Here is a compact wireless temperature & humidity sensor that records data and sends alerts directly to your smartphone. The tempi.fi Mini Bluetooth thermometer and hygrometer is ideal for monitoring conditions in your refrigerator, greenhouse, or baby’s room. You get to analyze years of historical data on your phone and export it in CSV format.
Users have the option to set high or low temperature and humidity alerts. The device runs on a coin cell battery up to a year.[where to get it]