Every tool in the app, and why it is built the way it is.

Choose what you are working on, and the app arranges itself around it.

A Playbook is your declared focus. Pick one, and Home leads with the measures that matter for it, Meals carries its targets, and the app tells you what it gives its best with. One is active at a time, and you can switch whenever you like. It never changes how anything is measured.

Six Playbooks

• Longevity. The default: fitness, heart rate and recovery, vascular and metabolic age, and glucose. For anyone with a wearable that records their nights.
• Weight Loss. Trend weight and the daily energy target in front, with the Weight Loss Planner one tap away.
• Minimal Viable Health Habits. For when you have turned things around and want to hold what you have built. It keeps the markers that slip first in view: muscle, visceral fat, fitness, resting heart rate, overnight HRV, glucose, blood pressure and sick days.
• Metabolic Health. Glucose stability first: a CGM month, fasting glucose and the CGM's HbA1c estimate, then visceral fat, adiposity and blood pressure.
• Keto Diet. Ketones, fasting glucose and the glucose–ketone index, with carbs, fat and protein in front.
• Essential. The starting point when there is no wearable yet: a scale, a CGM, or a device that writes very little. It works with what you have and puts your devices on Home.

What changes on Home. Home shows up to nine cards, in your Playbook's order; Longevity, the default, keeps the Home you know. On the others, a card that has nothing yet says what it needs in one sentence, with a button that takes you there: Weigh in, Start a CGM, Log a meal. Except on Essential, a third page in the top carousel, Also tracked, keeps nine more measures one swipe away, because a focus should narrow your attention, not your data. Every card opens the same full chart it always did.

Each Playbook also says what it gives its best with: a smart scale, daily meal tracking, a CGM month, a blood-pressure reading a month. Each item is marked In place or Not yet, You have this or Helps where it is optional, and Coming soon where VT is still building it. On every Playbook but Longevity, a slim strip on Home lists what is missing, each item one tap from its fix. If you know and would rather not be reminded, choose Snooze 30 days or I know, leave it. Reminders are few and gentle, and they describe what is missing rather than scoring you on it.

Fifty measures, each read against your own normal.

Vitality Tracker charts 50 biomarkers across cardio, respiratory, activity, energy, nutrition, vascular, metabolic, glucose, body composition and sleep. Every one opens the same way: its value; its chart over a month, three months, a year or any range you choose; where it sits in your own baseline; and a short explanation of what it is and why it matters.

Home, at a glance. Your Vitality Score sits at the top: 0–100 across five domains, with a line naming the one to focus on. Capacity and Sleep sit below it. A second page holds body composition, the day's energy against your goal, and live heart rate, SpO₂ and active calories. Below, every card carries a small rail showing where today sits in your own band.

Your normal is the reference. Every card on Home reads today against your own 30-day range, so "high" means high for you. Each chart shows your own band where your history defines normal, and a published range where one exists, for example:

• SpO₂ 95–100%;
• BMI 18.5–24.9;
• fasting glucose 3.9–5.5 mmol/L;
• body fat by sex and age.

Sleep, scored two ways.

• The Sleep Quality score is built from six parts: duration, efficiency, continuity, how long you took to fall asleep, regularity and physiology. It names any part your device cannot supply.
• The Sleep Health Index reads 28 nights, with regularity weighted most.
• Regularity is the Sleep Regularity Index. A missing night counts as unknown, never as awake.
• Your sleep need is learned from the mornings you wake on your own, without an alarm, so a habit of short nights cannot set its own target. Until there are five such mornings, it is estimated from your recent nights and labeled as a habit.

Capacity: how much you can take on today. Three rings: your autonomic system (HRV and resting heart rate), your sleep, and how you feel. A sentence names the main limiter. Six measures sit beside it against your baseline, and each day keeps the value it was given.

Body composition, honestly corrected.

• Trend weight smooths out the day-to-day noise.
• Body fat is corrected by your latest DEXA scan.
• A five-segment body map comes from scales that measure each limb.
• Each scale's visceral fat index is kept as its own series.
• The Weight view adds lean mass, ideal weight and maximum muscular potential.
• One tap gives a one-page PDF.

