Nowadays, mobile devices collect a lot of private information. Therefore every vendor of a mobile platform has to provide a sufficient mechanism to secure this data. Android pursues a strategy to pass full control (and thus full responsibility) over any private data to the user. However, the Android Permission System is not sufficient for that purpose. Various third party approaches try to enhance the Android privacy policy model. Nevertheless, these approaches have to solve the problem of how to deal with Legacy Apps, i.e., apps that do not collaborate with an enhanced privacy policy model.

In this paper, we analyze various alternative privacy systems and discuss different approaches of how to deal with Legacy Apps. Based on our findings, we introduce the so-called PMP Gatekeeper, a best of breed approach dealing with Legacy Apps for the Privacy Management Platform (PMP). The PMP Gatekeeper classifies apps and deals with each class appropriately. So the user can adjust privacy settings for every kind of app. With our prototype we show, that the PMP in combination with the PMP Gatekeeper becomes a holistic privacy system. Although our prototype is for Android, our realization approach can be applied to other application platforms in order to offer a satisfying privacy system.