This app might help. It shows the package name for both user apps and system apps. Mostly I'd say the package name will indicate where it came from, but some of the names you may have to google search to find it's 'identity'.
You can check it on a per app basis by looking at the App info. Long press the app's icon and click App Info. Somewhere around the bottom under Advanced you'll see an item "Store". FakeStore is Aurora, F-Droid is... well... F-Droid.
Description: Ive started working on a tool to clean up after apps (inspired by this thread). Nobody is perfect and android neither. Apps you have already deleted sometimes leave data behind. The system constantly creates logs, crash reports...
If you go into the app details (long press the icon, press the Information symbol) and scroll to the bottom, it will tell you where the app was installed from. Of course this is only really helpful for looking at one app at a time.