HACKER Q&A
📣 holidaytrucksky

How does the Twitch iOS app keep me logged in after reinstalling it?


I thought that deleting an iOS app would delete all data related to that app. How does the Twitch app still know my account after I delete it and instal it again?


  👤 solumos Accepted Answer ✓
Uber got in Big Trouble for this a while back[0]. Basically, device fingerprinting[1]. It seems like it's sort of OK now?

[0] https://the-parallax.com/2017/04/26/uber-device-fingerprinti...

[1] https://nshipster.com/device-identifiers/


👤 searchableguy
Slightly related, I was able to take over an account with functionality similar to this in one of the apps from a big tech company recently. I reported it but no response so far.

Are there companies using unique fingerprinting methods to map users for faster logins? I didn't test it further. It happened accidentally.


👤 neximo64
Apple keychain