An in-vehicle infotainment system comprising: a first device included in a vehicle, and comprising a first memory; a second device electrically connected to the first device, attachable or detachable to the vehicle or from the vehicle, and comprising a second memory; and an interface configured to electrically connect the second device to the first device, wherein in response to execution of a first application, the second device is configured to generate first data including user-customized data and transmit the generated first data to the first device, wherein the first memory stores the first data including the user-customized data, the second device executes the first application based on the first data, and the first application is stored in the second memory, wherein the user-customized data includes login information of the first application or a user profile information, wherein in response to the second device being replaced with a third device comprising a third memory, the first device is configured to transmit the first data including the user-customized data to the third device, wherein the first device is configured to check whether an operating system of the second device is equal to an operating system of the third device, and in response to the operating system of the third device being not equal to the operating system of the second device, transmit data including an application list received from the second device to the third device, wherein the third device is configured to compare applications in the application list with applications installed in the third device, request an application which does not exist in the application list, receive and install the requested application. a first device included in a vehicle, and comprising a first memory; a second device electrically connected to the first device, attachable or detachable to the vehicle or from the vehicle, and comprising a second memory; and an interface configured to electrically connect the second device to the first device, wherein in response to execution of a first application, the second device is configured to generate first data including user-customized data and transmit the generated first data to the first device, wherein the first memory stores the first data including the user-customized data, the second device executes the first application based on the first data, and the first application is stored in the second memory, wherein the user-customized data includes login information of the first application or a user profile information, wherein in response to the second device being replaced with a third device comprising a third memory, the first device is configured to transmit the first data including the user-customized data to the third device, wherein the first device is configured to check whether an operating system of the second device is equal to an operating system of the third device, and in response to the operating system of the third device being not equal to the operating system of the second device, transmit data including an application list received from the second device to the third device, wherein the third device is configured to compare applications in the application list with applications installed in the third device, request an application which does not exist in the application list, receive and install the requested application.