Veronica Belmont, a product manager at Adobe Spark, was riding the train down to Silicon Valley, doing some work on her phone, when dozens of teenagers plopped down into the seats around her. Within moments, her phone began blowing up. She received an AirDrop request containing an image of several boys' Bitmoji characters dressed in chicken suits. A group of them snickered as she opened it and looked around. Belmont was confused. "I was like, I don't know what this means!" she said.

Anyone who has accidentally left their AirDrop settings open to everyone around a group of teens is likely familiar with the deluge of memes, selfies, and notes that arrives so quickly it can often freeze your phone. "Another day another group of french teens trying to AirDrop me memes on the subway," one woman tweeted. "in a crowd of teens and they keep trying to AirDrop me memes!!!" said another. One young Twitter user joked that she was going to a music festival last weekend "just to AirDrop."

AirDrop is a file-sharing feature on Apple devices that lets users send photos, videos, contacts, links, and more via a combination of Bluetooth and Wi-Fi. Phones with AirDrop enabled can exchange files from up to 30 feet away, whether or not they're in each other’s contact lists. Many adults use AirDrop to share files one-on-one, but teens have embraced mass image sharing via AirDrop for years. As more teens get their own iPhones and a rising number of schools crack down on social media, AirDrop culture has gone mainstream—and more adults are getting caught in the crossfire.

I had an interesting skytrain ride home today lol pic.twitter.com/R1kDPXLqBQ — Amy Luo (@felawful) June 4, 2019

It works like this: Once there's a critical mass of people around, usually enough so that it's not immediately clear who an AirDrop came from, teens start dropping photos, memes, selfies, and more to every open phone around. Teenagers will usually change the names of their iPhones to something anonymous or funny to compound the joke. "I used to have the name Momo Challenge for my phone," said Ryan, a 17-year-old in California who, like all teenagers interviewed for this story, is referred to by a pseudonym. "Sometimes I'll do my country name from Model UN, or something related to the situation I'm in. I used to have it named Donald Trump, then I'd send crazy liberal memes."

i have a confession to make: when i see a bunch of teens on public transit i turn on airdrop from everyone so i can get some high-quality content to share with my friends. — iPad Shuffle (@100sportscars) January 15, 2019

The photos swapped are usually memes or odd pictures teens find on Google Images. "It's a very specific type of pic that gets AirDropped," says Henry, a 16-year-old in Pennsylvania. "It's funny to look down at your phone and see something random." Because the recipient can only see a smaller preview of the image before accepting the request, anything too intricate doesn't work. During assemblies or classes, teens will AirDrop reactions to what the teacher or presenter is saying. Belmont said when she was giving a presentation to a bunch of young girls interested in STEM two weeks ago, she received a bizarre meme AirDropped to her computer mid-talk. She worried they were making fun of her.

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