A relay device comprising: a first interface configured to connect to a portable computing device; a second interface configured to connect to an accessory; and a controller coupled to the first and second interfaces, the controller being configured to: communicate with the portable computing device via the first interface in accordance with an accessory protocol; detect a connection of the accessory to the second interface; notify the portable computing device that the accessory has become connected to the second interface; receive a first command from the portable computing device, the first command including a second command, the second command including data intended for the accessory; determine whether the first command is a data sending command; in response to determining that the command is not a data sending command, process the first command; and in response to determining that the command is a data sending command: extract the second command from the first command; and relay the second command to the accessory; wherein the first interface includes a first connector and the second interface includes a second connector complementary to the first connector. a first interface configured to connect to a portable computing device; a second interface configured to connect to an accessory; and a controller coupled to the first and second interfaces, the controller being configured to: communicate with the portable computing device via the first interface in accordance with an accessory protocol; detect a connection of the accessory to the second interface; notify the portable computing device that the accessory has become connected to the second interface; receive a first command from the portable computing device, the first command including a second command, the second command including data intended for the accessory; determine whether the first command is a data sending command; in response to determining that the command is not a data sending command, process the first command; and in response to determining that the command is a data sending command: extract the second command from the first command; and relay the second command to the accessory; wherein the first interface includes a first connector and the second interface includes a second connector complementary to the first connector. communicate with the portable computing device via the first interface in accordance with an accessory protocol; detect a connection of the accessory to the second interface; notify the portable computing device that the accessory has become connected to the second interface; receive a first command from the portable computing device, the first command including a second command, the second command including data intended for the accessory; determine whether the first command is a data sending command; in response to determining that the command is not a data sending command, process the first command; and in response to determining that the command is a data sending command: extract the second command from the first command; and relay the second command to the accessory; in response to determining that the command is not a data sending command, process the first command; and in response to determining that the command is a data sending command: extract the second command from the first command; and relay the second command to the accessory; extract the second command from the first command; and relay the second command to the accessory; wherein the first interface includes a first connector and the second interface includes a second connector complementary to the first connector.