

Ask HN: iPhone apps: same user id across apps? - lwall_mba

I am not an app developer and tried to find an answer for this online without much success.<p>When storing information about users, would two autonomous apps identify the user by the same id in each respective database?<p>I install app_1 in my iPhone, how is my user id created in app_1&#x27;s user db?<p>Then I install app_2, would the iPhone use the same user id?<p>Or does the user id completely depends on how it was programmed on each app?<p>What if those apps use social networks to allow me to sign-in? and I use facebook in both?
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MBCook
Apple provides an ID that can be used to track users so you can tell the same
user is still using your service.

This quickly got abused for tracking so a few years ago Apple changed the way
it worked. Now the ID is specific to that install of the application.
Different apps get different IDs and if you delete an app and redownload it
that app will see a different ID.

I don't know if games can find out your GameCenter ID.

If you sign into Facebook, you've now told that app who you are. They could
compare notes with other apps to see if the same Facebook IDs have been used
and tie you together that way.

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lwall_mba
Thanks! This helps a lot. So, based on the second part of your answer,
comparing facebook ids, and other social networks, emails, etc. is what brings
Oracle and other Data-as-a-service providers to talk about identification.
Sort of trying to connect the dots across platforms, joe.black in fb, jblack
in instagram, @jb1974 in twitter, etc.

