dot thermo external - thermometer | temperature sensor | temperature data logger | direct wifi connection with text message & email alarms | compatible with iphone + android + pc dot-01 thermo external is a wifi temperature recorder and alarm system with an external sensor. it is powered by 2 replaceable aa batteries for up to 10 years and connects directly to wi-fi. more than an accurate meter and a reliable logger, dot thermo external is also a cloud-based alarm system. all setting parameters like measurement intervals, upload intervals, minimum, and maximum allowed temperature thresholds can be set through a web-based application on any platform. it sends out email and text message alarms as soon as temperature exceeds or falls below preset limits. it also provides access to the records history, graphs, and periodical reports. its hardware and software installation is very easy and does not require any specific tools or applications.