Solve discard problems and train your Riichi Mahjong skills.
Mahjong Solo Issou helps you learn tile efficiency by comparing all possible winning tiles.
Practice logical discard decisions and reach tenpai faster with every hand.

Main Features
- Rich set of practice problems: Tackle scenarios that test your thinking in practical situations.
- Detailed explanations: Learn why a discard is optimal with clear winning-tile breakdowns. Improve through logic, not intuition.
- Always-visible shanten count: Let the app handle the tricky calculations so you can focus on choosing the right tile.
- Win Rate Display: Win rates can be displayed as reference information for hand changes.
- Analysis tools: Track and visualize your tenpai rate and average turn count to see your growth through data.
- Replay training: Reattempt any problem from your history to overcome weak patterns.
- Offline support: Practice anytime, anywhere, without worrying about data usage.

About “Tile Efficiency” in This App

In this app, tile efficiency is defined as choosing discards that advance shanten in the shortest possible path toward tenpai.
Therefore, strategies such as intentionally breaking tenpai for a better wait (shanten back), or considering yaku/dora for higher points, are not included.
The goal is to help you master the pure fundamentals first.

Recommended For
- Beginners who don’t know what to discard
- Players who have relied on intuition but want to improve logically
- Anyone who wants a solid foundation in tile-efficiency concepts
- People who want efficient training during commutes or small breaks

Daily practice will make your Mahjong stronger—and more fun.
Start building your best Mahjong mind today!