The Umwelt Apparatus is a design exercise in which designers attempt to build a device that would help them experience the world from the perspective of different animal species. It is rooted in a tradition of empathic design, where designers use various techniques to get closer to the lives and experiences of existing or future users to gain a deeper understanding of their experience in the world. In the Umwelt Apparatus exercise, this approach is extended to learn about nonhuman species and the manifold ways in which they interact and experience the world, with the subsequent aim of including these perspectives in the practice of design.