The rad-safe app is an electronic booking and access system for safe bicycle parking systems. The bicycle parking systems serve both long-term tenants (e.g. week, month, year) and spontaneous users (e.g. daily use). Using a PIN code, the system reliably opens every bicycle parking system that is controlled via an electronic door opener. Alternatively, depending on the location, an RFID card can be used as an access medium. The user can book the parking space in advance using the rad-safe app.