How does Instagram for iOS remember the login and how to delete all its data so that it asks for the login again?

Question

iOS

Actually the subject ... First of all, to understand the tracking technologies, at this stage, I want to understand how to delete all saved Instagram data from my iOS device. Please don't suggest me to logoff in the epp itself - that's not the question.

I've been evaluating this as an elementary topic, but I've been tinkering for hours with no results. So far I've tried:

• Deleted Instagram, Facebook, (Facebook) Messenger from phone
  
• Deleted all cookies in iOS Safari that I could identify as related to Instagram, Facebook or their CDN.
  
• Removed from iCloud Keychain similarly everything that looked suspicious and incomprehensible or directly referred to FB / Instagram
  
• Turned off iCloud Keychain, changed iCloud login
  
• Disable personalized Apple ads in settings
  
• Rebooted the phone
  

Even after all these manipulations, after a new installation of Instgram from the App Store, he appears with both of my accounts as if nothing had happened and says "hello, Boss!".

Tell me how he does it :) Is it really trite by Device ID, but how in this case if I sell the phone?

Answer 1

If necessary, the application developer can set access attributes for entries in the Keychain, with which these entries will be stored locally and will not fall into the iCloud Keychain. You can find these attributes in the documentation : they have a suffix ThisDeviceOnly. Here is what the description for each one says:

Items with this attribute do not migrate to a new device. Thus, after restoring from a backup of a different device, these items will not be present.

On iOS, only the application that created them has access to Keychain secrets. Neither other applications nor the user himself can access other people's records. As a result, there is only one way to delete recordings without the participation of the application that created them - to erase all data from the device.
PS It is worth adding that deleting the Keychain entry application itself does not hurt - they will be stored further.

Answer 2

A very interesting question, and it would seem that you need to turn off the Keychain Access setting
Настройки - ICloud - Связка ключей
. But this does not help, even if you clear the passwords of Instagram, Facebook and WhatsApp ...
---
But there is a switch in Instagram itself:

Настройки -Безопасность - Сохраненные данные для входа

Where in the note it is as if hinted that the binding goes to the Icloud account
. after selling the device, you need to exit iCloud (surprisingly, right?)
And to be sure, turn off the above-mentioned setting on Instagram itself.

Answer 3

if you want axis and data control, buy androids that can be rooted