Digital health treatments for individuals with behavioral health problems are increasing rapidly in number.1,2 Studies to date have demonstrated that longitudinal patient engagement is challenging,3,4 making it unlikely for most applications (hereafter, apps) to effect real-world change. In this cross-sectional study, we describe usage patterns of popular mobile behavioral health apps and identify characteristics of those that are most continually accessed (also known as the stickiest),5 with the aim of informing future research on behavioral health app engagement
