What this app is, how it was built, and what it does and does not do with your use of it. The audit below backs these claims with evidence.
This project was built with AI coding assistance throughout: Claude Code (Anthropic) wrote and iterated on the app itself, its spaced-practice scheduling logic, the content-ingestion tooling used to curate the vocabulary and grammar drills, and this page. Independent AI models (including Gemini and GPT-family models) reviewed the app and its data separately, to catch mistakes the first model might miss in its own work. None of this replaces responsibility for the result.
This app collects nothing about you, and sends nothing anywhere. No analytics, no tracking pixels, no third-party scripts, no cookies. It does use your browser's local storage, on your own device, to remember your practice progress between visits - see the audit below for what that means and how it was checked.
There is no backend, no account system, no form that sends data anywhere, and no database. The app is a single static HTML file with no build step: everything it does runs in your browser, on your device. The entire source is that one file - open it in any text editor, or use your browser's "view source", to read what it does.
No ads, no paywalls, no affiliate links, no selling of data (there is no data to sell). The only monetization-adjacent thing here is a voluntary Ko-fi link: entirely optional, never required for any feature, and not tied to anything this app knows about you, because it does not know anything about you. Following that link takes you to Ko-fi's own site, governed by Ko-fi's own practices, not this one.
This documents what was checked, when, and how. Last reviewed: 2026-10-11.
| Third-party scripts | none |
| Cookies set by this app | none |
| External resource references (scripts, stylesheets, fonts, images) | none |
| fetch(), XMLHttpRequest, or <iframe> | none |
| localStorage usage | yes - on-device only: your practice statistics, level unlocks, and preferences, read and written only by this page, on your own device. Never transmitted anywhere - there is nothing in this app that could send it. |
| Network requests made when the page loads, and when practicing (answering cards, switching tabs, exporting/importing progress) | zero requests to any external domain, confirmed by capturing real browser network traffic while using the app |
The only external references anywhere in this app are ordinary hyperlinks (for example, to Tatoeba's site in the attribution note, or to Ko-fi above). A hyperlink only contacts another site if you click it; it is not a resource this page loads on its own.
Some vocabulary example sentences come from the Tatoeba project, used under the CC-BY 2.0 FR license. This is a license credit, not a network dependency - the sentences are embedded directly in the HTML file, and nothing is fetched from Tatoeba or any other site at runtime.
Checked by reading every line of the page source for script tags, external resource references, cookie or storage API usage, iframes, and network-call code, then separately verified by loading the page in a real browser and recording every network request made, including after clearing and reloading local storage and navigating through the app's tabs, to catch anything a source read-through alone might miss.
The audit above shows this app makes zero network requests once the page has loaded. A saved copy works the same way with no internet connection at all: on a plane, with wifi off, indefinitely. Loading the live page is the easiest way to try it; saving a copy is how you use it with no internet, including the first time you open it on a given device.
Quickest: download the file directly. If that doesn't start a download on your device, use your browser's own save function instead: Ctrl+S (Windows, Linux) or Cmd+S (Mac) on a computer, or the download/save option in your browser's menu on a phone or tablet.
Computer (Windows, Mac, Linux): double-click the saved file, or drag it into any open browser window.
Phone or tablet (iOS, Android): open it from your Downloads or Files app; if it doesn't open on its own,
choose "open with" and pick any browser.
Once saved, the file can go anywhere: email it to yourself, AirDrop it, copy it to a USB drive, sync it through any cloud storage. It's one ordinary file; nothing about it depends on this website.
Like a normal website: open it in a browser, nothing to install, the same file works on any computer or phone. Like an installed app: keeps working fully offline, and remembers your progress between visits.
It sits between the two, without the downsides of either. A normal website needs the internet every time you load it, even for content that never changes. A normal app needs something built separately for Windows, Mac, iOS, and Android, plus an install step through an app store. This needs the internet at most once, and the exact same file runs identically everywhere after that: no install, no store, no per-platform build.