A multimedia device (300, 400), comprising: a receiving unit (310, 405, 1410) configured to receive a broadcast signal; a display unit (351, 480, 1420); and a controller (380, 470, 1430), wherein the controller (380, 470, 1430) is configured: to control the receiving unit (310, 405, 1410) to receive a broadcast signal through each channel available for tuning by serially tuning each channel in the receiving unit (310, 405, 1410) when a first command for executing auto channel tuning is detected, to verify a presence or absence of a first Application Information Table, AIT, in signaling information included in the received broadcast signal of each channel, to, when a second command for executing a first application is detected, extract information on the first application related to a specific channel from the first AIT, when the first AIT exists in signaling information included in a broadcast signal of the specific channel, to execute the first application based on the extracted information, to determine a presence or absence of a link information of a second application based on the executed application, wherein the second application is provided separately from a broadcasting station based upon a network and corresponds to a lower layer application of the first application, to control the receiving unit (310, 405, 1410) to receive a second Application Information Table, AIT, of the second application based on the link information from a respective server through a network, and to store the extracted information on the first application corresponding to the first and second AIT in a memory (360, 440, 1450). a receiving unit (310, 405, 1410) configured to receive a broadcast signal; a display unit (351, 480, 1420); and a controller (380, 470, 1430), wherein the controller (380, 470, 1430) is configured: to control the receiving unit (310, 405, 1410) to receive a broadcast signal through each channel available for tuning by serially tuning each channel in the receiving unit (310, 405, 1410) when a first command for executing auto channel tuning is detected, to verify a presence or absence of a first Application Information Table, AIT, in signaling information included in the received broadcast signal of each channel, to, when a second command for executing a first application is detected, extract information on the first application related to a specific channel from the first AIT, when the first AIT exists in signaling information included in a broadcast signal of the specific channel, to execute the first application based on the extracted information, to determine a presence or absence of a link information of a second application based on the executed application, wherein the second application is provided separately from a broadcasting station based upon a network and corresponds to a lower layer application of the first application, to control the receiving unit (310, 405, 1410) to receive a second Application Information Table, AIT, of the second application based on the link information from a respective server through a network, and to store the extracted information on the first application corresponding to the first and second AIT in a memory (360, 440, 1450). to control the receiving unit (310, 405, 1410) to receive a broadcast signal through each channel available for tuning by serially tuning each channel in the receiving unit (310, 405, 1410) when a first command for executing auto channel tuning is detected, to verify a presence or absence of a first Application Information Table, AIT, in signaling information included in the received broadcast signal of each channel, to, when a second command for executing a first application is detected, extract information on the first application related to a specific channel from the first AIT, when the first AIT exists in signaling information included in a broadcast signal of the specific channel, to execute the first application based on the extracted information, to determine a presence or absence of a link information of a second application based on the executed application, wherein the second application is provided separately from a broadcasting station based upon a network and corresponds to a lower layer application of the first application, to control the receiving unit (310, 405, 1410) to receive a second Application Information Table, AIT, of the second application based on the link information from a respective server through a network, and to store the extracted information on the first application corresponding to the first and second AIT in a memory (360, 440, 1450).