A communications system comprising a first terminal device and one or more second terminal devices communicating with the first terminal device. The first terminal device is configured to associate at least one content item with a given multimedia file, and to send the content item associated with the multimedia file from the first terminal device to the one or more second terminal devices; and the second terminal device is configured to present the received content item in the second terminal device when a multimedia file having the same content as the multimedia file with which the at least one content item is associated is presented in the second terminal device.