Inclusion Criteria:  Those who have been diagnosed with colorectal cancer and have undergone surgery (not related to chemotherapy treatment) Patients aged 19 to 75 years old Those who can use prognosis management applications and can perform regular follow-up inspections outpatients Patients carrying Android or iOS smartphones Patients who voluntarily decide to participate and give written consent after hearing detailed explanations about this study  Exclusion Criteria:  Those who are judged to be difficult to perform smartphone exercise and dietary management for colorectal cancer in general due to uncontrolled severe or underlying diseases, neuromuscular and musculoskeletal diseases Serious complications of Clavein dindo classification grade 3 or higher after surgery Patients who were not discharged within 2 weeks after surgery