An electronic device comprising: a housing; a physical display exposed through a portion of the housing; at least one processor positioned inside the housing and operatively connected to the physical display; a first buffer configured to store 2 dimensional, 2D, graphic data output from a first application associated with a 2D user interface; a second buffer configured to store 3 dimensional, 3D, graphic data output from a second application associated with a 3D virtual reality, VR, environment; a third buffer configured to store the 2D data or the 3D graphic data as if the 2D graphic data or the 3D graphic data were being displayed on the physical display; wherein, in case that the electronic device is in a first operation mode in which the electronic device operates as a mobile device, a first output path of the first buffer and a second output path of the second buffer are directed to the physical display and the third buffer, respectively; wherein, in case that an operation mode of the electronic device is changed from the first operation mode to a second operation mode in which the electronic device operates as a part of a head mountable device, the at least one processor is configured to: redirect the first output path and the second output path to the third buffer and the physical display, respectively; execute the first application and provide the 2D graphic data output from the first application to the first buffer; provide the 2D graphic data from the first buffer to the third buffer based on the redirected first output path; execute the second application and obtain the 2D graphic data from the third buffer; provide the obtained 2D graphic data and the 3D graphic data output from the second application to the second buffer; render the 2D graphic data provided in the second buffer into a 3D graphic image; combine the 3D graphic image and the 3D graphic data and store the combined 3D graphic image and the 3D graphic data as a 3D image corresponding to the 3D environment into the second buffer; provide the 3D image from the second buffer to the physical display based on the redirected second output path; and display, via the physical display, the provided 3D image. a housing; a physical display exposed through a portion of the housing; at least one processor positioned inside the housing and operatively connected to the physical display; a first buffer configured to store 2 dimensional, 2D, graphic data output from a first application associated with a 2D user interface; a second buffer configured to store 3 dimensional, 3D, graphic data output from a second application associated with a 3D virtual reality, VR, environment; a third buffer configured to store the 2D data or the 3D graphic data as if the 2D graphic data or the 3D graphic data were being displayed on the physical display; wherein, in case that the electronic device is in a first operation mode in which the electronic device operates as a mobile device, a first output path of the first buffer and a second output path of the second buffer are directed to the physical display and the third buffer, respectively; wherein, in case that an operation mode of the electronic device is changed from the first operation mode to a second operation mode in which the electronic device operates as a part of a head mountable device, the at least one processor is configured to: redirect the first output path and the second output path to the third buffer and the physical display, respectively; execute the first application and provide the 2D graphic data output from the first application to the first buffer; provide the 2D graphic data from the first buffer to the third buffer based on the redirected first output path; execute the second application and obtain the 2D graphic data from the third buffer; provide the obtained 2D graphic data and the 3D graphic data output from the second application to the second buffer; render the 2D graphic data provided in the second buffer into a 3D graphic image; combine the 3D graphic image and the 3D graphic data and store the combined 3D graphic image and the 3D graphic data as a 3D image corresponding to the 3D environment into the second buffer; provide the 3D image from the second buffer to the physical display based on the redirected second output path; and display, via the physical display, the provided 3D image. redirect the first output path and the second output path to the third buffer and the physical display, respectively; execute the first application and provide the 2D graphic data output from the first application to the first buffer; provide the 2D graphic data from the first buffer to the third buffer based on the redirected first output path; execute the second application and obtain the 2D graphic data from the third buffer; provide the obtained 2D graphic data and the 3D graphic data output from the second application to the second buffer; render the 2D graphic data provided in the second buffer into a 3D graphic image; combine the 3D graphic image and the 3D graphic data and store the combined 3D graphic image and the 3D graphic data as a 3D image corresponding to the 3D environment into the second buffer; provide the 3D image from the second buffer to the physical display based on the redirected second output path; and display, via the physical display, the provided 3D image.