I used Tinder many months ago in another country and had deleted the app.<p>When I reinstalled it in an entirely different country, I was shocked to see it open straight into my previous user account.<p>I was on a different phone and wifi network, had cleared my Safari cache, and I don't use Facebook or anything that could be leaking a shared login.<p>How did Tinder know it was me? Where does it store data that persists after deleting the app? What do they use to identify the device?
On iOS, apps can store values in the device's keychain and I am not sure whether those are deleted when an app is deleted or whether disabling "iCloud Keychain" changes anything.