How Vitality Tracker works.

What you need

A phone, and one thing that measures you. A body-composition scale, an entry-level band, a watch, a ring or a glucose sensor each gives VT a place to start, and a thirty-dollar scale with a basic band is a complete setup, not a compromise. Nothing yet? Every measure can be entered by hand. Add a device whenever you like and VT starts using it the same day.

VT opens on the screen that suits what you own: a wearable opens Today, with sleep, recovery, heart and activity; a scale opens Body Composition; a glucose sensor opens the live Glucose dashboard. Fasting, meals, supplements and shopping lists work on every path.

Start from a baseline

None of this needs a blood test or a glucose sensor. But if you are serious about your health, two things in your first month make everything afterwards sharper: a baseline lab panel, taken before you change anything, which gives VT the markers its indices are built from and fixes the point every later result is measured from (recommended baseline panel →); and a month on a continuous glucose monitor, which shows how your body handles your own meals, fasts and nights rather than how an average body does. If a baseline result sits outside the laboratory’s reference range, VT suggests a consultation: take your pre-visit report to your own GP, or book a private video consultation with a doctor who works with Vitality Tracker, at the member rate on paid plans and for everyone during the beta.

Measure: connect once, and VT works out the rest

Anything that writes to Apple Health or Google Health Connect reaches VT, from any brand. Where a maker allows it, VT connects directly instead, because a direct connection carries more than the health store does: Oura, Fitbit, Polar and Withings each take one sign-in; the VT Longevity Pro Scale and a Polar H10 chest strap pair over Bluetooth from inside the app; a Sibionics GS3 CGM through our official integration; a FreeStyle Libre 2+ signs in once with LibreLinkUp, and an Ottai sensor connects through Nightscout.

Then VT does three things most apps do not. It pulls the health store's mix apart, so your sleep comes from your ring, not from a blend of ring and watch. It lets each part of the app use the device that measures it best: a ring for sleep and a watch for the day, if that is what you own, chosen by you or left on Automatic. And it names every device with what it can give, such as "Full" or "No daytime HRV", so you choose knowing what you will get. Setup ends with a plain list of what is there, what is missing and how to fill the gaps.

Understand: your own normal is the reference range

A resting heart rate of 62 is ordinary for one person and high for another, so VT first learns your usual range for each measure, over a rolling window of about 30 days, and reads every new night against it. Early results are marked provisional and firm up as your history grows. Two engines then ask the two questions no single number can answer.

• Level. Each morning, Symptom Radar compares last night with your normal across five independent signs, your heart, your sleep, your breathing rate, your temperature and your blood oxygen, and tells you whether your body looks settled or under strain. Hard training, alcohol, a late meal and your period all move those readings, so when you log them, VT weighs the affected readings less.
• Velocity. Symptom Trend asks how fast things are moving: a jump from one night to the next, or a drift over several days that no single night would show.

Alongside them: an energy engine that works out how many calories you really burn from your weight and what you eat, rather than trusting a watch; two sleep scores, one for last night and one for the last four weeks, with regularity carrying the most weight and sleep stages drawn but never scored; a Vitality Score that sums five areas of metabolic health into one number you can open; and, from a blood-pressure cuff, two figures that describe your arteries. Eir, VT's AI health coach, reads all of it and explains it in plain language, with the evidence behind each statement, and it describes rather than diagnoses.

Act, then share

What VT finds becomes something to do: a Playbook that turns your goal into targets and floors, a weekly meal plan that feeds the energy engine, supplements run as regimens, a fasting timer, training and protocols logged beside the measures they move. And when you want a second opinion, your doctor or coach gets time-limited, read-only access and a pre-visit report of what has changed and since when, so the appointment starts from your data rather than your memory, and it costs them nothing.

What you will see, and when

Every engine learns from you, so each needs some history before it says anything. With a device syncing every night from day one:

A missed night is skipped, never counted as a bad one; it only moves the later dates back.

Five things VT will not do

1. Blend devices. An Oura night and an Apple Watch night are never averaged into one figure, and a change of device is marked, never hidden.
2. Fill a gap with a guess. A missing reading shows as a dash with the reason.
3. Score what it cannot measure. Consumer devices cannot grade deep and REM sleep reliably, so VT shows your stages and leaves them out of the score.
4. Pretend four readings are ninety-six. Every overnight figure carries its count of readings and its method.
5. Diagnose. VT describes and tracks your measures against your own history, for general wellness and for discussion with a health professional. If you feel unwell, see one, whatever your results say.