If you have an iPhone or iPad, you can turn on system-wide dark mode rather than activating it app by app. Your iPhone must be running iOS 13 or higher, and your iPad must have iPadOS.
Putting both Today and Upcoming in Slide Over is another great option, because you can easily switch between them now that Slide Over supports multiple apps and the iPhone ... that’s the mode that ...
If you have an iPhone or iPad, you can turn on system-wide dark mode rather than activating it app by app. If you want to set specific times for dark mode and light mode, tap the Options field ...