Ages that mean something. Metabolic age is S-AnthropoAge (Fermín-Martínez et al., Aging Cell, 2023), from your body measures. Vascular age comes from a measured pulse wave velocity, or is estimated from a cuff reading when that is all you have.

Enter anything by hand. Log Manually covers 12 markers: weight and body fat; blood pressure, up to three readings, the first discarded when you enter three and the other two used; glucose, ketones and Lumen; sickness, bowel movements and your period; alcohol, nutrition and hydration. Hand entries sit beside synced ones, with their source shown.

Thirty seconds that make every other number make sense.

Six sliders, once a day: fatigue and vigor, perceived stress, body discomfort, satiety and food noise. Four follow established scales: the fatigue and vigor subscales of the Profile of Mood States, 0–20; the four-item Perceived Stress Scale, 0–16; a 0–100 visual analog scale for satiety. Body discomfort and food noise are rated 0–10.

Your answers become measures in their own right, charted like any device signal, and context for everything else you record. Capacity's "how you feel" ring is built from fatigue, vigor, stress and body discomfort, each read against your own baseline. A blank stays blank, so zero is always an answer you gave.

Each morning, before any score appears, the app asks one question: how did you sleep? It is the sleep-quality item of the Consensus Sleep Diary. Your own judgment is recorded before a number can color it.

Your night, recorded by you, laid over what your device saw.

Turn on Night Log and choose your night window. Opening the app during that window goes straight to a near-black screen in warm amber, with no blue light and no clock unless you want one. Tap In bed, Awake, Toilet break, Back in bed or Up for the day, without properly waking. A tap registers the moment you touch, and a mistaken tap can be undone for 45 seconds. Left alone, the screen dims further and covers the buttons, so the first touch only wakes it and nothing is logged by accident.

In the morning your taps sit as amber columns over your device's sleep stages, showing which wakings it caught and which it missed. A waking you forgot to close is closed with a sensible estimate, and every event can be edited. If you tapped Up for the day well after your device says the night ended, the sleep score is marked low-confidence instead of being trusted. With a Polar H10 chest strap, In bed starts an overnight recording.

A quiet nudge when part of your picture is going stale.

Some measures need refreshing on their own schedule, and VT keeps track. When one is due, a message says so and says why: a blood-pressure check; a new waist measurement after your weight has shifted; a fresh CGM month; an HbA1c re-test. Each arrives in System Messages with its reason and the date it fell due.

Other reminders guard against the things that silently break a record.

• Your watch. On iPhone, a 7 pm reminder to check its battery, and around 9 pm a "Wearing your watch tonight?" when Apple Health has had no heart rate for an hour.
• Your CGM. A sensor's expiry, 12 hours ahead.
• Syncing. A "syncing has paused" notice if the app has not run for two hours.
• Your plans. Supplement reminders on the days something is due, and your Weight Loss plan's weekly review.

Plan the week, log the day, and know how far to trust each number.

Meals is a planner first. Your day is laid out in slots: breakfast, lunch, dinner and snacks; first meal and last meal; or one meal. Planned items wait for a tick when you eat them. The week ahead can be copied, saved as a template, analyzed day by day before you shop, and turned into a shopping list.

Logging, every way you eat.

• Recents. Log your last amount in one tap, or hold to adjust.
• Search. 18,070 reference foods from USDA, New Zealand FOODfiles and the Australian Food Composition Database, each with its source shown.
• Scan. Your own foods first, then VT's, then Open Food Facts. When a barcode is unknown, photograph the nutrition panel and check what was read.
• Describe. Say what you had in your own words.
• Photograph the plate. Add the menu if you are eating out, answer a few questions in hand-sized portions (a fist, a palm, a thumb), and the meal is logged item by item. Where the restaurant publishes its figures, you choose between theirs and the estimate.

The photo's own time becomes the meal time. The image is resized, stripped of its location and metadata, used once and never stored.

Recipes that know what is in the pot.

• Recipes come in three kinds: cooked in batches, assembled, or a single serving.
• Paste a link or photograph a recipe for a draft you can check.
• When you cook, weigh the pot. Nutrition follows the cooked weight, so evaporation is accounted for, and VT learns your yield from your own weighings.
• A pot shows how much is left and how many days it keeps, and asks once they have passed.

