This article reports on an exploratory study on developing and adopting a 'Virtual Go Mode' feature embedded in a mobile vocabulary learning app, VocabGo, to enhance students' vocabulary learning engagement. Distinguished from other virtual reality (VR) or augmented reality (AR) applications, the Virtual Go Mode is designed for students to practice and consolidate their newly learned words via virtual location-based tasks with 360° Google Street View or pre-photographed panoramas. Google Cloud Vision, using an AI model, is embedded to identify objects and their corresponding tasks for students. A total of 15 primary students in Hong Kong participated in this exploratory study for one week. Both quantitative and qualitative data were collected and analyzed. The results showed that students' vocabulary learning engagement was high when using the Virtual Go Mode. It is suggested that future research focus on empirical studies when designing and implementing virtual location-based tasks supported by VR technologies in class to provide opportunities for students to practice and consolidate newly learned words and enhance their learning engagement after the COVID-19 pandemic.