Circadian is a live wallpaper that changes on its own — one photo for the day, another for the night, switched automatically at the time you choose, or synced to real sunrise and sunset at your location.
No manual switching. No remembering to change your background. Set it once and your phone matches the time of day, every day.

★ AUTOMATIC DAY & NIGHT SWITCHING Pick a day photo and a night photo. Circadian swaps your live wallpaper on schedule — even after a reboot or when battery saver kicks in, your schedule keeps running.

★ REAL SUNRISE & SUNSET SYNC Turn on Auto mode and Circadian calculates today's actual sunrise and sunset for your location, so your wallpaper follows the real sky, not a fixed clock. It re-syncs automatically as the seasons shift.

★ LIVE MOTION EFFECTS
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Swipe parallax between home screens, with an optional smooth-follow mode for a more natural motion feel
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Zoom-in on unlock, smooth zoom-out on lock — a subtle, cinematic touch every time you pick up your phone
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Fine-tune speed and intensity with simple sliders, and sync settings between your day and night wallpaper in one tap

★ BUILD YOUR OWN WALLPAPER HISTORY Every photo you add is saved to your personal wallpaper history with instant thumbnails — browse, reapply, or delete with a long press. Your most recently used wallpapers always float to the top.
★ DISCOVER WALLPAPERS FROM THE WEB Browse a large library of free wallpapers, search by category or color, and preview similar wallpapers based on what you're already looking at — right inside the same preview screen.

★ MATERIAL YOU COLORS Circadian adapts your system colors to whatever wallpaper is currently showing, for a phone UI that always feels tied together — no setup required.

★ CROP, ZOOM & PREVIEW BEFORE YOU APPLY Pinch, drag, and crop any photo exactly the way you want before it becomes your wallpaper — full-screen preview, every time.

★ BUILT TO KEEP RUNNING Circadian survives reboots, battery optimization, and power-saving mode. If the system pauses your schedule, Circadian picks it back up automatically the moment power saving turns off.
Bonus for advanced users: an optional AI effect generator (powered by Gemini) lets you turn any photo into custom shader-based variants using your own free API key.
Set your day. Set your night. Let Circadian handle the rest.