Quality you can see. Everything carries its NOVA processing class; a glycemic index (measured values from the 2021 international tables for 2,822 foods, every other value labeled as an estimate); and glycemic load, shown for a day only when the GI is known for at least half of that day's carbohydrate.

Confidence grades, A to G. Every entry is graded on how it was made, not on how healthy the food is: a weighed batch of well-documented ingredients is an A; a barcode product logged by its pack a B; a photo an F; a description a G. Weigh it on a scale and the grade goes up. The day's badge appears only when the day's data deserves a second look.

Analysis that describes, never judges. For any day or week, the Analysis covers energy and macros; vegetable, fruit and fermented servings; glycemic load and dietary GI; NOVA classes; energy density; fats, sugar and fiber, sodium and potassium; alcohol and caffeine; meal timing; hydration; plant and animal sources; and the quality of the data itself. It compares you only with your own last week and four-week average. Tap any segment to see the foods behind it.

Photo logging, describing a meal and recipe import use Eir analysis. Meet Eir →

The plan you made becomes the food in your kitchen.

One tap turns the week's plan into a shopping list: grouped by shop section; quantities taken from what you planned, in grams and in packs ("2 × 400 g can · 800 g"); each line saying which recipe it is for. Plan two servings of a recipe and its lines double.

Tick as you shop. Mark Have for what is already in the pantry, move a line to another section, remove it, or add your own. Change the plan and regenerate: your ticks, Have marks and removed lines survive.

One tap to start, one to stop, and a record that knows a gap from a fast.

Choose a rhythm, 12:12, 14:10, 16:8, 18:6 or your own, or simply track. The ring shows your fast, with milestones you can tap to read about: glucose stabilizing, fat burning, ketosis, autophagy. The milestones are general estimates and are labeled as such. Run past your plan and the ring shows the time over, rather than a countdown stuck at zero.

Cards tell you when you can start eating and when your next fast begins. History shows every fast from a month to a year, against a 14–18 hour band, with the day's meal times one tap away. If you seem to have forgotten, a banner asks, about an hour after your usual last meal.

The timer and your meals agree.

• Log a meal during a fast and VT asks whether to end the fast at that time.
• Black coffee, tea and water do not break a fast.
• An eating window that crosses midnight stays on the day it started.

See what your food does to you, then compare it.

Wear a continuous glucose monitor and Vitality Tracker draws your day on the glucose line. Meals, drinks, fasts, training, protocols and waking each become a marker you can tap. The Live Dashboard reaches back through your whole history. Comparisons puts two or three meals side by side, on one chart, so you can see which breakfast suits you.

The Live Dashboard. The trace scrolls back through every day you have worn a sensor: recent days at full detail; older days at five-minute, then fifteen-minute resolution; never hourly, which would shave the top off a real peak.

The markers along the top tell the story of the day:

• Meals. Each is named by its slot, with carbs, sugar, glycemic index and fiber. A meal of several items gets a bar along the foot of the chart, for example "Carbs: 62 g • GL: 28".
• First and last meal. With the fast before and the eating window.
• Waking. With your sleep score.
• Training. With its effort.
• Protocols. Sauna, cold, breathwork and the rest, each with its own icon.
• Drinks and your own notes. Log anything, in your own words.

The colors are deliberately strict: green is 3.5–6.5 mmol/L, a healthy person's band, not the wider clinical range.

The statistics are the ones clinicians use, each named and each with an explainer. Over 90 days: GMI (Bergenstal 2018), estimated HbA1c (Nathan 2008), time in range (3.9–10), time in tight range (3.9–7.8), time below and above, and sensor coverage. For the day on screen: mean, SD and coefficient of variation, fasting and overnight means, highest and lowest with their times, MAGE and LAGE. A figure turns green only when it meets the international consensus target. The Day list and the Report summarize the current sensor: each day's mean and time in range, and for the session, average variability against the ≤36% target, GMI and a stacked time-in-ranges bar.

