Privacy in Lingua
Controller and contact
Osvaldo Martinez Lopez, using the personal brand MeXeM. Contact: contact@mexem.dev. Updated October 2, 2026.
Data and purposes
ChatGPT supplies your identifier, name and email to create and protect your account. Lingua stores levels, aggregate assessment results, preferences, resource status, favourites, notes and activity dates to organise and sync learning. It does not store ChatGPT passwords or conversations, or individual assessment answers.
Providers
Authentication and hosting use OpenAI ChatGPT/Sites and Cloudflare Workers/D1. Native session credentials are protected in Keychain or Android Keystore. Providers may process technical data and store it in other countries under their terms. Storage location, provider technical logs and all provider retention periods have not been confirmed.
Apple sign-in on iOS
When enabled, Apple supplies an identifier and, if you allow it, a name and email that may be a private relay address. Lingua stores the account link and an encrypted refresh token to revoke access when you delete your account. Accounts are not merged by email and Apple passwords are never received. Apple processes authentication under its own policy.
Bug reports
Reports are private to the administrator and contain steps, results, screen, version and language. Signed-in reports are linked to a hash of the account ID for quotas; this is pseudonymous data. No screenshots, IPs, learning notes or logs are attached. Automatic redaction is imperfect: do not include personal information. For analysis with Codex, the administrator may provide a redacted export without the account hash; Codex processes report content under the terms of the account used.
Voluntary contributions
The support area opens Stripe or PayPal for external payments. Lingua does not collect or store card or bank details and does not send your account identity, session or progress to the payment link. The provider applies its own privacy policy and may share payer details and receipts with MeXeM to manage contributions. Contributions are optional and do not unlock extra features.
Retention and deletion
Learning data remains while you keep your account. Delete your account in app Settings or the web account page. Confirmed deletion removes active data, linked reports and Lingua sessions; it preserves your ChatGPT and Apple accounts and revokes linked Apple authorization. Reports older than 180 days are cleaned in opportunistic batches, without a guaranteed deadline. Local exports and hosting backups require separate handling: contact us to request it. Provider backup retention is not yet confirmed.
Your options
You can view and correct levels, preferences and notes in the app. For data access, a copy, correction, export deletion or questions, contact contact@mexem.dev. Revoked accounts can use /account on the web to delete their data. Signing in after deletion creates a new account. We do not use advertising or sell learning data.
External links, speech and security
Resources open third-party sites with their own policies. Speech uses browser or operating-system tools; some voices need network access. Sessions expire after 30 days. Saving requires a connection; unconfirmed changes may be lost when the app closes. Access controls and protected credentials reduce risk but do not make the service invulnerable.