Document Type


Journal/Book Title/Conference


Publication Date


First Page


Last Page



There is growing evidence for the efficacy of acceptance and commitment therapy (ACT) interventions delivered through smartphones, but research has not yet focused on how to optimize such interventions. One benefit of mobile interventions is the ability to adapt content based on in-the-moment variables. The current randomized controlled trial evaluated whether an ACT app that tailored skill coaching based on in-the-moment ecological momentary assessments (EMAs) would be more efficacious than the same app where skill coaching was random or an EMA-only condition. A sample of 69 adults interested in using a self-help app were randomized to one of three app conditions and used the app for the following four weeks. Results indicated equivalently high user satisfaction with the tailored versus random apps. Participants used the EMA-only app the most and the tailored app the least, but overall adherence was adequate. Participants in the tailored app improved significantly more on psychological distress and positive mental health relative to the random app and EMA-only conditions. However, no differences were found between the random app and EMA-only conditions on outcomes. Between group differences over time were also found on psychological inflexibility, but this appeared to be primarily due to a lower rate of improvement in the random app condition relative to both tailored and EMA-only. Overall, these results suggest that tailoring ACT skill coaching based on in-the-moment variables leads to greater efficacy.