Windows 10 has a dark theme and a light theme. You can change themes from the Settings app but that’s all you can do. You will need other apps to schedule when the theme changes, and if you need a quick way to toggle it. The theme change doesn’t extend to anything else. If you’d like to change the wallpaper to match the current theme i.e., a dark wallpaper to go with the dark theme, and a light wallpaper to go with the light theme, you will need yet another app for the job. Darky does it well.
Change wallpaper with theme
Download and install Darky. Select the ‘Enable automatic theme’ option to populate the app’s options. Use it to schedule when you want to change the theme and make sure you check the ‘Change app theme’ and ‘Change system theme’ so that it will actually change the theme. You also have to enable the ‘Change wallpaper’ option.
One wallpaper is set for each theme and when the theme changes, it triggers the wallpaper change. Click the ‘Browse’ button and select a wallpaper for both the light and dark themes. When you’re done, close the app. On schedule, it will change the theme for your Windows 10 PC, and the wallpaper.
Darky works really well but you might run into a few visual bugs when the theme changes. This has less to do with the app and more to do with Windows 10 which doesn’t handle switching between its own themes very well. Your system might also freeze for a while when the theme is being changed.
Darky is pretty great overall but its scheduling feature is somewhat restrictive. The themes can only be set to change once in the AM and once in the PM. If you want to trigger both theme changes in the AM or in the PM e.g. at 12PM and 6PM, you can’t. Other than this one restriction, the app is great. It’s designed well and it’s lightweight. It’s also open-source.
Windows 10 doesn’t have plans to add a native scheduling feature to its themes. macOS started out much the same way but Catalina now lets you set the theme to change automatically based on time of day. It too doesn’t have a scheduling option but the region-based change puts it one step ahead of Windows 10. The themes on Windows 10 still need work in terms of their design since the light theme is rather awful compared to the default one that Windows 10 had before.