We kept score on paper, on the bench. It is harder to write than it looks if you have not done it before, the wind turns the pages, and everything has to be copied into Excel afterwards to add up. The apps already out there did too much, and were awkward enough that nobody would open one just to look back at a game.
So I built the other thing: something anyone can fill in while the game is going on, and that adds itself up once it is over.