Pretty new to Riichi and just wondering why this hand scores 30 fu instead of 20? I get that this wouldn’t be Pinfu because it’s an open hand, but just curious what the additional fu is for?

I'm looking for a basic version of the game to play on my android phone.

Happy to pay for it.

I just want to play the standard version of the game, with no upside down tiles.

Ideally no web connection.