Fuel Log: MPG & Cost Tracker

Fuel Log answers one question, asked standing at a pump with the nozzle back in
the holster: is this car drinking more than it used to?

The receipt in your pocket cannot tell you and neither can your memory, because
the answer is a ratio between two numbers nobody wrote down.

THE NUMBER IS NOT A PROPERTY OF A FILL-UP

It is a property of the distance BETWEEN two of them, and that fact is what this
app is built on. Type the odometer, the fuel and the price; the app works out how
far you went since the last full tank and how much fuel that took. Nothing is
stored, so correcting a reading you typed wrong in March corrects every figure
after it too.

IT SAYS WHEN IT CANNOT TELL YOU

The part almost every rival gets wrong, and the reason to use this one.

- The first tank you ever log has no figure: there is nothing to measure from.
You get that sentence, not a zero and not a dash that looks like a fault.
- Splashed in twenty litres to reach a cheaper pump? Mark it as a part fill.
Those litres still count towards your totals and towards the next full tank;
they are just not the end of a measurement, because nobody knows how full the
tank was.
- Forgot to log one? Say so. The app reports that stretch as unknown instead of
a number that is roughly half the truth with a completely plausible face.

An app that prints a figure for every one of those is guessing, in the same
typeface it uses for measurements.

LITRES, GALLONS, AND WHICH GALLON

The units belong to the VEHICLE, not to a settings screen, because a household can
have a car bought in litres per hundred kilometres and a bike its owner thinks
about in miles per gallon.

- L/100 km, km/L, MPG (US) or MPG (imperial): four ways of reading one ratio
- A US gallon is 3.785 litres and an imperial one is 4.546, twenty per cent
apart, so the app asks which you mean instead of printing MPG and hoping
- Change a unit whenever you like. It changes what you read and nothing else;
every number you have typed is kept exactly as you typed it

WHAT ELSE IS IN IT

As many vehicles as you keep. Every fill-up with its date, odometer, fuel, price
and a note. What each tank cost per litre, and what a hundred kilometres cost
you. Totals over thirty days, ninety days, a year or everything. A trend line
with real gaps for the months a vehicle sat still. A spreadsheet export with the
worked-out figures in it, and a backup file.

IT HAS NO OPINION ABOUT YOUR NUMBERS

No target, no score, and no colour that means good or bad. This app knows nothing
about your car, your route, the weather or the trailer you were towing, so every
judgement it could offer would be a guess wearing a uniform. It measures, it
arranges, and it says plainly when it cannot.

IT IS NOT A SERVICE LOG
No oil changes, no repairs, nothing due next. That is a different job, and this
app stays quick because it does not try to do it.

IT DOES NOT KNOW WHERE YOU ARE
No station finder, no price lookup, no route recording. The app asks for no
permission at all - not one - because there is nothing it needs to look up.

YOUR LOG STAYS ON YOUR PHONE

There is no account to make and no server to send anything to, and Google's own
cloud backup is switched off in the manifest as well - so the promise holds even
against the one upload nobody chooses. Take the app off the phone and the log
goes with it, so save a backup first: one file, and restoring it puts every
fill-up back.

A connection is used only to load adverts. Everything else works in flight mode.
No banner adverts either, so nothing sits on the screen while you are reading
your own numbers. Prefer none at all? One short video turns them off for a day.