How to shifting consumer behavior to be more sustainable has been a hot research topic. The COVID-19 Pandemic has ignited this since consumers pay more attention to sustainability issues. Sustainability application (app) has been a promising way to connect individuals and provide information to promote a habit of sustainable consumption. The use of these apps to facilitate sustainable consumption has been a recent research focus. The strategy to encouraging app adoption is a research priority identified in a synthesized literature review of prior studies on mobile app marketing. As such, it is imperative to understand how to design sustainability apps to motivate consumers to facilitate app use intention. Attention, relevance, confidence, and satisfaction (ARCS) model is one commonly used motivational design model, which has been applied to mobile learning systems to examine gamification design. The four factors of ARCS correspond to different strategies to increase users’ motivation to use the app. Thus, the aim of this research is to develop an ARCS motivational model for sustainability apps. A simulated gamified sustainability app was utilized with the aim of reducing carbon footprint. A market research firm was contracted to collect data by using an online questionnaire. Respondents were shown the pictures and functions of the app including the interface of the app, carbon footprint status, the leaderboard of carbon emissions in the community, shop, personal profile and then answered questions. 346 usable questionnaires were obtained. Partial least squares structural equation modeling was used to analyze the data.