Gummi is an interaction technique and device concept based on physical deformation of a handheld device. The device consists of several layers of flexible electronic components, including sensors measuring deformation of the device. Users interact with this device by a combination of bending and 2D position control. Gummi explores physical interaction techniques and screen interfaces for such a device. Its graphical user interface facilitates a wide range of interaction tasks, focused on browsing of visual information. We implemented both hardware and software prototypes to explore and evaluate the proposed interaction techniques.Our evaluations have shown that users can grasp Gummi's key interaction principles within minutes. Gummi demonstrates promising possibilities for new interaction techniques and devices based on flexible electronic components.