Mixed reality (XR) environments combining real-to-virtual immersive experiences provide unprecedented potential for reframing educational pedagogy and practice. XR environments provide scaffolded learning points accommodating individual needs, while enhancing sensorial and embodied experiences. XR environments can facilitate self-determined (heutagogical) experience-based learning and esthetic visualization of wicked problems, making complex knowledge more accessible. Here we report on a study exploring the design of mobile learning with education outside the classroom (EOTC), heutagogy, and free-choice learning to enhance marine ecological literacy, based on a bring your own device (BYOD) XR intervention at a marine educational center in Aotearoa New Zealand. Findings indicate that XR affordances can enhance the understanding of complex marine conservation science, facilitating ecological literacy knowledge, attitudes and behavior change. Implications include pedagogical rethinking of EOTC with self-determined mobile learning; haptic, sensorial and embodied XR design considerations for environmental education; and epistemological speculation on learning phenomena in real-to-virtual immersive environments.