FreeLingo

1. Overview

FreeLingo is available as a self-hosted application and as a hosted service. For self-hosted deployments, all data is stored exclusively on the operator's server and the FreeLingo project authors have no access to it. For the hosted service, the FreeLingo team acts as the data controller and this policy describes how your personal data is collected, used, and protected.

2. Data We Collect

FreeLingo is not directed at children under 16. We do not knowingly collect personal data from anyone under 16 years of age. If you are under 16, do not create an account or provide any personal data. When you create an account and use FreeLingo, the following data is stored:

• —Username, display name, and email address.
• —Hashed password (bcrypt — your plain-text password is never stored).
• —Native language preference and learning settings.
• —Optional profile avatar image.
• —Chat and conversation history with the AI tutor.
• —Flashcard decks, study progress, and spaced-repetition data.
• —Assessment results and curriculum progress.
• —Subscription status, plan type, and Stripe customer identifier (for paid service subscribers).

3. How We Use Your Data

Your data is used exclusively to provide the FreeLingo learning experience:

• —Authenticating you and maintaining your session.
• —Personalizing your study plan and tutor interactions.
• —Tracking your learning progress over time.
• —Generating contextual AI tutor responses.

Your data is never sold, rented, or shared with third-party marketing services.

4. External AI Services

In the hosted service, AI chat, voice synthesis (TTS), and voice transcription (STT) are provided via OpenAI's API. Your conversation content and audio are sent to OpenAI for processing, subject to OpenAI's Privacy Policy (openai.com/privacy). Payment processing is handled by Stripe, Inc. (USA); Stripe processes payment data directly and we do not store payment card details on our servers — your transaction data is subject to Stripe's Privacy Policy (stripe.com/privacy). For self-hosted deployments, the operator chooses the AI provider; by default a local Ollama instance is used and no data leaves the server.

5. Cookies & Session Tokens

FreeLingo uses two technical cookies strictly necessary for the service to function: a refresh_token (httpOnly, 30-day expiry) used for session authentication, and NEXT_LOCALE (1-year expiry) to remember your language preference. No tracking, analytics, or advertising cookies are used.

6. Your Rights (GDPR)

If you are in the European Economic Area, you have the right to: access the personal data we hold about you; request correction of inaccurate data; request deletion of your account and all associated data (available directly from the Settings page); object to processing; and request data portability. To exercise these rights, contact us at the address in section 8 or delete your account directly from Settings. Legal basis for processing (Art. 6(1)(b) GDPR): we process your personal data because it is necessary for the performance of the contract between you and us — providing the FreeLingo learning service. International transfers: when using the hosted service, your conversation content and audio may be processed by OpenAI, Inc. (USA), and payment data is processed by Stripe, Inc. (USA). These transfers are carried out under the Standard Contractual Clauses approved by the European Commission (Art. 46 GDPR), ensuring an adequate level of protection. Right to lodge a complaint: you have the right to lodge a complaint with the Spanish Data Protection Authority (AEPD — aepd.es) or with the supervisory authority in your country of residence.

7. Data Retention & Deletion

Your data is retained for as long as your account exists. You can permanently delete your account and all associated data at any time from the Settings page. Deletion is immediate and irreversible.

8. Contact

For privacy-related concerns about the hosted service, contact us at: freelingo@arturocarreterocalvo.com. For self-hosted deployments, contact the administrator of the instance you are using. For questions about the FreeLingo open-source project, visit the project repository on GitHub.