Japanese university English instructors are increasingly requiring students to use their personal smartphones for activities in English as a Foreign Language (EFL) classroom activities. Because of this, it has been recommended that studies be conducted to ascertain Japanese university students' perceptions of using smartphones in EFL language learning. The problem that this study addressed is that several studies have demonstrated Japanese university EFL teachers require students to use their smartphones to perform language learning activities, but little is known about student perceptions of using their own smartphones for EFL activities. The purpose of this qualitative, single case study was to explore Japanese university students' perceptions of required use of personal smartphones in EFL classes. Purposeful sampling was used to gather a sample of nine students from a sampling frame from one university EFL class at one public university in northern Japan. Data collection employed in-depth interviews to gather college student experiences with being required to use their personal smartphones in the EFL course. Secondary data was gathered by collecting nonverbal cues observed during the interviews to confirm the students' feelings as expressed in their verbal interview responses. This study was grounded in a thorough review of the literature that identified a need for further exploration of Japanese university student perceptions of using their personal smartphones in their EFL classes. The results of this study showed that Japanese university students have had little experience with using their smartphones for language learning activities, but that they enjoy and prefer that their professors require them to use their smartphones in EFL class activities. They feel that EFL classes which take advantage of student smartphones are more interesting and more productive because of the affordance of individualization of instruction. This study provides Japanese universities' EFL educators insight into student perceptions of current educational trends, and the results provide insight into how those trends may affect students' motivation. However, because this study was limited in size, replication studies should be conducted to thoroughly understand student and teacher preferences in using smartphones in EFL learning and to make EFL education in Japanese universities as efficient and effective as possible. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]