Comparisons: your breakfast, your curve. The same plate of food can do very different things to different people. The only way to know what it does to you is to see your own curves side by side. That is what Comparisons is for.

How it works

• Pick from your log. Choose from the meals you logged in Meals over the last 14 days, or any range you set. Pick whole meals or single foods, and set a meal against a single food.
• Meals are counted the way you eat. Everything in your breakfast slot is one breakfast. Items more than an hour apart become two meals. Your first meal of the day can start at the moment you ended your fast.
• Up to three at once. Meals A, B and C each get their own color on one chart. Each is drawn from your first bite to three hours later, at 15-minute points.

Three numbers for each meal, each chosen for a reason

• Peak rise. How far above your pre-meal level the meal took you, with the peak itself. Green, amber above 6.5 mmol/L, red above 10.
• Two-hour exposure. The area of the curve above where you started, over two hours. It is the most robust single number for ranking meals against each other.
• The dip. Whether you fell below your starting point between 90 minutes and three hours after eating, and when. This reactive dip is the pattern behind post-meal hunger and the mid-morning slump, the crash that sends you looking for the next snack. In 1,070 adults wearing sensors, the dip two to three hours after a meal went with more hunger, a shorter wait to the next meal and more eaten across the day (Wyatt 2021).

An example (synthetic)

Same person, same week. The oats gave nearly four times the two-hour exposure, and two and a half hours later a dip below where she started.

Then experiment: the same breakfast with a ten-minute walk after it; protein first, then carbs; basmati against jasmine rice; dinner at 6 pm against dinner at 9. Each meal you log is a comparison waiting to be made.

Honest by design

• No guessed lines. A curve uses only readings close enough to trust, and no line is drawn across a gap.
• Partial windows are marked. Less than three hours of data is labeled "partial".
• Nothing hidden. A meal without sensor data stays in the list, grayed, rather than vanishing as if it was never eaten.
• Not a single-food verdict. Comparisons shows what happened, side by side. A curve includes everything you ate around that time, so it does not claim a single food caused it.

Sensors and notifications.

• Starting a sensor. Note where it is worn (seven sites) and a warm-up clock counts down until the readings can be trusted: an hour for Libre and GS3, 30 minutes for Ottai.
• Sensor care. You get a reminder 12 hours before the sensor expires. Libre and GS3 report a new sensor themselves; for Ottai and other Nightscout uploaders, VT asks "Did you change your sensor?" after a gap in readings, so each sensor keeps its own record.
• A high-glucose notification. It arrives after 15 minutes above your threshold (7.8 mmol/L unless you change it), and again if you are still above it two hours later. You can switch it off.
• Lows. Your sensor's own app remains the right place for low alarms, and VT says so.
• Implausible readings. When readings move faster than glucose can, VT suggests checking the sensor rather than treating the reading as real.
• Daily figures. Each morning VT records the day's mean glucose, your fasting glucose (taken at the moment your sleep ended, not when you got up) and an HbA1c estimate once there is enough data. If you log ketones, it also records your glucose–ketone index.

Which monitors.

• Sibionics GS3, the sensor VT is designed around.Live
• FreeStyle Libre 2 Plus, through LibreLinkUp. VT is not affiliated with Abbott.
• Ottai, and other Nightscout-compatible uploaders such as xDrip.

Readings are also written to Apple Health and Google Health Connect.

More about CGM with VT →

A plan built on what you actually burn, with floors it will not cross.

Set where you want to be (a weight, a range, or no target at all) and how fast: a pace in kilograms or percent of body weight a week, a daily calorie deficit, or a finish date. Set any two and the planner solves the third.

Built on your measured energy.

• The planner uses the calories you actually burn, learned from your weigh-ins and logged meals rather than a formula. The first two weeks calibrate it.
• It shows the figure VT picks, its likely range, and a plain word for how sure it is.
• Each kilogram you lose is priced at your own body composition and protein intake, not by a rule of thumb.

Pace, with its costs visible.

• Faster plans cost more muscle, so the fastest zone stays locked until you open "Show me the numbers".
• Your personal limit says why it is where it is: your calorie floor, or simply as fast as your body fat can supply energy.

