If you only knew the power of the Dark Side...
The iOS version of Collect supports Dark Mode that was introduced in iOS and iPadOS version 13. In your settings, you can go to Display & Brightness -> Appearance and turn on/off the light switch.
This will automatically activate the Dark Mode setting if the feature is supported by the app you are using. In the image below you can see the switch made in Collect.
Let us know what you think!