Online courses provide flexibility and convenience for students and have become very popular in recent years. With the advance of technology and change of habits for the uses of traditional communication tools among students, there is a need for educators to explore effective ways to communicate with students that fit their social-media life styles. Two communication tools--web-based text messaging via cellular phone and real-time webinar software--were implemented in a fully online preparatory chemistry course with a full-time working student body. The text messaging system allows the instructor to send short text messages directly to all students' cellular phones while keeping the students' phone numbers anonymous. Important announcements and information were texted to the students' phone number throughout the course. In addition, the instructor conducted individual appointments with each student via webinar software. The number of students who contacted the instructor for course-related inquiries increased 25% after the webinars and 96% of the students turned in all the assignments on time. With the implementation of these two communication tools, the drop-out rate of the course was decreased by 42%. It was concluded that these tools enhanced student engagement and increased the retention rate.