This study aims to develop pre-service science teachers' skills in designing AR activities and to evaluate the usefulness of BlippAR software. In this context, the study was conducted according to the convergent parallel design, which is one of the mixed research methods. In the quantitative phase of the study, 14 pre-service teachers, all of whom were girls, were included voluntarily. Similarly, the qualitative phase was conducted with 13 volunteer pre-service teachers. Quantitative data in the study were collected using the system usability scale. In addition, qualitative data were obtained using the training evaluation form and written interview form. Then, pre-service teachers' responses to the scale were scored using Excel. Followed by, the scale data were transferred to SPSS and the averages of each item were calculated. The usefulness of the BlippAR software was evaluated through the related data. On the other hand, the qualitative data obtained from the written interview form were transferred to the MaxQda 2020 program and subjected to content analysis. When the quantitative and qualitative data are evaluated together, it can be stated that the BlippAR system is not complex and the functions are integrated systematically. In line with all the aforementioned feedback, it can be inferred that the BlippAR system is useful but needs some improvements. In this context, it can be aimed to add new system functions, diversify the language options, and enrich the library.