The use of social media facilitates communication and collaboration among users to support the student-centered learning environment. In this study, Twitter was used to support blended learning activities in two university courses. A survey was conducted and the results showed that Twitter was easy to use and it could facilitate knowledge sharing among different learners. However, the text-based communication for a relatively simple exchange hindered the interaction among learners. Moreover, students preferred using social media such as Facebook with a higher degree of popularity.