Abstract Background Wearable sensors enable patient-led atrial fibrillation (AF) monitoring after catheter ablation (CA). Investigating smartphone ownership and patient behavior may provide insights into wearables research applicability. Understanding engagement and preferences could inform study design and care pathways. Objective To explore smartphone ownership, socio-economic factors, and behavior among individuals screened for the AFFU-AW study; a randomized controlled trial evaluating Apple Watch (AW)-based follow-up after AF CA. The impact of AW provision on patient behavior was also assessed. Methods Patients with AW-compatible iPhone-Operating System (iOS) devices were invited to participate (case arm), while non-enrolled patients served as controls. Demographics, race, and socio-economic status were surveyed at screening. Engagement and perceived impact were assessed in the case arm. Results Of 197 patients screened, 90 (46%) were ineligible due to smartphone incompatibility, 9 (5%) had no household smartphone. Controls were older (62.4±9.2 vs 57.4±9.8, p<0.01) but exhibited no significant gender or ethnicity differences. (table 1) Among AW users, 7 (17%) required additional assistance for device setup, and all subsequently recorded ECGs independently. 23 (57.5%) participants recorded daily ECGs. 30 (73.2%) reported reduced likelihood of seeking medical attention for AF. However, 2 (4%) reported increased likelihood. Participants in the control arm used blood pressure monitors for AF self-monitoring (33.3%). (fig 1). Conclusion Smartphone ownership is prevalent among AF CA patients. Cross-platform compatibility for wearable interventions is important to address potential biases. A majority of patients felt AW monitoring reduced medical attendances, highlighting the potential for wearables to enhance patient-led care. However, a small proportion reported increased health anxiety, indicating a need for tailored support and education.Figure 1:AF monitoring strategyTable 1:Baseline Characteristics