Stellar Hanafuda Koi‑Koi brings the classic Japanese card game to mobile in a calm and modern way. The rules stay true to the traditional game, and the presentation is designed to feel smooth, relaxing, and easy to enjoy. Whether you are learning Koi‑Koi for the first time or returning to a familiar favorite, this version gives you a clean and comfortable place to play.

Play Completely Offline
You can play anytime without an account or an internet connection. Everything works offline, so the game is always ready when you are.

No Ads. No Purchases. No Tracking.
Stellar Hanafuda Koi‑Koi is fully free.
There are no ads, no in‑app purchases, no data collection, and no tracking.
You get a simple and uninterrupted experience from start to finish.

Adaptive AI Opponent
The built‑in opponent learns how you play and adjusts its difficulty over time. If you prefer a steady challenge, you can also set a fixed difficulty whenever you like.

Optional Game Assistant
Turn on the Game Assistant if you'd like a hand — it suggests your best play and warns you when your opponent is close to scoring. It's entirely optional and off by default, so the game plays exactly as hands-on or as guided as you want.

Achievements
38 achievements to unlock as you play, from your first win to forming the rarest card combinations. Progress is tracked locally so it works fully offline, and syncs with Google Play Games to follow you across devices.

Accessibility Options
High Contrast Mode gives clearer visuals and reduced background textures for easier reading during fast rounds. Text size is adjustable across four levels, motion effects like falling petals can be turned off, and tooltips can be set to open with a tap instead of a hold. Vibration feedback can also be tuned to your preference or turned off entirely.