How to switch on dark mode
Dark mode is available in Labs to everyone using version 4.44.0 of the Monzo app on iOS13+ or Android 10+.
Head to the Home tab
Tap on your profile icon (if you can’t see that, swipe down on your card)
If needed, tap on the settings cog
Tap Theme
Select the theme you'd like to use
If you're on iOS13+ you may need to fully close the Monzo app and open it again in order for the app theme to update.