Generally Drone means Remote-controlled unmanned aircraft or missile.But now days Drone/Drone Cam is used for many kinds of action.
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The drone can be used in mobile or tablet operating systems such as the supported iOS or Android within their respective apps.
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Its also used in police security,Filmsooting, stadium,and others security reasons.its price must be 100$-1000$.This rang of drone is good for any other useses.