How iOS apps store user data and how to delete it?

Question

iOS

How iOS apps store user data and how to delete it? A simple example with google maps, dropbox, etc. I am authorized in dropbox on my iOS device, after installing mailbox, the application immediately prompts me to log in with my name without using a password. An example regarding Google applications: I deleted all Google applications that were on the device, I download again, just like in the previous case - it offers to log in under my name + no passwords are required. I would like to understand where this information is stored and how it can be deleted?

Answer 1

It seems to me that iCloud and a bunch of keys are involved here.

Answer 2

Smartphones running both on iOS and Android, before downloading any applications from the App Store and Play Market, respectively, are asked to register. You create an AppleID or Gmail account, which stores all the information about what applications you downloaded, what sites you viewed, etc. This is called "total" surveillance and collection of information about each. You can delete accounts, but you will not be able to use the services.

Answer 3

You can delete it by completely resetting your smartphone, this is a 100% option. You can also try cleaning application data with Mac programs like PhoneClean, but it already depends on the application.

Answer 4

NSUserDefaults, NSKeyChain, iCloud.