RGB-D cameras are new, low cost, sensors that provide depth information for every RGB pixel acquired. Combining this information, it is possible to develop 3D perception in an indoor environment. In this paper we investigate how this technology can be used for building 3D maps. Such maps can gain more importance in the context of mobile robotics, as it can be used for many applications such as robot navigation. We present how, knowing the robot's pose, it is possible to build such maps and extract useful information like recognize objects and determine their position within the map.