The useful application for tablets and smartphones that Rotax makes available to better adjust the carburetion of its kart engines has recently been updated. Available directly both on Google Play (for Android) and on the App Store (for Apple devices) and now in release 2.0.2, this application can be downloaded and installed for free and easily on your device (also via the attached QR codes) and is provided in English or German. By entering the data of the atmospheric conditions measured on the track or obtained from the nearest meteorological survey center (identified by GPS), such as temperature, altitude, humidity and atmospheric pressure, the theoretically best measure for the main jet is indicated, leaving little margin of error (and the possibility of “fine” adjustment through the needle and screw) in the search for the best calibration. This applies to all types of thermal engines that run in the wellknown Rotax Challenge (from Mini to DD2) in any environmental condition.