1. A drive assist device for a vehicle comprising: a camera configured to capture an environment around the vehicle; a display configured to display the captured environment; a target setter configured to determine whether a user has touched a target region of the captured environment on the display, and when the target region is touched by a user, recognize an object on the target region that is capable of a state change, as a corresponding target object; a detector configured to detect whether a state change has occurred of the recognized corresponding target object on the display without detecting whether a state change has occurred of other objects that are not recognized corresponding target objects on the display, wherein the detector detects whether the state change has occurred based on a change of image information; and a notification controller configured to control a notification to the user when the state change of the recognized corresponding target object is detected.