Add 50/30/20 widget

"50/30/20 Rule" is telling that all your money movements should have a distribution that's close to this one: 50% Needs, 30% Wants, 20% Savings

You already have Fixed and Variable expenses in your app, so you could count Needs as Fixed expenses, and Wants as Variable expenses. You could count Savings as a sum of incomes on all your Savings accounts.

This widget could be another chart on the Overview tab, or it could be a separate widget like Balance or Budget. It also could be a new Home Screen widget.