The ability to switch between light/dark mode and design them in Adalo. The native app switches to dark mode when the phone switches to dark mode. The Logged in user can choose between the modes.
Or the ability to select a secondary Branding Theme - this way you can control the colours 
I’d also like to add that the initial loading screen for any app is a white screen with a blue loading circle. This cannot be changed by the a;;'s branding. In dark mode, we should be able to darken this too.
This is a much needed feature - integration with the appropriate system level features on both iOS and Android. Apple is soon requiring all new apps to support dark mode automatically. Hopefully it is made available soon!
Yes, a lot users use this nowadays (Me first, all my phone is in Dark mode all time)