This app requires the Windows application SPSLogger as a server. SPSLogger can be downloaded for free from our website spslog.ch. The application SPSLogger (server) is used to connect to the PLC and define the variables that are to be monitored. With the app SPSLogger (client), the state of the sensor or actuator can be controlled directly at the facility or machine. Simatic, Simatic S5, Simatic S7, S7-200, S7-300, S7-400 are registered Trademarks of Siemens Aktiengesellschaft, Berlin und M