A Civil Twilight
First light & last light times
$1.99 · Designed for iPhone. Not verified for macOS.
Four times that matter: first light, sunrise, sunset, last light. On your wrist, for any day, anywhere — computed on-device from your location. No network needed.
A Civil Twilight shows the four solar times that define usable light:
• First light — morning civil twilight begins
• Sunrise — morning twilight ends
• Sunset — evening twilight begins
• Last light — evening civil twilight ends
Glance at your watch or phone and know exactly how much light you have
left — out hunting, on the water, flying, photographing, or just planning
a dawn run.
WHY CIVIL TWILIGHT?
Civil twilight (sun within 6° below the horizon) is the standard that many
hunting regulations, FAA night-flight logging rules, and boating
navigation-light requirements are written around. It is also the
photographer's blue hour. This app gives you those boundaries precisely,
not approximately.
ON YOUR IPHONE
• Today's four times, front and center, on a twilight-sky backdrop
• Swipe up or down to step through days; jump anywhere with the
full-screen calendar
• Twilight alerts: get notified 5, 30, 60 minutes — or any custom
lead time — before first light or sunset
• A built-in field guide: what civil twilight is, the 6° rule, the
golden hour, and why these four times matter
• Choose your look: Twilight, Light, Dark, or Auto
ON YOUR APPLE WATCH
• All four times at a glance for your exact location
• Scroll through any day, ±180 days; tap the date for a calendar
• The period you are in right now is highlighted
• Watch-face complications: next light boundary, current solar window,
and first/last light
PRIVATE BY DESIGN
All calculations happen on your device using standard solar math. Your
location never leaves your watch or phone. No account, no ads, no
tracking, no network connection required.
Works anywhere on Earth, including high latitudes (where the sun may not
cross a boundary on a given day, the app shows it honestly).
From PresenceProof by JSC Biz LLC.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, JSC BIZ, LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- JSC BIZ, LLC
- Size
- 10.6 MB
- Category
- Weather
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later. - Apple Watch
Requires watchOS 9.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 JSC Biz LLC
