E-textile is a developing technology joining the advantages of material science and information and communication technologies. In this work, we present the development and assessment of smart textile system containing sensing, processing and wireless communication capabilities. We demonstrate a wearable temperature sensing system based on resistance temperature detection approach utilizing graphene technology, which allows high flexibility and robustness of the electronic textile. The developed sensing system demonstrates experimental sensitivity as high as 80Q/°C within the temperature detection range from 24 °C to 35 °C, which is the highest reported to date for wearable temperature sensors. In terms of wireless communication, the system operates at 2.4 GHz supporting Bluetooth low energy technology and securely transmits the measured data for up to 10 m which is proved by received signal strength and link quality indicators.