Mobile devices are now widely owned and available to the majority of people. While the affordances of mobile learning include supporting a more personalized, authentic, situated learning based on the findings of many studies, it is crucial and urgent to start rethink pedagogy and learning using mobile devices. Additionally, as the concept of augmented reality (AR) enables learners to receive additional, valuable information in a real setting, this study, thus, aims to investigate the effects of a mobile-based augmented reality simulation learning system for English vocabulary acquisition on learners of different learning styles (field independence/dependence, FI/FD) and English proficiency (high/low) in terms of learning outcome and motivation. An experimental research design was used in this study to identify any differences between FI, FD students and high/low English proficiency learners. The results showed that FD learners benefitted significantly from the mobile AR instruction on learning outcome; there was a borderline significant difference between high and low English proficiency learners on learning outcome; and neither learning styles nor English proficiency affected learning motivation after the mobile AR instruction was applied. From the findings of the present study, individual differences should be considered when a new instructional approach is applied in order to make learning more effective and motivating.