The apps

Core apps are what a trade runs on. Extra apps are what a business adds on top of them, and how many of each you get is set by the subscription each person holds.

What joins up, and what that means

Every trade app carries its own finance module — an overview, invoices, payments, expenses and a tax summary — and it stands on its own. A hotel or a shop can run the app it bought, raise an invoice and take the money, without adding Accounting to it.

Add Accounting, switch the crossing on for that app, and those screens stop being a second set of numbers: they become a read-only view of that app’s own slice of one ledger. This is the part worth being exact about. The apps do not send figures to each other and reconcile afterwards — they stop keeping separate figures at all. Two systems that sync can disagree; this cannot.

It is a choice, not a default. The crossing needs Accounting installed and the setting turned on, so a business that wants its till and its books kept apart keeps them apart.

Underneath, an invoice, a bill, a receipt and a payment are each declared once, in one place, and every app speaks that same shape. Money travels as a whole number of minor units with its own currency and its own precision attached — so a three-decimal dinar is a three-decimal dinar on every screen it passes through, rather than something a formatter has to guess at.