 This systematic review assesses the characteristics of smartphone-delivered ecological momentary interventions, EMICE, using self-reported ecological momentary assessments, EMACE, in relation to their effects on health behaviors, user engagement, and user perspectives. The results show that EMICE are most popular in the mental health domain, and have been found to be helpful by users. However, there is great heterogeneity in intervention designs and measurements, and further assessment in larger participant cohorts, and well-designed evaluations following reporting checklists is needed to determine their efficacy. The review suggests combining self-reported EMACE of subjective experiences with objective data passively collected via sensors to promote personalization while minimizing user burden, as well as exploring different EMA data collection methods example chatbots. This article was authored by Kim Foong Dao, Katrina Cocker, Hong Laitong, and others.