Mobile device polling is disclosed. A content polling system includes a content polling module configured to transmit a content polling request to participant mobile devices that is executable by each participant mobile device to return a content polling response to the content polling module. The content polling module is further configured to receive the content polling response from each participant mobile device that indicates an attribute of one or more media content items stored at or previously accessed via that participant mobile device. The content polling module is further configured to transmit a content selection request to a content selection module that indicates the attributes of the content polling responses. The content selection request is executable by the content selection module to return a content selection response indicating selected media content that was selected by the content selection module based on the attributes indicated by the content selection request.