<p>Mobile math trail apps are used to support outdoor mathematics learning, yet empirical evidence on how students perceive specific app features remains limited. This study investigates students’ perception when completing outdoor math trails supported by the mobile app <i>MathCityMap</i>. Using a mixed-methods design, data were collected from 77 students in grades 3 to 8 participating in an extracurricular enrichment programme. Quantitative data were collected using an adapted Technology Acceptance Model (TAM) questionnaire, complemented by open-ended questions that captured students’ positive and negative perceptions. Descriptive analyses and a cluster analysis were conducted to identify patterns of how students perceive mobile learning outdoors. These were subsequently interpreted through qualitative content analyses. Results show a high overall acceptance of the app across all grade levels. Two distinct clusters emerged: one characterized by very high acceptance and a consistently positive attitude towards app-supported math trails, and one showing moderate but still positive acceptance. Qualitative findings indicate that students particularly valued structured task presentation, navigation support, and feedback features such as hints. At the same time, navigation accuracy emerged as the most prominent point of criticism. Furthermore, task characteristics were found to play a central role in shaping students’ perceptions despite technical aspects. Overall, the findings suggest that students’ perception with mobile math trail apps is shaped by the interaction between app features and task design. The study provides empirical insights into students’ perceptions of mobile math trail apps and offers implications for the implementation of outdoor mobile learning environments in mathematics education.</p>