At least one processor included in an electronic device can acquire first motion data about the motion of the electronic device through at least one motion sensor, acquire second motion data about a motion of an external device through a connector included in the electronic device, determine, on the basis of the first motion data and the second motion data, the folding angle between the electronic device and the external device connected to the electronic device, and determine, on the basis of the determined folding angle, an input mode that sets whether to display a user interface on a display or whether to block an input signal received through the connector. Various other embodiments identified through the specification are possible.