Android 版的 Facebook 把整個 system library 的 metadata 都傳上去了:
Facebook scans system libraries from their Android app user’s phone in the background and uploads them to their server
This is called "Global Library Collector" at Facebook, known as "GLC" in app’s code
It periodically uploads metadata of system libraries to the server pic.twitter.com/olwk1BPMoQ
— Jane Manchun Wong (@wongmjane) August 30, 2019
而在 iOS 上,目前沒有觀察到類似的行為:
really interesting catch Jane. I have not seen this in the iOS version. my bet is that they want better stability on Android so want to analyze system library variants - and apparently did not even think to ask user permission.
— Will Strafach (@chronic) August 30, 2019
這些資訊足以識別裝置的單一性,而且難以更改,對於廣告有超大的幫助...