Theres arguments for both sides of the coin, for example someone mentioned their clients want to do most the work themselves on site, I however find most of my clients don’t, and that is why they pay me.
My clients are not interested in tagging bank transactions. At the very most they want to be able to generate an invoice, get it paid, perhaps even just upload receipts, all of which is possible now anyway.
Plus I’m certain that you could use urls to point to the right areas of the account, and just get your clients to use those. In fact it’s not hard to build your own app and include these urls as buttons.
I agree though that the cost to create a proper app will only increase subscription fees, and I can imagine there would be a flurry of people complaining they don’t need it as well.