The mobile application, Baicizhan, is a useful tool for Chinese students to learn English vocabulary. Research in mobile application use in English vocabulary learning is still in its infancy. This book aims to investigate Chinese students' responses towards Baicizhan use in learning vocabulary. This investigation was carried out by reviewing existing literature and self-evaluating with a checklist. The students' responses to Baicizhan were sought through questionnaires and interviews. The results showed that most students responded to the overall design of Baicizhan positively. Using pictures to help learners learn vocabulary made it stand out. Also, students tend to strongly agree or agree that Baicizhan, as a mobile application, help them with their vocabulary to some extent. They can learn vocabulary with their smartphones rather than books or dictionaries. The mobility of smartphones enables them to learn vocabulary without limitation of time and places. However, there are still some improvements can be made on learning activities in Baicizhan. This implies that it is necessary to progress Baicizhan so that students can make better use of it.