Last updated: November 2026
By using Cadence, you agree to these terms. If you do not agree, please do not use the application.
Cadence is a free, open-source flashcard application, available on the web and as an app for Android. It runs on your device and stores your data there. A few optional features talk to a server: Google Drive sync (to back up and synchronise your data across devices), a short-lived share relay operated by the author (to hand a card pack or a tune analysis to someone else via a one-time key), lookups against TheSession.org and, if you turn it on, irishtune.info, downloads of public data (tune popularity, tune names, the recognition index), and the services behind the links you add to your cards. None of these servers keep a durable copy of your data — see the Privacy Policy for the details of what each one sees and for how long.
Tunes imported from TheSession.org or irishtune.info, players embedded from YouTube, Spotify, Deezer or SoundCloud, and files behind links belong to their authors and are subject to those services' own terms. Cadence only fetches or shows them at your request; it does not own them or vouch for them.
Tune recognition, the boundaries placed on a recording, audio sync, play-along and tempo come from automatic analysis of sound. They can be wrong — a tune missed, a tune mistaken for another, a score following the wrong place — and are offered as help, not as a measure of anyone's playing.
If you use the share-by-key feature, you're solely responsible for what you share. The relay is provided on a best-effort basis: it is intentionally ephemeral (see the Privacy Policy for the exact limits), carries no availability guarantee, and the author may restrict or discontinue it at any time without notice. The same goes for the irishtune.info import, which goes through the same server.
The Google Drive sync feature is entirely optional. When enabled, Cadence stores a data file (cadence-data.json) and a folder of larger files (cadence-data-ext) in your Google Drive, using the drive.file scope. You can disconnect and delete them at any time. Use of this feature is also subject to Google's Terms of Service.
Cadence does not keep a durable backup of your data on any external server — see the Privacy Policy for how the optional share relay and Google Drive sync handle data in transit. You are solely responsible for keeping copies of your data. The application is provided as is, without any warranty. The author is not liable for any data loss resulting from browser storage clearing, the system clearing an app's data, uninstalling the app, application bugs, or any other cause.
Cadence is open-source software, licensed under the GNU AGPL-3.0-or-later. The source code is available on GitHub. The "personal, non-commercial use" clause above applies to the hosted service at batpapa.github.io — the AGPL license itself grants broader rights (including commercial use) over the code, subject to its terms (notably section 13, which requires a network-facing modified version to also offer its source).
These terms may be updated at any time. Continued use of the application after changes constitutes acceptance of the new terms.
For any questions, write to antl@hotmail.fr, or open an issue on the Cadence GitHub repository.