HOME / HOW BURN WORKS

One tap when you stop eating. Burn handles the rest.

There is no food diary, no barcode scanner, and no daily calculation. You start the timer when your last meal ends and Burn tracks the fast from there, naming each stage as you reach it.

Here is the whole loop, from the tap that starts a fast to the report that reads your month back to you.

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You start it

One tap when your last meal ends, or set the time it actually finished.

It names each stage

Nine of them, from Fed State onward, with a buzz on your wrist as you cross.

It helps when it is hard

Six tools one tap away, for the twenty minutes that decide a fast.

It reads your record back

Insights, Journal, and a Morning Brief written from your own numbers.

The loop

Four moments, every fast.

Two of them take a single tap. The other two happen while you get on with your day.

01 START

Tap when you finish eating

Start now, or backdate it to when you actually stopped. Forgot last night? Set the real time and your record stays accurate.

Name the fast if you want to, so patterns like "push day" show up later in your history.

Burn's Begin Your Fast sheet with Start Now and Custom Time options

02 DURING

Watch the stages arrive

The ring counts up and a progress strip shows the stage you are in against the ones ahead. Cross a boundary and Burn tells you, on your phone or your wrist.

Log energy, water, training and how your gut feels in a couple of taps. All optional, and all useful later.

Burn's fast screen showing stage progress to 24h, the Morning Brief card, and energy, water, training and gut check-ins

03 FINISH

Close it out and see what you did

End the fast and Burn gives you the total, the deepest stage you reached, and how much effort it took. Then a note on how to break it well.

A short reflection afterwards, if you want to record how it felt.

Burn's Fast Complete screen showing 1d 2h, Fat Burning reached, 26.1 hours and Major effort

04 AFTER

It all lands in your record

Every fast joins your Journal by day, week and month, alongside your check-ins, weight and anything you have shared from Apple Health.

Which is where the patterns start coming from.

Burn's Journal tab with the Days view selected, showing an August 2026 calendar of logged fasts, today's ring reading 44, a fast in progress at 1d 2h, and a day total of 1d 18h

The app, in four tabs

Each tab answers one question.

You will spend most of your time on the first one.

Burn

WHAT IS HAPPENING NOW

The live timer, your stage, today's check-ins, and the support tools when you need them.

Journal

WHAT YOU HAVE DONE

Fasts, notes, water, electrolytes, measurements, check-ins and Apple Health data, by day, week or month.

Insights

WHAT IT MEANS

Morning Brief, your patterns, headline stats, averages, personal records and challenges.

Profile

EVERYTHING ELSE

Fasting settings, notifications, Apple Health, subscription, and your data export.

The rhythm

Burn gets more useful the longer you use it.

DURING A FAST

Stage crossings, a buzz on your wrist, the stage detail if you want to read it, and the support tools when the hunger lands.

EVERY DAY

Morning Brief when you wake, start the fast, quick check-ins, your live Body Score, then the finish and a reflection.

EVERY WEEK

A weekly summary, new patterns as they emerge, and progress on any challenge you have running.

EVERY MONTH

A monthly review, milestones and records, program completion, and a recommendation for what to do next.

Patterns need history to work from, so Burn starts surfacing them once you have 14 completed fasts behind you.

Burn's Insights tab with the Morning Brief, a power day insight, and stat tiles for total fasts, longest fast and streaks

Burn's Journal in Weeks view, with the week of August 10 to 16 expanded: 4d 5h fasted, 6 fasts, 16h 54m average, 19h 54m longest, 100 percent rate

What you never have to do

•Count a calorie or weigh a portion
•Photograph or scan your food
•Fill in a macro grid
•Share health data you would rather keep to yourself
•Give up your history if you leave, since you can export all of it to CSV

What Burn works from

One number: how long it has been since you last ate. Everything else on the screen is built on top of that, plus whatever you choose to add.

Connect Apple Health and sleep, steps and heart rate join in as context. Leave it disconnected and the fasting side works exactly the same.

Burn names the stage that your elapsed time falls into. It does not measure ketones or anything else inside a cell, and it says so on every stage screen.