While there currently isn't a dedicated Google budget app, Google Sheets plus Tiller provide a budgeting solution more powerful and flexible than any app.
The Monthly Budget Calendar is a minimalist spending tracker and monthly budget for Microsoft Excel and Google Sheets. Set your monthly target, track your daily spending, and know what's available until the end of the month.
At first, budgeting seems scary, like it's taking away your freedom. In reality, the reverse is true. Better yet, it’s surprisingly simple to make budgeting work for you.