CardMaster

CardMaster turns everything you learn into something you actually remember. FSRS powers spaced repetition; FIRe makes systematic knowledge easy to remember. 🧠 FLASHCARDS POWERED BY FSRS-5 Most flashcard apps guess. CardMaster computes. Every card gets its own three-dimensional memory profile — difficulty, stability and retrievability — scheduled by FSRS-5 so each review lands right before you forget. Forgotten cards come back automatically. Anki user? Import .apkg / .colpkg decks directly. 🌳 SKILL TREES POWERED BY FIRe Build knowledge as a living tree, on the same memory engine that powers Math Academy. Each node carries its own memory score that decays over time and schedules review the moment it drops. Master a parent and its children grow too (⚡). Fail a child and its parents get revisited (🌱). Review intervals grow naturally: 1→2→3→5→7→10→14→21→30 days. 📖 READ, SELECT, MAKE A CARD Open EPUB, PDF, TXT or Markdown in the built-in reader. Select any passage to translate it with AI, highlight it, or turn it into a card on the spot — no copying text into another app. Scanned pages get OCR (on-device recognition, with optional AI cleanup). Highlights, notes and reading progress are saved per book. 🎧 LISTENING CARDS Pair your own audio with SRT / VTT subtitles (or a text-based PDF, TXT, Markdown), or use the built-in graded ELLLO library. Pick a line and it becomes a card with the audio attached. Jump anywhere by typing a timecode: 95, 1:35 or 1:02:03. 📚 BOOK DISTILLATION BY AI Let AI distill a whole book into notes, minimal knowledge atoms, topic threads and a mind map — then turn it into flashcards. You also get a book-specific AI assistant you can chat with afterwards, plus a distillation log you can read or export. English books distill in English, Chinese books in Chinese. ✨ AI EVERYWHERE Generate skill trees from a single goal, translate text, explain words, generate card backs, clean up OCR text — using the AI provider you choose (DeepSeek, OpenAI, Gemini or OpenRouter) with your own API key, kept on your device and sent only to that provider. Not sure where to get a key? The in-app tutorial walks through each provider. 🔒 PRIVATE BY DEFAULT No account, no analytics. Your cards, books and notes stay on your device — delete the app, delete your data. Third parties: the AI provider you configure (only when you use AI) and Google AdMob for the free version's two banner ads (Today and Learn), which use your device's advertising ID — resettable or deletable in system settings. Premium (subscription or one-time) removes them. 📤 YOUR DATA STAYS YOURS Export decks as .cmdeck packs that keep your scheduling progress, or keep importing decks from Anki.