After they announced they were removing the ability to top up via debit card I was concerned as much of their utility at the time came from being able to share costs with friends from an isolated account with a lower balance. The app has lower friction for most actions however, so I now use Monzo as a distribution account to send funds to my other bank accounts.

I still don’t use the card itself at all however as they have no cash back, and fwiw the app has started slowing down in recent months. The frame rate consistently drops noticeably below 60fps when scrolling through my transactions, for example.