REMOTE-CONTROLLED drones that can record video footage are being sold in large retail stores, alarming privacy experts who say they could be used to spy on people.

The drones sell for as little as $350, making them increasingly popular with the general public, and worrying those who believe the technology has the potential to be a peeping Tom in the sky.

Associate Professor Kevin Heller from the Melbourne Law School says the idea that private citizens can buy drones and record footage directly onto smartphones had serious privacy implications.

He said that while ''not everybody who buys these drones is a closet criminal … there are infinite mischievous possibilities''.