Write down what the scale said. It draws the line.

It is one number a week

Stand on the scale, type what it said, and that is the whole of it. From the second reading on there is a line, and the number at the top is the total since you started — not this week’s.

That is deliberate. Week to week is noise: water, salt, the time of day, a big dinner on Friday. A good week can follow a bad one with nothing having actually changed, and an app that leads with the noise makes the signal hard to see.

A week that goes the wrong way is just a week

Look at weeks four, seven, eleven and fifteen on the chart above. That is what these lines really do, and BodyPal says so plainly — in amber, not red.

Red means something is wrong. Four hundred grams is not something going wrong, and an app that flashes red at you for telling it the truth is one you stop telling the truth to.

It never congratulates you either. There are no streaks, no badges and no best week ever — just the number you gave it and the line it makes.

It does not assume you are losing

Plenty of people are working the other way: recovering from an illness or an operation, building up after treatment, or simply told to put weight on. Others are holding steady after a programme has ended, which is the longest stretch of all.

So the direction is a setting — less, more or steady — and it decides which way counts as the way you are going. On steady, neither direction is treated as the good one and every change is shown in plain ink.

BodyPal only records what you tell it. If you are working with a doctor or dietitian, their plan is the one that counts — this just keeps the numbers so you both have them.

What else it keeps

• The dose, if there is one For medication prescribed as part of a weight-management programme, under medical supervision. Recorded from the day it starts — a future date is fine — and marked on the chart, so a change in the line has its explanation beside it.
• A note against any weigh-in “Away all week.” “Start of a cold.” It turns an unexplained bump in November into an explained one.
• A copy you can keep One file, saved wherever you like. Everything living on your phone is the point, and it is also the risk: a lost phone is a lost record unless you have a copy.

Where your readings go

Nowhere. There is no account, no sign-up and no server holding your weight — the readings are stored by the browser on your own phone, and nothing is uploaded.

The one exception, stated because a privacy claim that is almost true is worse than none: once a day the app sends a single word saying it was opened, so we know whether anyone uses it. Once a day rather than once an open, which is what stops it being a record of when you weigh yourself. Nothing about you, and nothing off the readings.

Keep it on your home screen

Open it, then use your browser’s menu — Install app on Android, Add to Home Screen from the share button on an iPhone. It then opens like any other app and works with no signal.