Over 450K Players and the largest Internet base Mahjong Game. They have a Dan System to move up to higher level tables. The top rank is Tenhoui. Recently, some Tenhoui players have become professional players. It is seen as a path for strong players.
Yes, but only to play on the Houou (highest ranked) table
JPN / ENG and many others
This game is for mobile devices and requires a one-time payment. You can play against AI. This is recommended for new players for practice.
One time purchase for $3.99
JPN / ENG
Flash game for PC. This game is totally free to play, but is only against AI. Recommended for new players to get used to the game and review yaku and game flow.
SEGA MJ is very popular game and interesting part is you can play on your PC or smart phones against players are playing in Arcade game store in Japan. They host event with Pro Players and Saki from Anime. They use commentary voice from real Mahjong TV commentators as well.
This is very new Riichi Mahjong game and language is in Chinese. However, Developer is trying in English. The graphic and game itself looks fine and could be popular in the English community.
Not for now
Maru-Jan runs very big Online tournament with cash pries once a year. They have tried to make this game like playing in real Auto Table. And also, they do run YouTube channel and written contents for helping players get improved.
真雀龍門/ Shin Janryumon
Janryu mon also using their 3D graphics and many effects. And if they lost all the money in game, you need to purchase to keep play this game.
ジャンナビ / Jan Navi
Jan Navi has good graphics. It is needs to pay for games however, there are system that you can play with Pro Players. You can play with PC, MAC, iOS, and Smartphones and tablets.
Flush game for PC. This game only use word Ron Tsumo Pass so it is very easy even in Japanese. Use only bamboo for Chinitsu Mahjong. Very good practice for everyone who is not good at complex shape. Recommend to play.