Abstract Few studies have investigated quality of life (QoL) improvements in patients with colorectal cancer or the benefits of digital healthcare interventions. This randomized controlled trial assessed the impact of mobile applications on postoperative QoL in patients scheduled for curative surgery for colorectal cancer. Patients were randomized into three intervention groups (each using a different mobile application for postoperative lifestyle management) and a control group. QoL was evaluated using the European Quality of Life-5 Dimensions (EQ-5D), with physical and metabolic parameters and fat/muscle areas measured preoperatively, and every six months postoperatively. At six months, no significant differences in the EQ-5D scores from baseline were observed across groups. Intervention Group C showed a significant increase in skeletal muscle area compared to the control group (P = 0.046). Overall, mobile application use had a minimal effect on postoperative health-related QoL, warranting further research on their efficacy and compliance rates. Trial registration: CRIS.nih.go.kr: KCT0005447. Registration date: June 23, 2020.