Pneumonia is a respiratory disease with a high prevalence in Indonesia. Determination of pneumonia levels is done by radiology examination, physical examination and clinical history. If the determination of the level of pneumonia is not right, it will affect the treatment and subsequent treatment. The purpose of this study is to design an android application that can be used to determine pneumonia levels. The device was built using 9 input parameters in the form of standard inspection results for the diagnosis of this disease. The classification method uses the Dempster-Shafer algorithm which has been equipped with a belief value for each parameter. The device output consists of 2 classes, namely mild pneumonia or severe pneumonia. Through the device performance tests obtained sensitivity, specificity and accuracy of 85%, 94.29% and 90.90%.