IPHONE owners are complaining that an Apple feature allows pervs to send them explicit photos – even targeting a 14-year-old girl, in one alleged case.

Apple's AirDrop is a useful way to wirelessly transfer files, but using the wrong settings can leave you wide open to trolling.

Hundreds of users have complained about receiving "d**k pics" over AirDrop.

The feature lets you transfer files over Wi-Fi and Bluetooth.

But if you leave its privacy setting set to "Everyone" then complete strangers who are nearby can send you files.

This has sparked a sick trend of people sending rogue images using AirDrop, taking advantage of people's naivety.

One Twitter user wrote: "wow cya as if someone has just tried to airdrop a d**k pic to me on the train I've had ENOUGH."

Another said: "I can't believe someone tried to AirDrop a d**k pic on the train.

"What happened to the good old days of flashing?"

One particularly concerned Twitter user said these sex pests are even targeting children: "I'm still disturbed that someone would airdrop a d**k pic to my 14 year old daughter man. I'm pretty sure that's illegal."

Most of the victims on Twitter appear to be women.

And many of the reports suggest the incidents take place in busy public locations – and particularly on trains.

It's possible that the fiends sending these photos may even be able to see the person they're targeting, getting a sick kick out of the prank.

How to prevent AirDrop pranks – an easy guide
It's possible to completely stop strangers from sending you dodgy photos.

Just head into the Settings app on your iPhone. Then go to General, and then enter AirDrop.

There are three different modes you can choose.

The first is "Receiving Off", which will prevent anyone from sending you any files over AirDrop.

With this setting, you won't even appear as a "nearby" person to AirDrop users.

The second option is "Contacts Only", which is Apple's default option for iPhone owners.

This will limit AirDrop functionality to people you have in your iPhone contacts.

It'll let you AirDrop files to friends, but will prevent strangers from being able to trade pics with you.

Finally there's "Everyone", which is the riskiest setting.

This leaves you open to receiving AirDrop files from absolutely anyone.