A cool feature could be the use of budgets. Like setting a limit to how much you spend per day/week/month or even by category.
I’m not sure about forcing a limit on spending as I imagine a few scenarios where this could be a bit awkward, e.g. having no service in a restaurant but needing to pay the bill.
I think it would be cool to get some kind of custom notifications for this type of thing:
“You’ve spent £53 of your £60 budget on so far this month.”
I agree I would like some budgeting and Bill splitting functionality