Can smartphone users turn off tracking service settings?

Tracking services play a fundamental role in the smartphone ecosystem. While their primary purpose is to provide a smartphone user with the ability to regulate the extent of sharing private information with external parties, these services can also be misused by advertisers in order to boost revenues. In this paper, we investigate tracking services on the Android and iOS smartphone platforms. We present a simple and effective way to monitor traffic generated by tracking services to and from the smartphone and external servers. To evaluate our work, we dynamically execute a set of Android and iOS applications, collected from their respective official markets. Our empirical results indicate that even if the user disables or limits tracking services on the smartphone, applications can by-pass those settings and, consequently, leak private information to external parties. On the other hand, when testing the location 'on' setting, we notice that generally location is not tracked.