1. A prototype of graphical user interface (GUI) application creation method comprising: receiving, through a prototype creation interface of a prototype creation terminal, a selection of a title of a first layer from a list of titles of plurality of layers displayed in the prototype creation interface; receiving a selection of a first trigger through the prototype creation interface, which triggers an output of a specific response to be displayed in a prototype execution terminal, wherein the first trigger is displayed with information of a first action to be recognized as a triggering input; receiving a selection of a 1-1st response of the first trigger through the prototype creation interface, wherein the 1-1st response is an output to the first layer driven by the prototype execution terminal when the first trigger is initiated by a user of the prototype execution terminal; receiving an input of a timeline of the 1-1st response through the prototype creation interface; receiving a selection of a second trigger through the prototype creation interface, wherein the second trigger is displayed with information of a second action to be recognized as a triggering input; receiving a selection of a 2-1st response of the second trigger through the prototype creation interface, wherein the 2-1st response is an output to the first layer driven by the prototype execution terminal when the second trigger is initiated by the user of the prototype execution terminal; receiving an input of timeline of the 2-1st response through the prototype creation interface; in response to receiving the input of timeline of the 1-1st and 2-1st response, generating a prototype, by applying 1-1st response and 2-1st response to which the timeline is input, to the first layer through the prototype creation interface; displaying the list of titles of plurality of layers, the first trigger, plurality of responses associated with first trigger including the 1-1st response, the timeline of the 1-1st response, the second trigger, plurality of responses associated with second trigger including the 2-1st response, and the timeline of the 2-1 response adjacent to each other through the prototype creation interface, and displaying the first layer which is a preview image of the GUI application to which the 1-1st response and the 2-1 response is applied, with the adjacently displayed list of titles, first trigger, plurality of responses associated with first trigger including 1-1st response, timeline of the 1-1st response, second trigger, plurality of responses associated with second trigger including 2-1 response, and the timeline of the 2-1 response, simultaneously in one screen; transmitting, by a prototype creation terminal, the generated prototype to the prototype execution terminal; and executing, by the prototype execution terminal, the transmitted prototype to be displayed on the prototype execution terminal.