Floors it will not cross.

• A protein floor: 1.6 g per kg, raised to 1.8 in the faster zone; on GLP-1 medication the planner suggests strength training to protect muscle.
• A calorie floor it never breaks: if a plan would cross it, the pace eases instead.

Make it stick.

• Breaks. Planned breaks, suggested when your data calls for one or scheduled (two weeks on and two off, three and one, or four and one).
• An optional kick-start. Some situations rule a kick-start out altogether, and the planner says why.
• A "protect muscle" setting. For when you train for strength.
• A landing. Weeks at maintenance once you reach your target.
• Medication. If you take an appetite-affecting medication such as semaglutide or tirzepatide, tell the planner whether your dose is rising, steady or coming down, and the plan accounts for it.

What you did, beside what it changed.

Activities shows your week's activity level; rings for training load (or Activity Units, if you do not log training) and steps, with your vitals at their center; and a timeline of the day: waking, sessions, protocols, and your first and last meals.

Sessions arrive on their own. While the app is open, VT checks your health store for finished workouts from your watch, ring or phone. Link a session's name once, and future ones log themselves.

Effort, measured properly. Training load is effort (the Borg CR-10 scale) multiplied by minutes. Where your watch rates effort, as Apple Watch does, VT uses that rating or waits for yours. For sources that never rate effort, VT derives it from your heart-rate reserve, and only then uses your usual rating, marked as such.

Protocols count too. Sauna, cold shower, breathwork, mindfulness, red light, morning and evening sunlight, an evening wind-down, or your own. They log on duration alone.

Every session in detail. Heart rate and zones, energy and intensity. Pace, cadence, and the route with elevation and per-kilometer splits. A note when GPS and your watch disagree about distance. With a Polar H10 chest strap, its heart rate replaces your wearable's and adds an HRV chart.

Supplements, run like a protocol and checked like one.

Build your plan in groups (morning, midday, afternoon and evening, renamed as you like), each with a usual time and an optional reminder. For each product, set the amount, with the active ingredient per unit; the days it is due; and whether it runs continuously or in cycles, such as five days on and two off.

Today. Tick each item as you take it, or adjust an amount or time. Mark a dose as skipped, or add an off-plan dose. Items not due today stay out of the way. Editing the plan never rewrites past days. Reminders arrive only on days something is due, and disappear once the group is logged.

Review your plan. With your permission, VT checks your plan in three ways:

• Dosing. Each product's daily total against usual daily ranges from the NIH Office of Dietary Supplements, EFSA and published reviews. It flags anything above the tolerable upper limit.
• Interactions. From a referenced interaction database, including with the medications you list. Worst first, with severity, the strength of the evidence and PubMed citations.
• Timing and pairing. Notes on timing, taking things apart, and taking them with food, screened for misinformation risk before you see them.

An item with no interaction research is listed as "not checked". VT never shows it as safe by leaving it out.

Adherence, honestly counted. The share of due doses you took, over 30 days to a year, with skipped doses shown separately; a day grid you can tap, and each item's schedule in words; a cycled item's off days read "Planned break", never a gap; and with fewer than seven logged days, counts only.

Morning and evening light, timed to your own sky.

Light soon after waking and the fading light of dusk are the cues your body clock sets itself by. Dawn and Sunset Alarms make them a habit you can see.

On your phone, for your sky. Sunrise and sunset are calculated for where you are, on your phone, with NOAA's solar equations, accurate to about a minute and working offline. Your location never leaves the phone.

The alarms. A silent notification at sunrise, and one 30 minutes before sunset. In the hour before, a countdown banner on Home. Then a card with the goal: for Dawn, 5–10 minutes outside within the first hour of waking, without sunglasses and not through glass, and overcast still counts; for Sunset, the last 30 minutes before the sun goes down. Up more than an hour after sunrise? The window starts when you woke ("Dawn · you woke 7:20 am").

Log it, and a ten-minute session goes into Activities, where you can edit it. If you missed it, say so, and the miss is kept honestly. Remind me later asks again in 20 minutes. A seven-day row of dots shows your streak, and it counts the sessions you log by hand too.