J-Thermo is an thermometer that plugs into audio jack of your iPhone/iPad. Features: -Plug and Play! No setup required -Measurement range from -50 to 150 °C (-58 to 302 °F) -125 mm stainless steel sensor probe -Real-time temperature measurement in both °C and °F -Highest, lowest temperature display -No battery required. -Temperature higher than 150 °C or 302 °F is treated as HH.H. -Temperature lower than -50 °C or -58 °F is treated as LL.L. How to use: 1. Open "J-Thermo" app. 2. Firmly plug the J-Thermo into the audio jack of iPhone/iPad and turn the headphone volume to maximum.The temperature reading shall be shown in a few seconds. 3. When you finished using J-Thermo, press "Done", then plug out J-Thermo from iPhone/iPad. (Please make sure the app is opened when the iPhone/iPad is in portrait mode, otherwise the UI will be abnormal. An update will be released soon to fix this.) Troubleshooting: If the J-Thermo is not showing the temperature reading, please check the following: -If the app shows "No J-Thermo detected" or "No data from J-Thermo", please manually turn the headphone volume to maximum. -If the app shows "Cannot access microphone due to privacy setting", then please turn ON the microphone accessibility in privacy setting for "J-Thermo" app. -Please make sure "Volume Limit" is turned off in "Settings" of iPhone/iPad. -For iPhone/iPad purchased in EU, the EU volume limit may apply to devices which means the headphone volume maybe lower, therefore it is not guaranteed that J-Thermo will work. If there is "EU Volume Limit" in "Settings", please turn it off and try. Contact us: If you have any enquiries, please contact marco@carrin.com.hk