I just randomly found this:
https://www.jp.square-enix.com/denshadego/syodai/
A densha de go version by Square Enix that you can play in the browser (optimized for smartphones)
https://www.jp.square-enix.com/denshadego/syodai/
A densha de go version by Square Enix that you can play in the browser (optimized for smartphones)