At least some aspects of the present disclosure feature a mobile sensing system comprising a sensing device for measuring a thermal property of an object, comprising an RF circuit and an antenna electronically coupled to the RF circuit, a sensor electronically coupled to the RF circuit, and a thermal source thermally coupled to the sensor and electronically coupled to the RF circuit, a mobile device having a processor, an RF reader connected to or integrated with the mobile device, wherein the RF reader is configured to interrogate the sensing device; wherein the sensing device receives power when the RF reader interrogates the sensing device and provides at least a portion of the power to the thermal source.