The Smart Thermometer is an electronic thermometer for calves and cattle with Bluetooth connection to a smartphone and Förster-Technik's CalfCloud technology on the Internet. After recording the animal's number, the rectally measured body temperature and time of measurement are recorded and transmitted to CalfCloud, which already contains all the other calf data. In the associated "CalfApp VITAL", other important results such as nasal discharge, faeces or cough can be recorded for health assessment. The Smart Thermometer communicates with a smartphone that runs the "CalfApp VITAL" application. A selection list of animals to be measured is loaded onto it. Once an animal has been selected, the measured temperature is assigned to it and stored permanently in the CalfCloud. To do this the smartphone must be connected to the Internet. If there is no Internet connection during the measurement, the data is stored and synchronized with the CalfCloud when the Internet connection is available again.