While e-books offer great potential for academic libraries, research has shown that usability issues can prevent readers from reading e-books or from using certain ebook functions. This study presents the results of usability testing on the platforms of three of the largest aggregators of academic e-books: ebrary, MyiLibrary, and Ebook Library. In addition to learning about the usability of these specific platforms, this research provides greater insight into the usability issues that students encounter while reading e-books and a deeper understanding of how e-books can meet the academic needs of students. Five undergraduate and five graduate students participated in testing, completing a series of tasks in each platform. Testing revealed several usability issues. Students want flexible navigational options, including the ability to scroll. Additionally, students enjoy certain e-book features, such as annotation and highlighting tools, but they were not sure that they would use these tools.