i've been doing it for almost four years now, and it's amazing to see how wrong and how frequently wrong your preconceptions and expectations can be.

you don't need an app to do that though. a spreadsheet is perfect for that purpose (and telling Google Assistant to 'flip a coin' or 'give me a random number between 1 and 20') and gives unlimited flexibility and less reliance on developer to implement features you want. not a lot of people appreciate this, but sometimes trying to accomplish a task with the general-purpose tools you have at hand can lead you to discover solutions so good it is in fact superior to any dedicated tool.