There are technologies that by means of a device can introduce us to alternate realities, seeing a parallel digital world, or in the case of augmented reality, they can combine the real world view with an overlaid virtual world. As its name suggests, this technology aims to improve our perception of the real world with information or with 3D elements. In this project it has been developed an application for mobile phones with Android OS that uses augmented reality. By means of scanning a particular image, the application can show a 3D object superimposed on it. In particular, the 3D model displayed is a virtual pet, specifically a dragon that the user has to keep fed, clean and healthy. In addition, there have been also included menus for the management of all the not directly related operations with the pet. Furthermore, the application may store all the information of a game on an external server, in order to resume later the game, even from a different device.