Mobile learning application for assisting teachers or preservice teachers to develop questions based on higher-order thinking skills had not been widely invented. Thus, this study aimed to develop EduQuestioning mobile learning application that could help teachers or teacher candidates create assessment questions based on higher-order thinking skills (HOTS). The present study used research and development design by involving developmental stages of analysis, design, development, implementation, and evaluation (ADDIE). This study involved qualitative and quantitative data. There were eight lecturers and sixty-one preservice teachers majoring in mathematics, natural science, social science, and Indonesian language education involved as the participants. They were chosen using inclusion criteria such as being involved in assessment course. Data were collected using forum group discussion, student-needs analysis questionnaire, Aiken and Expanded Gregorian Index content validity sheet, face validity sheet, and structured response questionnaire. The obtained qualitative data were analyzed using Miles and Huberman’s theory and the quantitative data were analyzed using descriptive statistics and Swanson’s quartile categorization. Results showed that EduQuestioning mobile learning application could be developed through ADDIE stages with a very high content and face validity. In addition, the participants gave positive response on the use of EduQuestioning with M% > 75% and Q = 4. This study suggested that EduQuestioning mobile learning application could be accessed freely and used to train developing HOTS-based learning assessment questions.