Panther5362 I think OP means to "Mutual Consent".
The original poster indicated that either the GrapheneOS documentation or the AOSP documentation (unclear which) says "apps can't see any information anymore". Clearly that isn't accurate, so I asked for a specific statement.
Panther5362 For example my "M&S" Banking App just gave me this message:
"we've introduced additional checks to protect your account. The following apps have been downloaded from unofficial app stores. Your access to the M&S Banking app has been suspended on this device until you've taken access to restore it. Identified apps: Bitwarden"
It then tells me I need to remove it.
Surely it shouldn't be able to see any other apps or where I downloaded it from!
There are various legitimate reasons why it would be useful for one app to be able to tell whether some other app is installed, or even potentially to list all installed apps. For example, lots of apps published in Google's Play Store verify that Google Play is installed when they launch. Some of them do this because they actually won't work without Google Play being installed, and would prefer to provide the user with a useful failure message instead of just a cryptic crash dump.
In this case the bank app is trying to protect the bank's users (and also the bank itself) against behaviors that malware might plausibly use. Somebody might actually create a fake version of Bitwarden which would send passwords to a third party. The author of the bank app might believe that the version of Bitwarden available in the Play Store is probably not malware, and might be concerned that programs called Bitwarden downloaded from other places might not be legitimate.
A user with the Aurora app probably has a legitimate version of it... and thus a user with Bitwarden from Aurora probably has a legitimate version of Bitwarden... but how many users check? The author of an app published on the Play Store might believe it's a lot safer to require a version of Bitwarden that also comes from the Play Store, and the AOSP authors apparently thought it would be good to make such checks possible.