.

10. Revisions

This policy may be revised as necessary. If significant changes occur, notice will be provided within the App.

11. Contact

yasuworks.com
Email: support@nickie.app