This study investigated the effects of using self-developed mobile APP and Arduino in English vocabulary learning, to find out the impact on students’ vocabulary learning ability, to understand students’ perception of such learning patterns, and to evaluate the feasibility of lower graders using APP in English vocabulary learning. Arduino was adopted to be associated with APP to provide integrated multimedia support. The study adopted Single Subject Research Design. Five first graders from New Taipei City Taiwan were selected and the experiment was conducted for 10 times in 8 weeks. Data were collected through testing, observation, interviews and questionnaires. The results showed that self-developed English learning APP has a positive impact on students’ vocabulary learning ability. Students gave positive response and held positive attitude toward English learning through APP. Students were willing to learn with English learning APP and enjoy learning. The integration of English learning and APP and Arduino was addressed and hoped to broaden the spectrum of English learning design in mobile devices.