Transient heat conduction and mass transfer have many applications in industry such as heating, cooling, cooking, quenching of steels, freezing, and convective drying of vegetables or fruits. A novel, interactive, and fast MATLAB application, named MULTITHMT, is improved to solve multidimensional transient heat and mass transfer problems. Exact solutions are obtained for infinite rectangular bars, short cylinders, rectangular prisms, and spherical geometries. Instantaneous temperature and moisture content at any location in the objects are obtained and temperature and moisture content at the final time are displayed in two- and three-dimensional graphics. Quenching of steel for rectangle bars and cooking of cylindrical or rectangular prism-shaped meat are represented for transient heat transfer. Cooling of spherical commercial bronze and iron is also investigated. For transient mass transfer, convective drying of rectangular prunes, bananas of short cylinders, and spherical cornelian cherries with different operational conditions is calculated. Drying of cubes with the same shape and different moisture diffusivities is investigated. MULTITHMT is the only program that uses exact solutions to calculate multidimensional heat and mass transfer problems in the available literature. It is also the only application that can calculate the target time with a given temperature or moisture content for any specific location in the studied multidimensional objects. This application can be used for educational purposes in several engineering departments and industrial applications where transient heat and mass transfer processes are needed.