So why can I access my bank account just fine via the website on my phone, but shouldn't be able to do the same via the app? Can't they offer at least a PWA version of the website for custom ROM users?
What guarantees your banking app is the right one? A PNG and an app name with no security whatsoever.
Typosquatting would like to have a word with you.
How did the world come to this when the internet long predated smartphones and so many "apps" are little more than bookmarked wrappers around websites?