Privacy Policy

Lingvestor (“we”, “us”, “our”) is a vocabulary learning platform that lets you capture words while browsing and study them with spaced repetition. This policy explains what data we collect, why, and how we protect it.

Lingvestor is currently in open beta. By using the service you agree to this policy.

The data controller for your personal data is:

Lingvestor UG (haftungsbeschränkt)
Kolonnenstr. 8, 10827 Berlin, Germany
Represented by: Anton Galkin (Geschäftsführer)

Contact email: info@lingvestor.ai

For full legal details, see our Impressum.

Account information

When you sign in with Google we receive your name, email address, and profile photo from Google. When you sign in with Apple (iOS), we receive your name and email address. We do not receive your passwords.

Words you capture

When you use the Chrome extension to save a word, we store:

• The word or phrase
• The sentence it appeared in (context)
• The URL and domain of the page you saved it from
• The date captured
• AI-generated flashcard content (definition, example sentences, translations)

We only store URLs of pages where you explicitly save a word — not your general browsing history. We do not share this information with any third party for advertising or tracking purposes.

Study activity

We store your review history (scores, intervals, next review dates) to power the spaced repetition algorithm. This data lives in your account only.

Usage data

We collect basic API usage counts per account (number of AI requests) to enforce fair-use limits. We also record the type of device you sign in from (platform, operating system, browser name) so we can support the devices people really use.

For overall site statistics we use Vercel Web Analytics. It works without cookies, shows us only aggregated page-view counts, and does not follow you across other websites. We do not use advertising trackers or pixels.

We process your personal data on the following legal bases:

• Performance of a contract — processing necessary to provide the Lingvestor service you have signed up for (authentication, storing your words, running spaced repetition, generating flashcard content).
• Legitimate interest — enforcing fair-use rate limits, keeping the service secure, and understanding aggregate usage (cookieless page statistics, device type).

We do not use your data for advertising or third-party tracking. We do not use your personal data or vocabulary content to train AI models. No data is sold to third parties.

• To authenticate you and sync your vocabulary across devices
• To generate AI flashcard content for words you save
• To run spaced repetition scheduling
• To generate podcast audio for your decks
• To enforce per-account rate limits on AI features

We do not sell your data, share it with advertisers, or use it to train AI models.

We use the following services to operate Lingvestor. Each acts as a data processor on our behalf:

Each provider has its own privacy policy. We pass only the minimum data required for each service to function.

Some of the third-party processors listed above operate outside the European Economic Area (EEA):

• Our AI text provider processes text you submit (words and context sentences) on servers outside the EU/EEA. This is necessary to generate flashcard content and word suggestions. By using these AI features, you acknowledge that your submitted text is transferred internationally.
• Vercel and Supabase may serve or cache data through infrastructure in the United States or other regions depending on your location and their CDN routing.

Data is transferred to these providers only as strictly necessary to operate the service. We do not transfer your data internationally for any other purpose.

Your data is stored in Supabase (EU primary region). Row-level security ensures that each user can only access their own data — even at the database level. All connections are encrypted in transit via TLS. We do not store payment data.

We retain your personal data for as long as your account is active. If you delete your account, all associated data (words, decks, review history, flashcard content) is permanently deleted. After account deletion, we may retain anonymised aggregate statistics that cannot be linked back to you.

You can delete your Lingvestor account directly from within the app. Account deletion cascades to all associated data: your saved words, decks, flashcard content, and study history are permanently removed.

You may also request account deletion by emailing info@lingvestor.ai. We will process deletion requests within 30 days.

As a data subject under GDPR, you have the following rights regarding your personal data:

• Right of access — you can request a copy of the personal data we hold about you.
• Right to rectification — you can ask us to correct inaccurate or incomplete data.
• Right to erasure — you can request deletion of your personal data (see “Account & data deletion” above).
• Right to data portability — you can request your vocabulary data in a machine-readable format. Your words are stored as structured data; we will provide an export on request.
• Right to restriction of processing — you can ask us to restrict how we use your data in certain circumstances.
• Right to object — you can object to processing based on legitimate interests.

To exercise any of these rights, contact us at info@lingvestor.ai. We will respond within 30 days. You also have the right to lodge a complaint with a supervisory authority (in Germany: the Datenschutzaufsichtsbehörde of your federal state).

Lingvestor uses essential browser storage to keep you signed in and remember settings you choose, including your interface language. We do not use advertising or cross-site tracking cookies. We collect aggregate site statistics without setting analytics cookies.

Lingvestor is not directed at children. You must be at least 16 years old to use the service. We do not knowingly collect data from anyone under 16.

We may update this policy as the product evolves. Material changes will be announced via the app. The date at the top of this page always reflects the latest revision.

Questions, data requests, or deletion requests: info@lingvestor.ai

For legal details about the controller, see our Impressum.