[Double_a_92]

How do you casually link your bank account to some app? Is it common for banks to have safe readonly APIs or so in your country?

[nr152522]

Yes, take a look at the OBIE [0]. You are required to be registered/regulated as an appropriate 'Third Party Processor' (TPP) class, in this case an AISP.

Then you can use an API aggregator service such as SaltEdge, TrueLayer, Teller [1], etc. (I'm not associated with any of these). Or you can try to roll your own.

[0] - https://www.openbanking.org.uk/about-us/ [1] - https://www.truelayer.com https://www.saltedge.com https://www.teller.io