Android Question How do Android apps detect multi-account?

[papysz21]

example: I am using an Android emulator, let's say LDPlayer, and even after creating a NEW instance, with a different version of Android and on a different IP of the computer, the application still somehow detects that I have used it before
How?

 

[drgottjr]

they use accountmanager. the data are cached. also PreferenceManager

from the horse's mouth: Using Account Manager lets you remember your user, no matter how many devices the user may own, ...