Circadia

Circadia is a minimalist, astronomical watch face that shows the sky in real time based on your location. The 12 o'clock position is your northern horizon, with the centre directly overhead. Face north, and the sky on your watch matches the sky above you. As the sun sets each day, its halo shifts from yellow to red, reaching purple at nautical twilight, then blue by astronomical twilight. Full night begins only once the halo has completely passed below the horizon. Stars appear through nautical twilight, reaching peak density by full night. At dawn, the transition reverses. The minute digits take on the halo's colour, while the hours flare orange through sunset and sunrise. The moon shows its current phase and position, with the illuminated side always facing the sun, just as it does in the real sky. Circadia is mathematically detailed but visually quiet. It's a "normal" watch face first, but one that reminds you to look up sometimes, and to notice the rhythms behind the hours and minutes: the path of the sun, the phases of the moon, and the turning of the stars. Currently supports AMOLED devices. MIP support and additional options planned for future release. If you enjoy using Circadia and want to support future development, you can contribute to my coffee fund: https://ko-fi.com/79north

2026.05.23 - "None" is now available as an option for each data field 2026.05.20 - Tentatively adding MIP support: FR245, Fenix 8 Solar, Enduro 3 2026.05.17 - Full-moon glow now visible on surrounding evenings if the true full-moon moment occurs during local daytime. Stars "popcorn" in (rather than fading in) after civil twilight, with a richer color palette. Moon size can now be adjusted in the menu.