AI Go King lets you play Go against AI, replay professional games, and solve tsumego (life-and-death problems) in one app.

■ On-device AI — play offline
• The open-source Go AI KataGo runs directly on your phone. Play a game on a plane or on the subway, no internet needed.
• Three AI models: Fast, Standard and Strong. Fast is built in; Standard and Strong can be downloaded in Settings.
• Choose the AI thinking time. The longer it thinks, the stronger it plays.
• When the game is clearly lost, the AI resigns.

■ Cloud AI — from 18 kyu to 9 dan
• Pick your opponent's rank: 18k, 15k, 12k, 9k, 6k, 3k, 1k, 1d, 3d, 5d, 7d or 9d.
• With "Play like a human" on, the AI plays like a person of that rank.
• Turn it off to face the Strongest AI, which plays at full strength.
• Check the position at a glance with the live win rate.

■ 1:1 with a friend
• Take turns on a single phone.

■ Game settings
• Board size 9×9, 13×13 or 19×19
• Even game or 2–9 stone handicap, choice of komi
• Korean, Japanese or Chinese rules
• Time limit of 5, 10, 20 or 30 minutes, or unlimited
• Play Black or White and name your game

■ In-game help
• Hint: see the move the AI recommends.
• Undo: 3 per game. After that, watch a short ad to undo once more.
• Confirm moves: tap again to place a stone, so no more misclicks.
• Scoring: when the game ends, the AI counts the territory and shows the result.
• Games are saved automatically. Branch off from any position with "New game from here".

■ Pro game records
• Browse the latest professional games and search by tournament or player.
• Step through move by move, jump 5 moves, or use auto play.
• For records with AI analysis, see Black's and White's win rate at every move.
• Continue any position against the AI.

■ Tsumego
• Train your reading with Beginner, Intermediate and Advanced problem sets.
• Solve by placing stones on the board. Your accuracy and history are saved.

■ Languages
English, 한국어, 日本語, 简体中文, 繁體中文

This app uses the open-source Go engine KataGo (MIT License).