This conceptual study answers how engagement is defined and conceptualized in the mobile service/technology context. A systematic literature review was conducted in the fields of business and human-computer interactions to achieve this objective. The 22 studies included in the final analysis are classified into two categories that distinguish the main perspectives of mobile engagement. This study demonstrates that prior research has either conceptualized mobile engagement as a behavioral activity (i.e., using or interacting with mobile service/technology) or has perceived it holistically as customer engagement that occurs in a mobile environment. Based on the analysis, it is proposed that customer engagement in mobile service/technology context should be understood as a multidimensional concept including behavioral, emotional, and cognitive dimensions. This study contributes to this growing area of research by increasing the understanding about it and proposing a holistic conceptual model of mobile engagement.