- no login bullshit (no pinsentry, or being timed out after 5 minutes or whatever)
- instant card freeze/unfreeze from the app. I don't have to talk to anyone to do it
- push notifications for every purchase (including full text entries for where the transaction was, and a cute little topical emoji)
- no hassling with PDFs of my transaction history, there's a god-damned API (and for the average consumer, there's the potential to have a constellation of 3rd party apps to deal with anything on the API). There's also in-app transaction breakdowns (for instance, I can see how much I spend in a particular category, or at a particular place). SHOW ME ANOTHER BANK WITH AN API
- I always know how much money I have in the account; there's not "available balance/actual balance" bullshit.
Honestly the main thing is that's really easy to use. I'm generally terrible at keeping track of how much money I have (usually because I avoid cash machines (I don't know who's still using cash in London, pretty much everything is contactless) and logging into online banking is a hassle). With Mondo, I can find my balance in one tap.
And yeah, they've earned my loyalty and I invested in them yesterday. Sign up for a card, use it, then criticise it.