A method and device for providing content are provided. The method includes receiving a connection request from a mobile device; connecting to the mobile device based on the connection request; obtaining, from the mobile device, identification information of the mobile device, application information of an application running on the mobile device, and content information about the content to be processed by the application; transmitting the identification information, the application information, and the content information to a casting device capable of performing cellular data communication; obtaining the content from the casting device; and outputting the content, wherein the content obtained from the casting device is received by the casting device through a cellular data communication network based on the content information and processed based on the application executed on the casting device.