Wireless APP Control: Bluetooth 5.0 Thermometer Hygrometer uploads data to APP when connected via Bluetooth. You can check the max and min values of temperature and humidity on APP from your phone. You can set the temperature and humidity monitoring range, and the value on the app will turn red when out of range. The alert notification will also be sent to your phone. Sensitive and Accurate: Indoor Thermometer with accurate and sensitive temperature and humidity sensor. Temperature error can be 0.5 (1), humidity error can be 5%. It refreshes once per second to provide more accurate and faster data. Export Data Storage: Indoor thermometer digital hygrometer will save data every 10 minutes to the APP, which represents a total of 100 days. Portable Design: Indoor Thermometer Smaller than others (35x 35 x 16mm). Space-saving and portable. A hanging hole is designed for various locations as you like. It can be used for about 200 days with one CR2477 battery. Wide Applications: Bluetooth digital hygrometer can be widely applied in monitoring home, office, kitchen, living room, humidor , guitar case, bedroom, wine cellars, greenhouses as well as musical instruments. It can monitor temperature and humidity changes in real time.