coming soon to iPhone

Your day, synced
with the sky.

Sleep scores tell you what went wrong. Opsin tells you what to do about it — one clear action a day, matched to your sun, proven in your own sleep and recovery.

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06:13civil dawn 06:41sunrise 20:50sunset

the root, not the symptom

Nearly every way we feel unwell traces back to a clock out of sync.

Every cell in your body runs on a roughly 24-hour clock, and a master clock in your brain keeps them aligned. The signal it depends on most is light — the right light, at the right time of day.

A regulated circadian rhythm is foundational to health — as fundamental as what you eat or how you move. When its timing drifts — from dim mornings, bright nights, screens, shift work, travel — every clock in the body falls out of step. And a growing body of research points to circadian dysfunction as a major, arguably driving, factor in the development of chronic disease: poor sleep, low energy, mood disturbance, metabolic dysfunction, blood-sugar and cardiovascular strain, blunted focus, weakened immunity and recovery.

Treat each of those as its own separate problem and you end up managing symptoms forever. Address the timing underneath them, and you're working on the cause.

Most tools hand you more data about the problem. Opsin gives you a behavioral solution — and fewer numbers to carry.

Opsin is a general wellness app, not a medical device, and does not diagnose, treat, or cure any condition.

why Opsin is different

A sleep score tells you that you slept badly. It never tells you what to change.

Most apps

  • Show you charts, scores, and trends
  • Measure the problem in ever-finer detail
  • Leave you to figure out what to do with it
  • Add another number to track every day
  • Feed anxious over-tracking — nervous-system dysregulation dressed up as insight
  • Confuse more data with more progress

Opsin

  • Computes your real local sun times
  • Works on the cause — your light timing
  • Turns your sky into a clear next step
  • Adapts to your rhythm as it shifts
  • One calm action, then you're done — no doom-scrolling your own data
  • Proves it worked in your own body

Light sets your clock. Opsin sets your light.

what's inside

Less to track. More that changes.

Your day, computed for you

Civil dawn, sunrise, golden hour, and sunset — calculated on your device for your exact location, with a living sky that moves as the sun does.

One next action

Not a wall of metrics — the single most useful thing to do for your rhythm right now, and how to do it.

Morning-light streak

Build the habit that anchors everything. Log your time outside, back-date a day you missed, and watch the streak grow.

Proof from your own body

Connect Apple Health and see how your sleep and recovery compare on days you got morning light versus days you didn't.

Wake with the dawn

An alarm that tracks the sunrise and re-times itself as the seasons change — so you wake into the light, not against it.

Jet-lag coach

Enter a trip and get a day-by-day plan with the exact clock times to sleep, wake, and seek or avoid light. No math required.

Your lights, on sun time

Connect Apple HomeKit and Opsin warms your lights at dusk and brightens them at dawn — automatically.

Night-screen guide

A simple setup that reddens your phone after sunset to protect your evening melatonin and wind-down.

Know your chronotype

A quick assessment places you as a morning, evening, or intermediate type — and tailors your guidance to it.

A daily verse

An optional word of light, rest, and hope each morning — 365 verses, chosen to meet the day.

Private by design

Your data stays on your device. No account required. Nothing sold, ever.

Widgets & Siri

Your next light window at a glance on the home screen, and hands-free logging through Siri.

why I built it

Across years in cardiology and functional medicine, the same root kept surfacing: a rhythm out of sync with the sun sits underneath so much of how we feel. Every tool I found just handed people more data about the problem. None of them fixed the cause. So I built the one I wanted them to have.
Built by a nurse practitioner · cardiology & functional medicine

coming soon to iPhone

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Join the waitlist and we'll let you know the moment Opsin is on the App Store.

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