Fern

Fern is a beautiful flashcard app for learning languages. Words come from where you actually meet them: the book you are reading, a video with subtitles, a photo of a page. Everything runs on your device, with no account, no cloud and no ads.

SMART REVIEW
An FSRS scheduler brings a word back exactly when memory starts letting go of it. The "At risk of forgetting" section gathers what is about to slip, and "Best time to study" points to the hour when your sessions work best. The algorithm tunes itself from your own review history.

12 STUDY MODES
Learn, Flashcards, Test, Match, Write, Dictation, Build a phrase, Audio, Context, Hard words, Speed review, Cram. The Learn mode walks each word up the ladder of mastery on its own, from recognition to free recall.

FROM BOOKS
An EPUB, FB2, TXT and SRT reader with tap-to-translate. Chapters, bookmarks, reading themes, read-aloud, paged and scrolling layouts, bilingual view with a paragraph translation. Smart analysis shows how much of a text you already know and which words to learn first.

FROM VIDEO
Paste a link to a video with subtitles and the lines turn into cards with translation and real-voice audio, while the video itself reads in karaoke mode.

FROM PHOTOS
Snap a page and Fern recognises the text, then offers the unfamiliar words as cards. Recognition works offline for Latin script.

QUICK CAPTURE
A word from the clipboard, a word from the system Share sheet, an article by URL. A card takes a couple of taps, translation included.

GRAMMAR ON THE CARD
Verb conjugation and noun forms for Spanish, French, German, Italian, Portuguese and Russian, right on the back of the card.

MOTIVATION
Daily goals with a progress ring, a study streak with freeze shields for the day you miss, achievements and weekly stats: vocabulary composition, parts of speech, activity heatmap, review forecast.

MATERIAL YOU
Deep green theme, system dynamic colours, light and dark schemes, switching by time of day. Large tiles and live animation throughout.

LANGUAGES
Interface in English, Russian, German, French, Spanish, Italian and Portuguese. Over 55 study languages, plus your own custom ones. Ready-made starter decks, deck import from Anki (.apkg), CSV and TSV, vocabulary export.

PRIVACY
Decks, words and stats stay on the phone. No analytics, no cloud backup. A backup is an ordinary file you keep yourself, and restoring it can either replace everything or merge only what is new.

Fern is free software under GPL-3.0.