Lat 35°41′22″N
139°41′30″E Lon
Folio I / IV
Plate 01 Vitality
Est. 2026 · Tokyo · An instrument for the midlife man
Sextant Vitality · Edition I

Measure
where you are.

A quiet longevity instrument for midlife men. Your HealthKit data, your blood panels, your interventions — distilled into a single bearing called Vitality, calibrated against your age cohort. Read on-device. Logged in serif.

N S W E 30° 30° ★ Vitality Observer
Sub-scores
VI composite
Lab panels
XXV w/ conversion
Intervention types
VIII incl. custom
Servers
on-device
No. 02 / ii · The Bearing

One number.
Read against your cohort.

The Vitality Score is a 0–100 composite weighted for midlife men: VO₂max thirty per cent, sleep twenty, recovery fifteen, activity fifteen, cardiovascular ten, mobility ten. Each sub-score is normalised against age- and sex-adjusted reference ranges drawn from Cooper Institute and ACSM percentile tables.

Missing data renormalises the remaining weights. Partial HealthKit permission still produces a usable bearing — the instrument adapts to the data it has.

Cardiorespiratory fitness is one of the strongest predictors of all-cause mortality. — Mandsager et al., JAMA Network Open 2018
No. 03 / iii · The Method

Four readings.
One bearing.

01

Read on-device

VO₂max, HRV, resting heart rate, walking speed, sleep stages and workouts — pulled directly from Apple HealthKit with explicit, granular permission. No accounts. No transit. The phone reads itself.

02

Score against cohort

Six sub-scores normalised against your age and sex band — Cardiorespiratory, Sleep, Recovery, Cardiovascular, Activity, Mobility. Weighted for midlife men, robust to missing data.

03

Log interventions

Sauna, cold plunge, fasting, alcohol-free runs, new supplements, new training blocks. Marked on the Trends chart so you can see whether your bearing moved with the intervention or independently of it.

04

Track blood work

Twenty-five panels — Total T, ApoB, hs-CRP, HbA1c, Lp(a), thyroid, vitamins. Automatic ng/dL ↔ nmol/L conversion. Reference and optimal ranges. A six-month follow-up nudge when it's time.

No. 04 / iv · Aboard

What's included.

Three tiers, plainly drawn. Free is enough to use the app daily, forever. Premium opens the full breakdown. Lifetime is for those who prefer to settle a tool once.

Manifest
Free
Premium / Lifetime
Today's Vitality ScoreThe single bearing for the day.
Today metrics rowSleep, HRV, RHR, steps, workouts.
Six sub-scoresCardio, Sleep, Recovery, CV, Activity, Mobility.
1 of 6
Trend history30 days · 90 days · 1 year · all.
30D
All
Age-cohort comparisonThe reference band on Trends.
Intervention markersOverlaid on the Vitality chart.
Lab panels25 midlife-male tests with unit conversion.
3
Monthly PDF reportOnyx-and-brass — share with your physician.
Data exportJSON · CSV. Yours, always.
No. 05 / v · The Tiers

Quiet pricing for quiet tools.

Pay nothing, ever. Pay yearly for the full breakdown. Or settle it once.

Free
$0
No subscription · forever
  • Today's Vitality Score
  • HealthKit metrics row
  • Interventions log (unlimited)
  • Three lab panels
  • Past 30 days of trends
  • JSON / CSV export
Premium
$8.99 / mo
or $79.99 / year — save 25% (yearly includes 7-day free trial)
  • Everything in Free
  • All six sub-scores
  • Full history (90D · 1Y · All)
  • Age-cohort comparison band
  • Intervention markers on Trends
  • Unlimited lab panels
  • Monthly PDF reports
  • Cancel anytime in Settings.
Lifetime
$179.99
One-time payment · launch year only
  • Everything in Premium
  • Forever, no renewals
  • Future v1.x feature unlocks at no extra cost
  • Available 2026 only.
On-device by default. HealthKit data never leaves your phone. Lab values, interventions and your profile live in local SwiftData. The only outbound connection in v1.0 is Apple StoreKit for purchases — and the contact form, when you tap Send.
— Cast off —

Find your bearings.

Free to download. No account. No transit.

Coming to the App Store
iOS 26 iPhone · HealthKit-native