The main function that makes these UAVs different from the ones available off-the-shelf is their ability to fly autonomously. This means that the vehicle is able to make decisions depending on its flight to change direction, capture images, or return to ground. These machines come equipped with various sensors and in order to make a decision, the input from different sensors is merged.
They are also able to communicate with other UAVs flying around as well as with ground stations and satellites. They are capable of determining the ideal course for achieving a mission. These powerful capabilities make them extremely sensitive and sophisticated devices and these operations are not available in quadcopters used for the purpose of fun and entertainment.