The purpose of this work is to develop an autonomous Unmanned Aerial Vehicle (UAV) as a platform for several types of applications, including inspection, monitoring. The first project presented in this paper concerns an autonomous UAV used in conjunction of Virtual Reality to monitor crop fields to ensure a healthy growing process. We used the AR.Drone, a widely commercialized UAV, initially designed for video gaming and customized it to suit the project's requirements. The resulting prototype is the AGUL, equipped with a GPS and a compass for localization as well as other sensors for real-time monitoring of crops (temperature sensor, humidity sensor, high vision camera). The first tests performed indoor showed promising results regarding the autonomous capability of this drone. The next step will be to perform outdoor tests to assess the robustness of the drone to perturbations like wind or GPS localization errors.