Dear Bunq, this discussion (and some others) got me thinking and the joint electric pulses of my brain cells came up with an idea:
Since you allow third party development with your API and with the Connect option, you hope to stimulate development of solutions which you deem not to be core. As the population grows there will be more and more solutions which all will have the same trust issue: how do users know what is actually done with their data?
So each of those parties will have to ensure there is a trusted assurance. For companies that will not be the biggest of issues but for enthusiasts and hobbyists there are bigger challenges to tackle.
For starters; why don't you offer the option to have Bunq released apps which are code reviewed by your team and then released by Bunq labeled as third party developed with limited support? I know it's not easy but then again, starting a bank isn't either.....