An expandable socket for attachment to a mobile electronic device. The expandable socket includes a platform adapted to engage a portion of the portable media player, a skin coupled to the platform, wherein the skin is deformable between a collapsed configuration and an expanded configuration. The expandable socket includes a button coupled to the skin opposite the platform. The expandable socket also includes a biasing element arranged within the skin between the platform and the button, the biasing element configured to bias the skin into the expanded configuration.