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Comment by micromacrofoot

1 day ago

fingerprints pick up on all sorts of things that make you different enough combined with another signal, 33 bits can be enough to single you out from anyone else on the planet... iOS can be 10-15, and given a residential IP that's plenty - always mobile is more anonymous on the web but guess what's much worse? apps.

a native app with 0 permission prompts gets you more bits than web

2 comments

micromacrofoot

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oofbey  1 day ago

No. Almost everybody using an iPhone is on the latest release, plus or minus one while updates are rolling out. For a given iOS release and hardware type almost all of those probes are highly correlated. No way there’s 30 bits of entropy in that. I doubt there’s even 10.

Now on a desktop PC sure I believe these fingerprints are highly descriptive. And in android land they probably work okay because of the diversity of products and configurations. But iPhones resist fingerprinting just because they all give the same answers.

  • micromacrofoot  11 hours ago

    I just said iOS can be 10-15, correlated with anything else it can easily be 30. Download an app and visit their support site and that's likely enough to narrow you down.

    The web provides:

    time zone language and locale (accept-language header too) iOS version screen size and pixel ratio text size dark/light mode reduced motion ad blocker extensions for safari

    An app provides (without additional permissions):

    IDFA advertising ID (unique and cross app) IDFV (vendor ID) AdAttributionKit (which apple does obscure somewhat) Battery level, charging state, volume, headphones Various appearance settings again (font, dark/light, reduced motion)

    Just slightly more permission granted via prompt can get you:

    System boot time and uptime Disk space Keyboard languages and extensions File timestamps

    Then additional individual permissions (which people agree to all the time for specific use cases)... at this level they can single you out easily: location contacts bluetooth motion sensors

    To Apple's credit they're trying to make fingerprinting more difficult and attempt to ban it entirely, but it's not at all impossible.