Abstract: An object of the present invention is to make it possible for smart devices such as smartphones to provide new operability to users. A gesture detecting device includes a motion detecting unit and a processor. The processor calculates deviation value outputted by the motion detecting unit. At timing when the deviation value exceeds a threshold value at the time of shaking out, the processor obtains a direction determination value at the time of shaking out, whereas at timing when the deviation value falls below a threshold value at the time of shaking back the smartphone, the processor obtains a direction determination value at the time of shaking back. Further, on the basis of a combination of the direction determination value, the processor detects a gesture of the gesture detecting device.