Mobile technologies open up new ways of fostering reflection in teacher education. With the intention of tying reflection closer to the actions in the classroom, facilitating multimedia recordings, providing prompts for reflection and fostering discussions between pre-service teachers, experienced teachers and university mentors, we developed the "Metapholio" app and tested it in the context of teaching internships. This app supports pre-service teachers in collecting noteworthy moments in the classroom by providing functionalities for individual and collaborative note taking. Notes can be created in the form of written text, photography, audio recordings and video recordings. Each note can be commented on and discussed with invited peers, experienced teachers and university mentors, who can also record moments themselves. Furthermore, the app makes it possible to select notes and attach them to more general written or spoken reflections on teaching and learning. Theoretical frameworks and writing prompts that are part of the app serve as scaffolds for such reflections. Peers, teachers and mentors can be invited to join the conversation on reflections. With the help of this app, pre-service teachers can, moreover, create their own multimedia mobile portfolio, which acts as a hybrid space for professional development in teacher education.