Life jacket is one of the safety appliances that can be found on the ship that provide buoyancy and prevention against drowning. Before the ship can sail, every element of safety of the vessel should be confirmed. Despite the establishment of standards for life jacket, both local and international, there have been cases of drowning associated with the usage of life jackets by the passengers of passenger boat/vessels for open-deck situation. Moreover, deficiency of information on safety instruction is reason the passengers are lack of personal safety information during on board. Thus, the evaluation on safety standard of life jackets and passenger vessel are vital for assessing the provision of the life jacket on board passenger vessel with respect to compatibility between life jacket and passenger vessel. In this paper, A Vessel Life Jacket Compatibility Mobile Apps (VELIT) was developed using software development methodology called Rational Unified Process (RUP) to automate the safety assessment process based on model called LCI (Life Jacket Compatibility Index). VELIT apps synchronized the safety assessment aspect and which allow user to compute the element in the model and produce the result of the safety assessment in real time. The VELIT apps are expected to be used in maritime area especially for ship safety assessment process.