A case for an electronic device includes a shell and at least three electrical connectors. The shell receives the electronic device and covers at least a portion of the electronic device. A first electrical connector is on an interior of the shell and electrically connects the case to an electrical interface of the electronic device when the electronic device is installed in the case. A second electrical connector is on an exterior of the shell and electrically connects a first external electrical device to the electronic device through the electrical interface of the electronic device. A third electrical connector is on the exterior of the shell and electrically connects a second external electrical device to the electronic device.