The Kestrel DROP D1 and D2 can be used to monitor environmental conditions in a variety of settings where humans are active. The Kestrel Livestock Heat Stress Monitor can be hung anywhere the animals congregate. All monitors are designed to measure and record environmental conditions, including ambient temperature, relative humidity, dew point temperature, heat stress index, and temperature-humidity index. The collected data are transferred to one's iOS or Android device via the Kestrel Link app. The systems reportedly store thousands of data points and provide months of logging via a single coin-cell battery, and it allows for the customizing of logging rate, connections, and alerts.