Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Goodbye Tracking? Impact of iOS App Tracking Transparency and Privacy
  Labels   Tracking is a highly privacy-invasive data collection practice that has been
ubiquitous in mobile apps for many years due to its role in supporting
advertising-based revenue models. In defence of user privacy, Apple introduced
two significant changes with iOS 14: App Tracking Transparency (ATT), a
mandatory opt-in system for enabling tracking on iOS, and Privacy Nutrition
Labels, which disclose what kinds of data each app processes. This paper
studies two versions of 1,759 iOS apps from the UK App Store: one version from
before iOS 14 and one that has been updated to comply with the new rules.
  We find that Apple's new policies, as promised, prevent the collection of the
Identifier for Advertisers (IDFA), an identifier used to facilitate cross-app
user tracking. However, many apps still collect device information that can be
used to track users at a group level (cohort tracking) or identify individuals
probabilistically (fingerprinting). We find real-world evidence of apps
computing and agreeing on a fingerprinting-derived identifier through the use
of server-side code, thereby violating Apple's policies and exposing the limits
of what ATT can do against tracking on iOS. This is especially concerning
because we explicitly refused opt-in to tracking in our study, and consent is a
legal requirement for tracking under EU and UK data protection law. We find
that Apple itself engages in some forms of tracking and exempts invasive data
practices like first-party tracking and credit scoring from its new rules. We
also find that the new Privacy Nutrition Labels were sometimes inaccurate,
especially in less popular apps.
  Overall, our findings suggest that, while tracking individual users is more
difficult now, the changes reinforce existing market power of gatekeeper
companies with access to large troves of first-party data.

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The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: econ
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The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: stat