Mahjong Coach
A single-player Mahjong game and learning coach for Apple platforms — and the first app to speak MJPF.
iOS · SwiftUI offline-first
Mahjong Coach is built like a fitness app for your Mahjong: play against tiered AI opponents, get a coach that explains every suggestion, and watch a Master Score climb as you learn. The deal-sharing in the app is powered by MJPF — which is why we published the format openly.
What it does
Play & learn
Two modes — a coached training table and a graded "let's play." Five rule sets (Hong Kong, Riichi, Chinese Official/MCR, Taiwanese 16, Simplified).
A real coach
Ranked considerations, a Hide/Show toggle, a "Why?" deep-dive, and post-game analysis that paraphrases itself so it never reads like a form letter.
Tiered AI
Basic → Moderate → Very Good → Mahjong Wizard. Efficiency, defense (push/fold, suji, genbutsu), and tile-counting scale with the tier.
Solitaire too
A full layered tile-matching Solitaire with guaranteed-solvable deals, its own coach, and its own Master Score.
Progress & streaks
XP, daily/weekly/monthly streaks, charts you can drill into, a Master Score out of 10,000 that decays if you stop playing.
Compete with MJPF
Share a deal as a QR code or a copyable code. A friend plays the exact same hand on any device and you compare scores — no server involved.
Compete without a backend
In the app, Challenge a Friend turns the deal you're about to play into an MJPF document and shows a QR code (and a copyable code). Your friend scans or pastes it, plays the identical wall, and the app compares results. Nothing leaves the device except a tiny code you chose to share. That's the whole point of MJPF — and Mahjong Coach is the reference for how it feels in practice.
Privacy: Mahjong Coach is offline-first. The only network feature is a user-triggered diagnostics send. MJPF documents carry game data only — never accounts, contacts, or device ids.
Status
Mahjong Coach is in active development. Availability, pricing, and store links are managed by the project owner; this page is a teaser for the app that motivated the MJPF format. If you're building a Mahjong app, the format is yours to implement — interoperate freely.