Saved before it is sent
The capture lands on the phone the moment you press Record. Sending is the queue's problem, and it keeps trying without the application being open.
Works with or without signal
Record the expense the moment it happens.
Capture what you paid while you are still at the counter. It is saved on the phone the moment you press Record, and it goes up on its own when the connection returns.
Access to a client is granted by an administrator.
Built around the moment
of the expense.
Everything follows from one fact: the record has to be made where the money is spent, and not that night in front of a computer, when the receipt is already lost.
Three figures, not one
What you paid, what it is worth at the reference rate of that day, and what the bank finally charged. Each one is kept, and none of them replaces another.
The receipt travels with it
Photograph the ticket at the counter. The image is queued beside the movement and stays attached to it, so the evidence is not a separate chore.
One client, one set of books
Which client you are working in is enforced by the database itself and not by the screen. A mistake in the application cannot show one client's movements to another.