With the advancement of information technology, the wireless network and mobile device continue development, which make people can acquire new knowledge with unlimited time and space. Moreover, learners could interact with people or things in real time to truly experience the learning content and situation. Therefore, learning was no longer limited to classroom and time frame. As long as learners had mobile devices in hand and wireless network access, they could be properly guided and receive feedbacks in learning activities according to their learning status and learning environment. Recently, a great number of libraries sense this trend and start to introduce mobile information technologies in library services. They release mobile application services compatible with Internet browsing with mobile devices which allow users linking with libraries and searching for desired information quickly. Therefore, this study developed a 'Mobile Library APP System' and analyzed the usage status, level of satisfaction. The experiment results showed that students' level of satisfaction of 'Mobile Library APP System' had positive correlation, which indicated the system could certainly help them to improve their work efficiency, such as shortened time spent in searching for books and decreased cost of obtaining electrical resources. They also showed the willingness to continue using the system in library relevant activities.