The Cash-flow Assistant answers the question "I have 3,000 CZK right now, what should I pay first?" You enter how much you have available and the app picks, from payments overdue or due within the next 7 days, the combination that makes the most sense to pay first.
Why not just by due date
The oldest debt isn't always the most important one. Debt advice services (StepChange in the UK, the CFPB in the US, and Czech advice centres too) agree: obligations should be ranked by what happens if you don't pay — not by interest rate, and not by how long the debt has been hanging around. Rent three months overdue can mean losing the lease without notice; utilities face disconnection after a written warning; unpaid child support becomes a criminal offence after four months. A streaming subscription past its due date, by contrast, causes nothing dramatic.
How the app calculates
Every payment gets a category (rent, utilities, insurance, child support, installment, telco, subscription…) that you set in the payment form. The category determines a weight based on the typical consequence of being late, and the app combines it with how close the payment is to the threshold where the consequence actually kicks in (3 months for rent, roughly 30 days for utilities). That produces a ranking — and the app then picks the combination of payments that fits within the balance you entered and covers as much of what matters most as possible.
For payments that don't fit within the balance, the app also shows the typical consequence of being late — not to scare you, but so it's clear what the decision is about.
What the app doesn't do
This isn't individual financial or legal advice — just information about typical consequences based on publicly available sources. The app also doesn't know about your personal arrangements with creditors (a deferral, a payment plan) — if you've agreed on something, follow that, not the order in the app.