A Multi-language Smartphone-based Healthy Lifestyle Intervention for Firefighters

The goal of this cluster randomized controlled trial is to evaluate the effects of a smartphone-based Healthy Lifestyle (HLS) intervention on firefighters' mental and physical health in firefighters in Tainan, Taiwan. The main questions it aims to answer are: * Does the Traditional Chinese version of the HLS mobile App improve firefighters' mental and physical health compared to usual care? * Can the intervention effectively promote a healthy lifestyle and reduce the risk of chronic non-communicable diseases among firefighters? Researchers will compare firefighters receiving the smartphone-based HLS intervention to those receiving usual care to determine whether the intervention leads to improved health and fitness outcomes over 3 to 6 months. Participants will: * Use the Traditional Chinese version of the HLS mobile App, originally developed at Cambridge Health Alliance, Harvard Medical School, and adapted for firefighters in Taiwan. * Be randomly assigned to either the intervention group (HLS App) or the control group (usual care). * Undergo health and fitness assessments at baseline and at 3 to 6 months post-intervention. Anticipated outcomes are improvements in mental and physical health among firefighters receiving the intervention compared to the control group.