Lingueez · Legal
Privacy Policy — Lingueez
Last updated: 2026-07-16 · Version: 1.1
This Privacy Policy explains what personal data the Lingueez applications collect, why, and what rights you have. It covers the Lingueez desktop app and the Lingueez mobile app (Android), which share a single account and sync service. Where a practice applies to only one platform, this is stated explicitly. It is written to satisfy Articles 12–14 of the EU General Data Protection Regulation (GDPR).
ℹ️ A Ukrainian version is available here.
1. Who is responsible (Controller)
The data controller for the hosted account and sync service is:
Lingueez Email: privacy@lingueez.app
2. The short version
- Desktop: Lingueez is local-first. You can use it fully without an account, and in that mode no personal data leaves your device except for the optional online features you explicitly trigger (translation, read-aloud, AI, dictionary/web lookups).
- Mobile: the app is a companion to your synced library, so you sign in to use it. Your vocabulary is stored in the cloud and made available across your devices.
- We use no analytics, no advertising, and no tracking on any platform.
- You can delete your account at any time from within the app. On desktop you can also export all your data.
3. What data we process, and why
3.1 Account data (only when you sign in)
| Data | Source | Purpose | Legal basis |
|---|---|---|---|
| Email address | You (sign-up) or Google (if you use Google sign-in) | Create/identify your account, sign-in, account-related email (verification, password reset) | Contract — Art. 6(1)(b) |
| Account ID (UUID) | Generated by our authentication provider | Identify your account and isolate your data | Contract — Art. 6(1)(b) |
| Display name | You, or your Google profile | Show who is signed in | Contract — Art. 6(1)(b) |
| Password | You | Authenticate you (stored only as a salted hash by our authentication provider; we never see it) | Contract — Art. 6(1)(b) |
Signing in is optional on desktop and required on mobile.
3.2 Synced content (when you are signed in)
When you are signed in, the following content is stored in the cloud and associated with your account ID: your words and their definitions, tags, saved texts/reading passages (desktop), and the relationships between them, plus timestamps and status/favourite flags.
- Purpose: keep your library backed up and available across your devices.
- Legal basis: Contract — Art. 6(1)(b).
- Each user’s rows are isolated by Row-Level Security, so one account cannot read another’s data.
3.3 Data that stays on your device (never uploaded by us)
- Your listening/review history and learning-progress statistics — stored locally on the device that produced them.
- Authentication tokens — kept in your operating system’s secure credential storage where available, or otherwise in your app’s private local storage on the device. Used to keep you signed in.
- Application settings and, on desktop, local backups of your database and an offline cache of your library on mobile — all local to your device.
- Diagnostic and crash logs — local only, kept small and rotated. On desktop they are automatically redacted (email addresses, tokens and API keys are masked before being written). They are only ever shared if you choose to send them to us to report a problem.
3.4 Optional online features (you control these)
These features run only when you use them. The relevant text is sent to the third party named below at the moment you invoke the feature. Availability differs by platform:
| Feature | What is sent | To whom | Platform | Notes |
|---|---|---|---|---|
| Translation | The word/phrase/text being translated | Google (unofficial, free endpoint) | Desktop & mobile | Runs when you translate or use “Save to Lingueez”. No data-processing agreement covers this endpoint; see §5. Desktop can switch to DeepL. |
| Read-aloud (mobile) | Nothing leaves your device | — | Mobile | Mobile read-aloud uses your phone’s on-device text-to-speech engine. No text is sent to us or any third party. |
| Read-aloud (desktop, gTTS) | The text to be spoken | Google (unofficial, free endpoint) | Desktop | The desktop default. You can switch to Google Cloud TTS. |
| Read-aloud (Google Cloud TTS) | The text to be spoken | Google Cloud | Desktop | Only if you configure Google Cloud credentials. |
| Translation (DeepL) | The text being translated | DeepL SE (Germany) | Desktop | Only if you configure a DeepL API key. |
| AI definitions / text generation | Your prompt (e.g. the word, your texts) | OpenAI or Google (Gemini) | Desktop | Only if you enable AI and provide an API key. |
| Dictionary / Wikipedia / web & RSS lookups | Your search query or the URL you open | Wikipedia and the sites you choose | Desktop | Only when you search or open a source. |
- Legal basis: these features run only when you actively use them (you choose to translate, play audio, search, or generate). We rely on Art. 6(1)(b) (taking steps at your request) and, for the optional add-ons you enable, Art. 6(1)(a) (consent). You can avoid any of them by not using the feature.
