This application is just a Japanese Mahjong scoring table.
You can switch the display of the scoring tables below by pushing the buttons.

・ Oya Ron (Dealer - from a discard)
・ Oya Tsumo (Dealer - from the wall)
・ Ko Ron (Non-dealer - from a discard)
・ Ko Tsumo (Non-dealer - from the wall)

Also, to understand how to calculate the score, you can turn off the "round-up mode", which does not dare round up to the tens place.