There are.
https://wiki.ubuntuusers.de/Finanzverwaltung/
Sorry, I didn't find a good link about Linux accounting software in English. And I'm not aware of any Apps.
I've used GnuCash before but that isn't a fun way to do accounting. It's made for proper bookkeeping.
The Standard is called HBCI and needs to be supported by your bank. (it is relatively old, though)
Banking seems to vary a lot between countries. So I'm not sure what standards (and if...) they have where you live.
There are eCommerce solutions with payment and accounting. I'm not sure if the addons that connect to your provider/bank are open.
It all boils down to an open standard being available. It feels like there is some (international) regulation missing. At least for consumers. I bet large companies have their banking accounts tied into their (proprietary) software.