Can I set Dark Mode dynamically on my iPhone like I can in macOS?
Assuming you have iOS 13 installed, follow these steps:


Go to Settings
Tap on Display &amp; Brightness
Enable the Automatic option (it’s just below the Light and Dark images at top)
This will reveal the Options setting - tap on this
You can now choose between Sunset to Sunrise or setting a Custom Schedule
Selecting the:


Sunset to Sunrise setting will mimic what macOS does with its Dynamic Desktop (i.e. change from Light to Dark mode based on your location)
Custom Schedule setting means you can manually select the exact times you want it to change from Light to Dark and back again



NOTE:

Since you're also wanting your iPhone background image (or Wallpaper) to change dynamically, you will need to go to Settings > Wallpaper and toggle the Dark Appearance Dims Wallpaper option. This doesn't work in the same was as it does in macOS, but your Wallpaper's appearance will change somewhat whenever your iPhone changes from Light to Dark and back again