This study is a longitudinal study that adopts a double-blind randomized controlled trial (RCT). The study will recruit 120 male nurses and allocate them into the intervention group and the control group in a 1:1 ratio (60 in each group). Based on Super's (1957) career development theory and the four-stage career classification, the participating male nurses will be divided into the exploration stage (experience ≤ 2 years), establishment stage (experience 2-5 years), and maintenance stage (experience 5-15 years), with career stage as a confounding factor. The study uses 1:1:1 stratified randomization to ensure that the number of cases in the experimental group (n=60, exploration stage: establishment stage: maintenance stage = 20:20:20) and the control group (n=60) is the same, as well as the homogeneity of the career stage variables of the two groups. All included subjects will undergo an online pre-test (T0) before allocation, and then enter the experimental group or the control group according to the random assignment results. Both groups will be invited to use the "Building Your Successful Nursing Career" App for six months, with the experimental group receiving the full career planning mobile application intervention and two online Career Mentoring Programs, while the control group receives a sham treatment. Both groups will undergo five follow-up online data collections (0, 6, 12, 18, and 24 month post-intervention). The effectiveness of the career planning mobile application intervention on male nurses' career self-efficacy, career adaptive behaviors, occupational resilience, career success, and career continuity intentions will be examined using the intention-to-treat analysis method and General Estimating Equations (GEE).
