In the last years, the use of Unmanned Aerial Systems (UASs) has experienced a significant increase. They are becoming more affordable and accessible and many industries are attracted by the benefits that Unmanned Aerial Vehicles (UAVs) can offer. One of the most promising UAV applications rests on the logistic industry, specifically the delivery of goods. Some companies are investing heavily for some time to create a delivery service based on these aerial vehicles. On the one hand, the scenario seems to be very appropriate. The predictions of urban population rise and the trend of cities development of being transformed into smart cities provide important ingredients for a successful implementation of UASs.