Privacy Policy
Language Flashcards by Longfellow Labs
Effective date: 2026-09-02
Summary
The flashcards themselves run entirely on your device — we do not collect what you study, your progress, or any other personal data. There are three narrow exceptions:
- Google Analytics (web version only) records anonymous page-view traffic.
- The optional ChatGPT tutor link (web and native) opens chatgpt.com when you tap it; no flashcard content is sent with the link.
- The Translate button on the Custom Cards page (web and native) sends the text you typed to Google Translate when you tap it.
Details below.
What stays on your device
To remember your preferences and progress between sessions, the app stores the following locally on your device using localStorage:
- Your selected lesson, voice, and other display settings (e.g. recall direction, speech-playback mode)
- Which card you were last viewing within a lesson, plus the order in which cards appear (so a shuffled deck stays put across sessions)
- Any cards you've archived or starred
- Your best completion times for the Memory Squares game (the game itself draws from the same active-deck card list noted above; it does not store a separate history)
This information never leaves your device. We have no way to access it. You can clear it at any time by uninstalling the app or clearing site data in your browser.
Audio and content
Built-in vocabulary audio is bundled with the native iOS and Android apps at install time, so playing it there never contacts a server. On the web it is served as ordinary same-origin static mp3 files: playing a clip your browser hasn't already cached fetches it from the same server that hosts this site (which may log that request like any other page asset), and no third party is involved.
Cards you create yourself on the Custom Cards page have no pre-rendered audio, so the speaker buttons on those cards (and on Memory Squares tiles backed by a custom card) instead use your device's text-to-speech engine: the browser's Web Speech API on the web and the native TextToSpeech engine on iOS/Android. Both speak the text you typed locally; we do not send it anywhere for playback. However, on the web some browsers (notably Chrome on desktop) implement Web Speech using cloud-backed voices whose audio is generated by the browser vendor's servers rather than entirely on-device — the choice of voice is controlled by your browser, not by this app.
Analytics (web only)
The web version (this site) loads Google Analytics 4 to count anonymous page views so we can see roughly how many people are using the site. Google Analytics may set its own cookies and collect data such as your approximate location (from IP), browser, and the pages you visit on this site, subject to Google's privacy policy. We do not associate this data with your flashcard activity or any personal identifier.
The native iOS and Android apps do not load Google Analytics.
External links
The "Useful links" section contains links to external sites (for example, YouTube videos). When you tap one, you leave our app and open the destination in your browser or the corresponding app. The destination's own privacy policy then applies. We do not track which links you follow.
Custom Cards translation (web and native)
The Custom Cards page lets you write your own flashcards. If you tap the "Translate" button (or save a card with only one side filled in), the text you typed is sent over HTTPS to Google Translate in order to suggest a translation. Only the text you explicitly enter into a card and choose to translate is sent; nothing else from your progress, settings, or device is included. The card text you type and your IP address are subject to Google's privacy policy; please do not type personal or sensitive information into a custom card you intend to translate.
ChatGPT tutor link
The header includes an optional link to a ChatGPT tutor (a custom GPT named "Astrid" or "Sven", depending on the selected voice) for free-form conversation practice in the language you're learning. When you tap the link, the app opens the custom GPT's URL on chatgpt.com in your browser. The app does not prefill any of your flashcard content into the message box — nothing from your progress, settings, or device is sent along with the link.
Once on chatgpt.com, OpenAI's privacy policy applies to whatever you do there. We have no relationship with OpenAI and do not see, log, or receive the messages you exchange with the tutor.
Children
The app is suitable for all ages and does not knowingly collect personal information from children under 13.
Changes to this policy
If a future version of the app handles data differently, we will update this policy and revise the effective date above. Any new data collection will also be declared on the App Store and Google Play listings before you install or update.
Contact
The Longfellow Labs language flashcard apps (Swedish Flashcards with Audio, French Flashcards) are operated by Longfellow Labs LLC.
Questions about this policy: ben@longfellowlabs.com