A mobile apparatus senses without failing an object which exists in a traveling direction of itself even when a pedestrian is moving while looking at a screen on which information is displayed. The mobile apparatus having the screen comprises an object detector part 17 which exits within a predetermined range centered around the traveling direction of itself, an acceleration detector part 16 and the detection range changing means for changing a range in which the object detector part 17 detects the existence of an object, the traveling direction of itself is calculated based on acceleration of itself, and based on thus calculated traveling direction of itself, the detection range changing means changes the range in which the object detector part 17 detects the existence of an object.