Halkyon

Halkyon is a spaced-repetition app for your own material: studysets of
flashcards, notes, learning paths and PDFs, reviewed on an FSRS schedule. Every
studyset is made by its learners: build yours for any subject, or copy one that
someone published. It works offline and syncs between your devices.

Learn from what you watch: play films and shows from your Jellyfin server,
and every subtitle line is split into dictionary words, with readings above
and the translation below. Tap a word, and it is a flashcard.

Dictionaries for Japanese, Chinese, Korean, German, Greek and English; kanji,
hanzi and Hangul written by hand, each stroke checked; exam plans for the
JLPT, HSK and Korean levels, with a daily pace to your exam's date; and
studysets published to Explore and copied, later releases coming in as
merges that keep your own edits.

You sign in with SimpleLogin, by Proton, or with an email address, a
password and an authenticator app. It connects to halkyon.li, the project's
instance, or to any other: everything an instance needs is in the repository,
to run your own. The app is AGPL-3.0 and the server SSPL-1.0, so all of its
code is public.

Questions and reports: support@halkyon.app