No matter whether payment of the public passenger transport ticket is made via a smartphone app or whether a prepaid card is used for the public swimming pool or a bonus card for the supermarket: Many people already open their “electronic purses” every day. However, most of them are not aware of the fact that by doing so, they largely lose privacy. Researchers of Karlsruhe Institute of Technology (KIT) have developed a secure and anonymous system for daily use. It will be presented at the ACM CCS 2017 conference in the USA.