Privacy Policy

We collect information you provide directly, information created by your use of the product, and limited technical information needed to run the Service.

• Account information, such as name, email address, authentication provider details, and account timestamps.
• Authentication information, such as password hashes for email/password accounts, OAuth account identifiers, sessions, and verification tokens.
• Workspace content, including notes, note bodies, signals, tags, topics, summaries, open questions, canvases, canvas nodes, canvas edges, imports, and exports.
• Billing information, such as Stripe customer IDs, subscription IDs, price IDs, subscription status, trial status, and billing portal activity. Full payment card details are processed by Stripe and are not stored by Underline.
• Security and diagnostic information, such as hashed IP-derived fingerprints, user agent strings, security event types, timestamps, and server logs.
• Analytics information from Google Analytics, such as page views, approximate location, browser/device data, and interaction signals, depending on your browser and consent settings.

We use information to provide, protect, improve, and support Underline. This includes:

• creating and managing accounts, sessions, sign-in, and sign-out;
• saving, displaying, searching, organizing, importing, and exporting your content;
• running user-triggered AI features such as signal extraction, topic suggestions, summaries, related-note suggestions, and map conversion;
• processing subscriptions, trials, cancellations, invoices, and customer portal sessions through Stripe;
• preventing abuse, rate-limiting sign-in and signup attempts, detecting security events, and enforcing Terms;
• understanding product usage and improving the public website and app experience.

AI organization is not automatic. When you request an AI feature, the relevant note content and context may be sent to OpenAI or another configured AI provider to produce the requested output. If no AI API key is configured, Underline uses local mock responses. You should avoid submitting sensitive information to AI features unless you are comfortable with that processing.

We do not sell your personal notes or workspace content. We share information only as needed to operate the Service, comply with law, or protect rights and safety.

• Hosting and infrastructure providers that run the application, database, deployment, logs, and networking.
• Authentication providers, such as Google or Apple, when you choose to sign in with those providers.
• Stripe for checkout, subscriptions, trials, billing portal sessions, invoices, and payment processing.
• OpenAI or another configured AI provider when you explicitly use AI-powered features.
• Google Analytics for website and product analytics, subject to applicable consent and browser controls.
• Legal, compliance, and safety disclosures when required by law or needed to protect users, the Service, or others.

Underline uses cookies and similar storage for authentication sessions, security, preferences, and analytics. You can control many cookie settings through your browser. Blocking cookies may prevent account sign-in or other core features from working.

We retain account and workspace data while your account is active or as needed to provide the Service, comply with legal obligations, resolve disputes, enforce agreements, and maintain security. Some records, such as billing records and security logs, may be retained for longer where required or appropriate. If you request account deletion, we will delete or de-identify personal information unless retention is required by law or legitimate security, billing, or operational needs.

Depending on where you live, you may have rights to access, correct, delete, export, restrict, or object to certain processing of your personal information. You can export supported workspace data from the app where available. To make a privacy request, contact us using the email below. We may need to verify your identity before completing a request.

Underline and its providers may process information in the United States and other countries where service providers operate. Those countries may have different data protection laws than your location. Where required, we rely on appropriate safeguards for international transfers.

Underline is not directed to children under 13, and we do not knowingly collect personal information from children under 13. If you believe a child provided personal information, contact us so we can take appropriate action.

We may update this Privacy Policy as the product, laws, and providers change. If changes are material, we will take reasonable steps to notify users. The effective date shows when this Policy was last updated.

Privacy questions and requests can be sent to privacy@useunderline.app.