The goal of this clinical trial is to learn if a digitalised Exercise Fit Tool (EFT) mobile application can promote physical activity in adolescents aged 12-18 years who have completed treatment for hematologic cancer (e.g., leukaemia and lymphoma). The main questions it aims to answer are:
1. Is it feasible to conduct a larger randomised controlled trial of the digitalised EFT intervention?
2. Does the digitalised EFT intervention improve physical activity levels, physical activity self-efficacy, and quality of life at 6 months?
Researchers will compare the digitalised EFT intervention group to a usual care group to see if the mobile application can promote physical activity levels, physical activity self-efficacy, and quality of life in adolescents with hematologic cancer.Participants will:
1. Receive a 20-minute educational session on how to use the mobile application
2. Use the mobile application to self-assess their appropriate physical activity level and exercise with a virtual coach
3. Complete questionnaires and wear an accelerometer at 1, 3, and 6 months after enrollment
4. Attend a 20-30-minute individual interview at 6 months (intervention group only, 10 participants)