From Soluna Interactive

Learn Japanese,
one card at a time.

A spaced-repetition flashcard app built for Japanese learners. JLPT decks from N5 to N1, native audio, and a study system that adapts to how you learn.

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Study

Spaced repetition that actually works.

Cleo uses FSRS scheduling to show you the right card at the right time. Rate each card and the algorithm adapts to your memory — so you spend less time on what you know and more on what you don't.

Cleo review session showing a kanji flashcard with grading buttons.

Listen

Hear every word spoken natively.

Every card comes with generated Japanese and English audio. Tap to hear pronunciation, or use the audio loop for passive immersion while you go about your day.

Cleo audio loop screen for immersive listening practice.

Build

Your decks, your way.

Start with curated JLPT decks from N5 to N1 — kanji and vocabulary. Or create your own cards with built-in dictionary autocomplete that fills in readings, meanings, and examples for you.

Cleo deck browser showing JLPT-organized kanji and vocabulary decks.

How it works

Simple tools for serious study.

Pick a deck. Review your cards. Let the algorithm handle the rest.

FSRS scheduling

The same algorithm behind Anki's latest update. Cards surface exactly when your memory needs a refresh.

JLPT N5–N1

Ten preloaded decks covering kanji and vocabulary for every JLPT level. Start wherever you are.

Sync across devices

Your decks, cards, and progress sync through your account. Pick up on any device exactly where you left off.

Native audio

Every card has spoken Japanese and English generated by Google Cloud TTS. No robotic voices — natural pronunciation you can trust.

Your data

We collect only what the app needs to work.

Cleo stores your account and study data on Supabase so your progress syncs across devices. That's it — no ads, no analytics, no tracking.

✓ Account email and hashed password — we never see your password in plain text
✓ Study data synced via Supabase — decks, cards, and review history
✓ Audio generated by Google Cloud TTS — card text only, not personal data
✓ No advertising, no third-party analytics, no tracking SDKs
✓ Delete your account and all data anytime from within the app

Your Japanese,
one card at a time.

JLPT decks from N5 to N1. Spaced repetition that adapts. Audio you can trust. Start studying today.

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