What are the identifiers that Android apps have access to and use to fingerprint/track users?

Questions
1

Hi,

I’m testing various “earning apps” (for curiosity/educational purposes) and have noticed they can still recognize me as a returning user, even though I create a fresh work profile with Shelter on Android 11 or 15 and delete it after each test. I also route my traffic through a residential proxy to change my IP address—since these apps can detect VPNs—and yet they still fingerprint or track me across sessions.

Thanks for reaching until the end.

2

You can install TrustDevice. It will tell you which identifiers and data are available for all apps without any permissions. It’s limited compared to the paid service though. Available on IzzyOnDroid and Google Play.

For reference some topics from GrapheneOS:

3

There is also FingerprintJS.