Privacy Policy

Introduction

Welcome to Hikara. We are committed to protecting your privacy and ensuring you have a positive experience on our platform. This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our service.

Hikara is a book visualization and recommendation platform that helps readers discover connections between books in their library using AI-powered analysis. Your privacy is important to us, and we are committed to being transparent about our data practices.

Information We Collect

Account Information

When you create an account, we collect:

• Email address (required for authentication)
• Name (optional, from Google OAuth or manual entry)
• Profile photo/avatar (if you sign up with Google OAuth)

Book Library Data

We collect and store information about the books in your library:

• Book titles, authors, descriptions, and cover images (from Google Books API)
• Your reading status (Want to Read, Reading, Read)
• Your ratings (1-5 stars)
• Your personal notes and highlights
• Dates when books were added to your library
• ISBN identifiers (when available from Google Books)

Connection Data

Our AI generates connections between books in your library:

• Connection types (Echoes, Challenges, Bridges)
• Connection strength scores
• AI-generated explanations of how books relate

Technical Data

We automatically collect certain information when you use Hikara:

• Browser type and version
• Device information
• IP address
• Pages visited and features used
• Session duration and interaction patterns

How We Use Your Information

We use the information we collect to:

• Provide personalized book recommendations: Our AI analyzes your library, ratings, and notes to suggest books tailored to your interests
• Generate connection analysis: We identify and explain relationships between books based on themes, concepts, and your personal insights
• Authenticate your account: Verify your identity and provide secure access to your data
• Improve our service: Analyze usage patterns to enhance features and user experience
• Communicate with you: Send service-related notifications and respond to your inquiries
• Maintain security: Detect and prevent fraud, abuse, and security incidents

Data Storage & Security

Your data is stored securely using industry-standard practices:

• Database encryption: All data is encrypted at rest in our PostgreSQL database hosted on Supabase
• Secure connections: All data transmissions use HTTPS/TLS encryption
• Authentication: Passwords are hashed using industry-standard algorithms; we never store plain-text passwords
• Limited access: Only authorized personnel have access to production systems
• No data selling: We will never sell your personal information to third parties

Third-Party Services & Data Sharing

Hikara integrates with the following third-party services:

Google Books API

We use Google Books API to retrieve book metadata (titles, authors, descriptions, cover images, ISBNs). Your search queries are sent to Google to find books. Google's privacy policy applies to this data:https://policies.google.com/privacy

Google OAuth

If you choose to sign up with Google, we receive your email address, name, and profile photo from Google. We use this information solely for authentication and account creation. Google's privacy policy applies.

Supabase

We use Supabase for database hosting and authentication infrastructure. Supabase has access to your encrypted data as our infrastructure provider. Supabase privacy policy:https://supabase.com/privacy

OpenRouter/Anthropic (Claude AI)

We use Claude AI (via OpenRouter) to analyze book connections and generate recommendations. Book titles, authors, descriptions, and your personal notes are sent to the AI for analysis. OpenRouter and Anthropic do not retain this data after processing. Anthropic privacy policy:https://www.anthropic.com/privacy

Google Analytics

We use Google Analytics to track usage patterns and feature adoption (with IP anonymization enabled). Google's privacy policy:https://policies.google.com/privacy

We do not share your data with third parties for advertising or marketing purposes. Data sharing is limited strictly to service functionality as described above.

Your Rights & Choices

You have the following rights regarding your personal data:

• Access: You can view all your book data, ratings, and notes at any time through your library
• Modification: Update or delete your book ratings, notes, and reading status anytime
• Data export: Request a copy of your data in JSON format (contact us at the email below)
• Account deletion: Delete your account and all associated data permanently (this action cannot be undone)
• Cookie preferences: Manage your cookie preferences using the button below
• Email preferences: Opt-out of non-essential communications

To exercise these rights, please contact us at the email address provided in the Contact section below.

Cookies & Tracking

We use the following types of cookies:

• Essential cookies: Required for authentication and core functionality (cannot be disabled)
• Analytics cookies: Google Analytics with IP anonymization (can be disabled)
• Preference cookies: Remember your settings and choices (can be disabled)

We do not use third-party advertising cookies or tracking pixels. You can manage your cookie preferences at any time:

Data Retention

• Account data: Retained until you delete your account
• Book library data: Retained until you manually delete books or your account
• Connection data: Automatically deleted when related books are removed
• Deleted account data: Permanently removed from our systems within 30 days of deletion request

Children's Privacy

Hikara is not intended for users under the age of 13. We do not knowingly collect personal information from children under 13. If you believe we have inadvertently collected information from a child under 13, please contact us immediately, and we will delete it.

Changes to This Privacy Policy

We may update this Privacy Policy from time to time to reflect changes in our practices or for legal, operational, or regulatory reasons. When we make material changes, we will:

• Update the "Last updated" date at the top of this page
• Notify you via email (if you have an account)
• Display a prominent notice on our website

Your continued use of Hikara after changes are posted constitutes your acceptance of the updated policy.

Legal Basis for Processing (GDPR/CCPA)

If you are in the European Economic Area (EEA) or California, you have additional rights:

GDPR (EU Residents)

• Lawful basis: We process your data based on your consent and our legitimate interest in providing the service
• Right to erasure: Request complete deletion of your data
• Right to portability: Receive your data in a machine-readable format
• Right to object: Object to processing of your data for specific purposes
• Right to restrict: Limit how we process your data

CCPA (California Residents)

• Right to know: Request disclosure of data collection and sharing practices
• Right to delete: Request deletion of your personal information
• Right to opt-out: Opt-out of the sale of personal information (we do not sell your data)
• Non-discrimination: We will not discriminate against you for exercising your privacy rights

Contact Information

If you have questions about this Privacy Policy or wish to exercise your data rights, please contact us at:

Consent

By using Hikara, you consent to this Privacy Policy and agree to its terms. If you do not agree with this policy, please do not use our service.