Sun arc
A single curve places sunrise, solar noon, and sunset on today’s daylight, instead of a generic clock.
Sunlight and circadian rhythm
SolSync — Sunlight & Circadian Rhythm App
SolSync is an app for your own light hygiene. It shows local sunrise, solar noon, and sunset, draws a sun arc and a phase timeline, and — with Premium — times daily morning and evening light windows. It is not a coaching service and not a medical device.
Local sunrise, solar noon, and sunset
SolSync calculates sunrise, solar noon, and sunset for your location, on your device. Those three times anchor the rest of the day. If you skip location, the app can preview with a demo place instead of guessing a schedule for you.
The same screen shows where you are in the day: a sun arc from sunrise to sunset, and a phase timeline across that arc. This part of the app is there without a subscription.
A sun arc and a phase timeline
Phase timeline
The timeline marks the phase of the day you are in, from the early arc through evening.
Your location
Times follow the coordinates you allow. They are calculated locally, not copied from another city.
Morning and evening light windows
SolSync Premium builds timed windows from those local sun times: a morning window after sunrise, and an evening window around sunset. The windows move when the sun does, including across the year. Reminders fire for the windows you turn on. They are reminders only — the app does not tell you that light will treat, cure, or prevent anything.
Get the SolSync app
Open it in the browser, or install it from the App Store or Google Play.