Testo 0560 1905 905i smartprobe bluetooth air thermometer testo 0560 1905 p the compact testo 905i professional thermometer in conjunction with a smartphone or tablet is ideal for measuring ambient temperature as well as temperatures in ducts and at air outlets p p the innovative testo smartprobe range can be connected to your smartphone or tablet and with the free testo smart probes app installed on your bluetooth device you can view your readings conveniently all measurement data is