I use my monzo card, along with using Google Pay, so that I can use a single card for both my personal spending and joint account spending for myself and my wife. In both cases, categories like entertainment and groceries are useful but it’d be useful to also be able to tag spending as personal and joint as well as see the normal spending break-down for each of those tags.
Although it’s lower on my requests lists, it’d also be nice to link those tags to a card (through google pay or multiple top-up cards directly) so I can see my top up vs spending for each group.