This study applied a qualitative method to investigate Saudi students' perspectives on the effectiveness of using the WhatsApp application to support their learning and interaction in online courses. A purposive sample including eight Saudi pre-service teaching students (three males, five female) was selected from the College of Education at King Faisal University (KFU) in Saudi Arabia. These participants were interviewed face-to-face using a semistructured interview technique. Member-checking and peer review strategies were used to check the trustworthiness of the findings. After the data was analyzed, two themes emerged: (1) the effectiveness of using the WhatsApp application and (2) the critical challenges involved in the usage of the WhatsApp application in an academic context. The effectiveness of using the WhatsApp application in this context includes (1) convenience and practice, (2) communication, (3) material sharing, (4) course information sharing, and (6) ease of use. The tendency for instructors to ignore student questions and a lack of interaction rules represent the critical challenges involved in the usage of WhatsApp in an educational context. Several recommendations were made based on the results of this study.