SuperFontan app icon SuperFontan

Fitness for Fontan hearts.

A training and health companion for people living with Fontan circulation and single-ventricle congenital heart disease. See every metric against the benchmarks that actually fit your physiology — then train toward them.

iPhone — coming soon to the App Store Android in development On-device by default
SuperFontan Metrics tab showing a Fontan Score of 77 and a resting heart rate chart against Normal and Super Fontan benchmarks
The idea

Standard fitness apps grade you on the wrong curve.

A Fontan heart pumps blood to the lungs passively, so “normal” population targets for heart rate, VO₂ max or oxygen saturation don’t apply. SuperFontan plots every metric against two Fontan-specific benchmark bands instead, with a plain-language status under each chart.

  • Normal FontanA typical value for adults with Fontan circulation — the line to beat.
  • Super FontanThe aspirational target, inspired by the Super Fontan exercise-rehabilitation concept: what a well-trained Fontan heart can reach.
  • YouYour own data, pulled from Apple Health or Health Connect, trended over time.
  • Fontan ScoreAll of it rolled into one 0–100 number: how close you are to Super Fontan overall.
MetricNormal FontanSuper FontanBetter is
Resting heart rate60 bpm50 bpmlower
Walking heart rate100 bpm90 bpmlower
Heart rate variability (SDNN)50 ms80 mshigher
Heart rate recovery (1 min)12 bpm25 bpmhigher
VO₂ max30 mL/kg·min40 mL/kg·minhigher
Blood oxygen (SpO₂)94%97%higher
Respiratory rate16 br/min13 br/minlower
Daily steps7,00010,000higher
Weekly running distance5 km10 kmhigher

Default benchmarks as shipped in the app — general starting points, configurable, and meant to be reviewed with your congenital-cardiology team. Running speed, power, stride length and active energy are benchmarked too.

What’s inside

Everything a Fontan athlete tracks, in one place.

Metrics

Resting and walking heart rate, HRV, VO₂ max, heart-rate recovery, blood oxygen and respiratory rate — each charted against both benchmarks.

Training

Fontan-appropriate workout suggestions aimed at your weakest areas, plus a library: zone-2 cardio, gentle intervals, light strength, mobility and recovery breathing.

Activities

Running speed, power and stride length, weekly distance, steps, active energy and recent workouts.

Tests

Labs and cardiopulmonary exercise tests from Apple Health Records or entered by hand, each flagged normal, high or low with a visual range.

Conditions & meds

Medications and diagnoses synced from Health Records, or added manually — with optional medication and weekly check-in reminders.

AI Prognosis

A plain-English summary and per-metric recommendations. Runs fully on-device for free; Premium adds richer AI-written analysis.

Fontan Score

One 0–100 number that tells you how close you are to Super Fontan, and which metrics are holding it back.

Provider export

One tap builds a clean summary to share with your cardiologist or care team, on your terms.

Explorable first

A labelled sample preview lets you look around before granting any health permissions.

Screens

Built for iPhone, clear at a glance.

Sample data shown. Tap any screen to enlarge.

SuperFontan Metrics screen
MetricsFontan Score and benchmarked heart charts.
SuperFontan Activities screen
ActivitiesRunning speed, power and stride vs. both bands.
SuperFontan Tests screen
TestsLabs and ECG values against reference ranges.
SuperFontan AI Prognosis screen
AI PrognosisSummary plus recommendations by metric.
SuperFontan Onboarding screen
OnboardingConnect your health data in a few taps.
Private by design

Your heart data stays on your phone.

  How your data is handled

  • Processed on-device. Metrics, labs, meds and conditions are read with your permission and never stored on a server.
  • Never sold, never ads. No third-party advertising or tracking SDKs.
  • Only what you approve. Revoke access any time in Health or Health Connect settings.
  • One opt-in exception: Premium AI Prognosis sends a metrics summary — not your full record — to generate your write-up, then discards it.

Read the full privacy policy →

Free

$0
  • All tracking, benchmarked charts and training
  • Fontan Score and on-device prognosis
  • Provider export

Premium

$4.99 / month
  • AI-powered prognosis with in-depth, personalized recommendations
  • Supports ongoing development for the Fontan community
PlatformHealth sourceMetricsMeds / labs / conditions
  iPhoneApple HealthKit + Health Records (FHIR)Full, incl. VO₂ max, running dynamics, HR recoverySynced from Health Records
  AndroidGoogle Health ConnectEverything Health Connect exposesManual entry

Not medical advice. SuperFontan is for information and general wellness only. It is not a medical device and does not provide diagnosis or treatment. Always confirm training or medication changes with your congenital-cardiology team. In an emergency, call your local emergency number.

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