Are you sure the app remembered it and it wasn't auto filled by Android, the system will remember usernames and passwords separately from the app data and auto fill
Android
DROID DOES
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No I'm not sure. I'm just telling it like I saw it. It was creepy.
I didn't know Android did that. I was under the impression that whatever I entered in an app stayed in the app - unless I deliberately copied it in the clipboard of course. I have never seen Android autofill anything.
But then, if I uninstalled the APK and immediately reinstalled the same APK, why didn't Android autofill my account name again after I reinstalled it?
Given you are on Calyx, I highly doubt that the system autofilled it. This is a mystery!