3.5 Software updates
- Desktop: on startup (if enabled) the app asks GitHub whether a newer release exists. This is a plain version check; no account data or device identifier is sent. Legal basis: legitimate interest in providing security/feature updates — Art. 6(1)(f).
- Mobile: updates are delivered through the Google Play Store, which is governed by Google’s own terms and privacy policy. The app itself performs no update check.
3.6 What we do not do
No analytics, no advertising, no behavioural tracking, no profiling, no automated decision-making with legal effect, and no sale of personal data.
4. How long we keep data (retention)
- Content you delete: kept while your account exists, and when you delete individual content it is retained for a short grace period (default 30 days) so the deletion can propagate to your other devices, after which it is permanently removed.
- Deleting your account: when you delete your account, your account and all of your synced content are deleted immediately and permanently — there is no grace period and no way to recover them.
- Local data on your device (settings, cache, and — on desktop — local backups) stays until you delete it or your storage rules prune it.
- Logs rotate automatically and are capped at a few megabytes.
5. Sub-processors and international transfers
We use the following processors/sub-processors for the hosted service:
| Processor | Role | Location / transfer safeguard |
|---|---|---|
| Supabase | Database, authentication, account emails | EU region; DPA in place |
| Google (OAuth, Cloud TTS, Gemini) | Optional, user-enabled | DPA / EU Standard Contractual Clauses / EU-US Data Privacy Framework |
| OpenAI | Optional, user-enabled AI (desktop) | DPA / SCCs |
| DeepL SE | Optional, user-enabled translation (desktop) | Germany / EU |
⚠️ Unofficial Google endpoints. The default free translation (desktop and mobile) and the desktop default read-aloud use Google endpoints that are not covered by a data-processing agreement and may transfer data outside the EU without standard safeguards. They run only when you use those features. On desktop you can switch to the official, agreement-backed alternatives (DeepL, Google Cloud TTS); on mobile, read-aloud already runs entirely on-device.
6. Your rights
Depending on where you live (for example the United States — including California — or Ukraine), you have rights over your personal data: to access, correct, delete and export it, to object to or restrict certain processing, and to withdraw consent. We honor these for all users. Many are built into the app:
- Erasure: use Delete account to permanently remove your account and all synced content from the cloud. On mobile, Sign out ends your session on the device without deleting cloud data; on desktop, Remove account does the same.
- Access & portability: on desktop, use Export to download all your data in an open format. On any platform you may request a copy of your data by contacting us.
- Rectification: edit your content and profile directly in the app.
- Withdraw consent: stop using, or disable, the optional online features.
We do not sell or share your personal information for advertising. For any request, contact us at privacy@lingueez.app; we respond within 30 days. If your region has a data-protection authority, you also have the right to lodge a complaint with it.
7. Security
Data in transit is encrypted (HTTPS/TLS). Cloud data is isolated per user by Row-Level Security. Authentication tokens are stored in your operating system’s secure credential storage where available, otherwise in your app’s private local storage. Logs are redacted of secrets. No security measure is perfect, but we apply appropriate technical and organisational measures and will notify you and the supervisory authority of a personal-data breach where the law requires.
8. Children
Lingueez is not directed at children. You must be at least 13 years old to create an account (and old enough to consent to this policy under the law of your country/state). We do not knowingly collect personal data from children under 13; if you believe a child has provided us data, contact us and we will delete it.
9. Changes
We may update this policy. Material changes will be indicated by the Version and Last updated date above, and — where the change affects your account — you may be asked to re-accept the policy in the app.
10. Contact
Lingueez · privacy@lingueez.app