Newshot Article title: Aerial Switcher: Putting macOS Aerial Wallpapers on a Schedule
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The article represents the author's personal views; SSPAI only made slight edits to the title and formatting.
macOS's built-in aerial wallpapers have a rather odd quirk: Apple shot multiple time-of-day versions of places like Tahoe, Sequoia, and the Golden Gate, and macOS 27's new Golden Gate, for example, has four videos—daytime, sunset, dusk, and night. But in System Settings, they're four separate wallpapers.
You pick sunset, and when you open your computer the next morning, it's still sunset.
I found that a bit of a shame. Since Apple has already filmed the same place from morning to night, why not let them switch automatically with the time?
And so Aerial Switcher came to be—a minimal menu bar utility that lets macOS aerial wallpapers switch by time of day.
From Morning to Night
The first time you open Aerial Switcher, a settings window appears. Once you've picked a favorite location, the app automatically checks for and downloads any missing aerial videos, then switches to the version matching the current time.
The default schedule is morning 06:00, daytime 12:00, sunset 17:00, dusk 18:00, and night 21:00. Different locations have different numbers of videos—Sequoia, for example, only has morning, daytime, and night—so these times may not suit you. That's why I built a 24-hour timeline where you can drag the handles to adjust switch times directly, in 15-minute increments.
If it gets dark early in winter, for instance, you can move sunset up to 16:30.
Once set up, you can forget about it. The app stays in the menu bar, with the icon showing the current time period. Click it to see when the next switch will happen, or to swap in another set of wallpapers. If one particular scene looks especially good, you can pause and keep it there indefinitely; if you don't want to use it anymore, turning off automatic switching restores your original wallpaper.
The app also checks the time when your Mac boots, logs in, or wakes from sleep, so it won't miss a switch.
How macOS Wallpapers Actually Work
This tool started out as a command-line program you invoked with make, and gradually became the menu bar app it is now.
While building it, I discovered that macOS doesn't provide a public API for setting aerial wallpapers directly. However, the system's wallpaper configuration is actually stored in a plist file:
~/Library/Application Support/com.apple.wallpaper/Store/Index.plist
Modify the configuration in it and restart WallpaperAgent, and the system will load a different aerial video. There's a catch here too: the aerial videos aren't necessarily already downloaded to your machine. If you switch directly to a video that doesn't exist, macOS won't download it automatically—it just shows the default wallpaper.
That's why I added automatic downloading. The app fetches missing videos from Apple's servers and stores them in macOS's original aerial directory. Each video can be several hundred MB, so the first time you pick a wallpaper group, you'll need to wait a bit.
To avoid disturbing your existing desktop settings, the app backs up the configuration before taking over the wallpaper and restores it when switching is turned off. If you change the wallpaper yourself in the meantime, your changes are preserved too.
That said, these methods rely on undocumented internal macOS mechanisms, and a future system update could break them. Compatibility has been tested on major and minor releases of macOS 26 and 27.
Download
Aerial Switcher is now on GitHub, free and open source under the MIT license. You can download it from the repository's Releases page, unzip it, and drag it into the Applications folder to install. The whole app is about 2 MB. It also isn't notarized by Apple yet, so the first launch may be blocked by macOS—go to System Settings › Privacy & Security, scroll to the bottom, and choose "Open Anyway."
This is the first time I've fully packaged and released a macOS tool I made myself. It doesn't do much, and the interface still has plenty of room for improvement, but it has finally gone from an initial command-line program to an app you can install and use directly.
If you run into problems, feel free to file an Issue on GitHub, and you're welcome to share your thoughts in the comments.
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