F-Droid is a software store for open source applications for Android and is considered the most important distribution channel for free open source software for Android. This work attempts to tackle two problems of the F-Droid app store in terms of visualizing privacy-related information of the apps in a human-centered design fashion. The first problem is that F-Droid ’s privacy metadata is limited to Anti-Features, which lack depth and use technical terms that are of no use to the majority of users. The second problem is to present the privacy parameters of these apps in an informative and interactive way, moving away from the current less user-friendly text formats.
To this end, Exodus Privacy, an extensive community-driven open database of privacy-related data (e.g., trackers) of Android apps, was used to complement F-Droid ’s data. Building on existing research in the privacy visualization field (e.g., “DCI ”, CLEVER°Franke’s Privacy Label, or Stöver et al.’s research on privacy indicators), several privacy visualization prototypes were developed. Subsequently, the prototypes were discussed in expert interviews, and the preferred prototype was then refined and implemented in Neo Store, a modern F-Droid client. The study was wrapped up with a community survey to evaluate the developed design and identify potential future work.