The aim of this study is to know the effect and implications of the Mobile Seamless Learning Strategy on students' concept mastery ability. The research conducted at an Elementary School in Jepara Central Java, Indonesia. The study was quantitative using a quasi-experimental with non-equivalent control group. The participants were student IV class. Subject were selected by classing cluster random sampling. As a results of study, implementation of the mobile seamless learning strategy had a significant impact on students' concept mastery ability. Mobile seamless learning also has advantages 1) students are able to learn unlimited classrooms and time, 2) students can learn anytime and anywhere, 3) integrated learning between formal education and non-formal education, 4) students are digital native so they are very familiar with the world of mobile phones, 5) students can learn both personally and socially, 6) students are able to learn both digitally and physically.