I pay £30 for my month’s water bill. My two flatmates each send me £10, to pay for their part. So, in reality, I only spent £10.
However, in the Summary section of the app, there’s no way for me to add the money from my flatmates to the expense of the water bill. So it still says I spent £30, and it will add this up to my monthly spending, which isn’t the case.
I was thinking of a feature where, for any given expense, I could click on its details page, and select an income that contributed to paying for this expense. In the case of my water bill, when I go to the bill’s details page, there could be a button which allows me to add the two incomes I got from my flatmates to this bill’s cost, effectively making it £10 for me and my budget.