SunSpan
Sunrise, sunset & twilight
About
Visualize an entire year of daylight, sunrise, sunset, and twilight on a single, intuitive chart. Easily inspect daily solar times and phases by tapping or dragging across the visual representation. Offers detailed insights into seasonal changes and astronomical events.
What's New in SunSpan
1.0.5
May 5, 2026
- Moon phase next to each day's sunrise/sunset details, drawn for the date you select. - Phase orientation flips for southern-hemisphere locations so it matches what you actually see in the sky.
MoreFAQ
What is SunSpan?
SunSpan renders an entire year of sunrise, sunset, and twilight as a single chart. Each day is a vertical band shaded from astronomical night through nautical and civil twilight into full daylight, making seasonal curves and solstices visible at a glance.
How does SunSpan display daylight information?
SunSpan uses an eight-stop twilight gradient, ranging from night to day, to visually represent different phases. The chart allows users to tap or drag across any day to see its specific sunrise, sunset, daylight length, and twilight phase times.
Can I see historical and future daylight data with SunSpan?
Yes, SunSpan provides a full-year daylight chart for any location and any year from 1900 to 2100, allowing for both historical and future data inspection.
Does SunSpan use my location?
SunSpan uses your location only on-device to compute solar geometry. This location data never leaves your device, ensuring your privacy. You can also pick locations manually via a satellite map.
What devices does SunSpan support?
SunSpan is available for iPhone and iPad devices.
Is SunSpan free to use?
Yes, SunSpan is available for free and does not contain any advertisements or in-app purchases.
How often is SunSpan updated?
The latest version, 1.0.5, was released on May 5, 2026, indicating regular updates to improve functionality and reliability.
What languages does SunSpan support?
SunSpan is localized in English, Spanish, German, and Ukrainian, making it accessible to a wider range of users.