Cauri

The mobile money booth ledger, on the phone, even with no network.

Type: Installable offline web app
Year: 2026
Role: Product thinking, design and development
Open the tool: Open the tool (new tab)

The day screen: expected cash and balance for each network (sample data)

A withdrawal in detail, with its tracked change: 4,000 F corrected to 40,000 F

Evening closing: every network matches, 2,000 F is missing from the cash drawer

Act I

The real problem

In a mobile money booth, every deposit and every withdrawal goes into a notebook.

The clerk writes down the time, the network, the amount and the customer's number. At night, he adds it all up by hand and compares it with what is left: the e-money balance of each network (MTN, Moov, Celtiis) and the cash in the drawer. When the two don't match, nobody knows where the mistake is: a forgotten line, a crossed-out figure, a wrong sum.

The manager is not always there. She finds the gaps late, with no way to explain them.

Act II

The tool I built

An app installed from the browser that works with no network. It replaces the notebook, not the habits.

01
Fast entry
Deposit or withdrawal, network, amount, customer's number. Designed to take under 10 seconds.
02
100% offline
Everything stays on the phone. No account, no password, no server.
03
Every gap explained
At night, the app compares what should be left with what is left. Each gap is written in plain words and unfolds to show the calculation.
04
The daily summary on WhatsApp
A summary goes to the manager, without a single customer's number.