Vimal's Taxi Fuel Pool

Ten drivers at one stand share diesel money, so the app records who filled the tank, divides it fairly, and shows each man his own number.

Who this is for

Vimal Rathod parks sixth from the left at the taxi stand outside Ratlam junction. Ten drivers, one shared diesel arrangement, three cars usually out on long runs. It is quarter past six in the morning, the vegetable mandi behind the stand is in full cry, and Vimal has just put 2,400 rupees of diesel into two cars. He is holding the receipt in his teeth while a passenger loads bags into the boot. By evening he will not remember which two cars.

How the job is done today

There is a long notebook above Vimal's dashboard with dates, amounts and names written sideways. There is also a WhatsApp group called Stand 10 where bills get photographed and then buried under morning greetings and forwards. Some men write in the notebook, some only send the photo, two do neither and tell Vimal in passing. On the first of the month everybody gathers near the chai stall and works it out by shouting, and the man with the loudest voice usually pays a little less than he should. Twice this year a page tore out and nobody could prove anything.

The screens, in order

1. What you owe — The screen that opens first, so a driver knows his own number without asking anyone or reading anything long.
2. I filled the tank — For the man standing at the pump with the receipt still warm, to put in the amount and tick whose cars ran on it.
3. This month's fills — For anyone who doubts a figure and wants to see every fill, who paid for it, and how it was divided.
4. Settle up — For the man handing over cash or sending UPI at the stand, to say how much he is paying and to whom.
5. Money received — For the man being paid, so nothing is counted as settled until he himself has confirmed it.

What it keeps track of

• Fills — who paid, how much, which day, which pump, which drivers it was shared between, photo of the receipt
• Drivers in the pool — name, car number, phone number, in the pool or stepped out
• Payments — who paid, who received, how much, which day, cash or UPI, confirmed by the receiver or still waiting

The one decision that matters

Either the app chases men with notifications when their share crosses a limit, or it carries no alerts at all and puts the whole answer on the screen the moment the app opens. The stand sits behind a vegetable mandi. Nobody hears a phone there, and a driver checking his phone at a signal has four seconds. Go with no alerts. One screen, one large number, in rupees, at the top: what you owe and to whom. Everything else sits below it. A notification that goes unheard is worse than none, because Vimal will believe the man was told.

What to leave out of the first version

Leave out splitting by kilometres run. It is the fairest way and it is the reason the app never gets used, because it needs meter readings from ten men who will not give them. Divide equally between whoever the payer ticks for that fill. Also leave out taking payment inside the app. They already pay each other by UPI while standing two feet apart. The app only has to remember that it happened.

How you would know it worked

On the first of next month nobody gathers at the chai stall to argue. Three drivers pay Vimal before the morning airport run, each taps it off on his own phone, and the notebook above the dashboard stays shut all day.

Build it

Paste this in and let it run.

Ten of us at the Ratlam taxi stand share diesel money. Whoever has cash fills the tank and the others owe him. Build me a phone app where the man who fills puts in the amount and the date, ticks which drivers ran on that diesel, and the app divides it between them and adds it to what each one owes him. When any of us opens the app the first thing on the screen should be one big number in rupees, what I owe and to whom, and under it what others owe me. When someone pays me by UPI at the stand I tap his name and mark it received, and he sees it cleared on his side. It must all work by looking, not by sound, because the mandi is right behind us and no one hears a phone. Hindi and English both, and big enough to read in sunlight.