The increasing usage of mobile devices within the healthcare domain and the social sector requires a closer look on privacy and security aspects of those systems. Major data breaches have been made public in recent years, which resulted in privacy issues for unaware users, ranging from loss of control over their data, to identity theft cases, up to discrimination because of political, religious or sexual orientation. To this aim, privacy enhancing technologies enabling privacy-preserving communication and data sharing are investigated in the context of an mHealth solution.