Publicly available acceptance and commitment therapy mobile apps: Systematic search and assessment

Acceptance and commitment therapy (ACT) is a third-wave cognitive behavioral therapy with demonstrated effectiveness across a range of mental health conditions. Healthcare professionals, researchers, and commercial developers have identified mobile health technologies as a promising avenue for expanding access to ACT. Despite the emergence of ACT-based smartphone apps, no studies have systematically evaluated their content, usability, and theoretical fidelity. The absence of standardized evaluation frameworks limits their clinical integration and the potential for iterative improvement. This study aimed to systematically assess the features, functionality, theoretical congruence, and data privacy practices of publicly available, ACT-based mobile apps, designed for independent or adjunctive use, available in major app stores. A systematic search was conducted in January 2025 using AppTweak to identify ACT-based apps in the Canadian Apple App Store and Google Play Store. Apps meeting the inclusion criteria were downloaded and assessed on either a Samsung Galaxy A15 (Android 14) or iPhone 13 (iOS 17.6.1). Eligible apps included those offering ACT content for independent use or recommended use alongside therapy, without requiring therapist facilitation. A custom assessment framework consisting of 49 criteria was developed by the research team to evaluate general characteristics, ACT fidelity, and technical quality. The Mobile App Rating Scale (MARS) was used to assess usability. Data extraction and ratings were conducted independently by two reviewers. The results were reported as a narrative review using descriptive statistics. The initial search yielded 200 apps, of which 17 met the inclusion criteria and were systematically assessed. All apps addressed at least one ACT process, with all apps covering acceptance, present-moment awareness, and committed action to varying degrees. The average MARS score across the apps was 3.63, with app engagement rated the lowest across apps. Most relied heavily on text-based content and psychoeducation, journaling, and guided meditations, with limited use of highly interactive or visual modalities. While most apps offered an accessible privacy policy, fewer were transparent about third-party data sharing practices. Clinician involvement in app development was common. Importantly, no apps had published peer-reviewed evidence of effectiveness. Publicly available smartphone apps show promise for delivering ACT-related content at scale, whether as standalone tools or companions to ongoing therapy, but vary widely in theoretical fidelity, user engagement, and transparency of privacy policies. Most apps lack scaffolding to support skill development across the ACT processes and do not leverage multimedia or interactive design to enhance experiential learning and engagement. These findings highlight the need for evidence-based, user-centered ACT app development informed by cognitive learning principles. This review provides a preliminary framework for future evaluation and design of ACT digital tools in the evolving mobile health landscape. • First review of publicly available apps based on Acceptance and Commitment Therapy. • Evaluated content, features, and usability of 17 apps in major Canadian app stores. • Novel application of framework to assess fidelity of app content to core processes. • Engagement scores were lowest, reflecting basic interactivity and text-heavy content. • No apps had peer-reviewed evidence of effectiveness indexed in PubMed database.