The Augmented Reality (represented by a cube) and the Setting buttons (represented by the cog icon) are explained in detail in Section 6. Augmented Reality and Section 10. Settings.
If the GPS button appears grey, this indicates that GPS is turned off. If you press the GPS button it turns green and the map position is updated to the current GPS position of the device. This is indicated by the blue arrow on the map. The position of the arrow and the map view updates as the device is moved.
