The effectiveness of learning a foreign language via the Duolingo App

This research is conducted to explore the effectiveness of studying online. Among the distance learning practices, there is the Duolingo application to help users learn a foreign language. In particular, this is a case study aiming at exploring whether the Duolingo application is effective enough in learning a foreign language and developing the language skills. The data for this study was collected by research tools such as questionnaires, interviews, and tests, before and after the learning process. 31 candidates participated in this research and talked about their experience. Collecting and analyzing the data of the study distributed into making some assumptions about the application. Taking into account the participants' opinions and suggestions, the researcher managed to identify important issues in the application. The application seems to be effective in the attempt of learning a foreign language. However, there are some issues to be explored regarding the exploration of the language skills and other technical issues on the application. These issues need to be discussed and analyzed for the further improvement of it. Additionally, the researcher gives her opinion by person