My bank provides the APK of their app directly on their website, and it supports updating itself after that. Actually a surprising amount of apps do this!
Other proprietary stuff I either get from RuStore (Russia-specific), or occasionally from APK mirrors / Aurora. At the moment I have no such apps (they're usually for some specific thing, e.g. an airline app that I need for a day or two).
My bank provides the APK of their app directly on their website, and it supports updating itself after that. Actually a surprising amount of apps do this!
Other proprietary stuff I either get from RuStore (Russia-specific), or occasionally from APK mirrors / Aurora. At the moment I have no such apps (they're usually for some specific thing, e.g. an airline app that I need for a day or two).