Want to sing with John Lennon?

That’s not a bad opening line — in fact, according to director Michael Jurkovac, it’s been an effective way of getting people on board with a new campaign from online video app TouchCast in partnership with UNICEF, the United Nations, French EDM producer David Guetta, and more than a few famous faces to raise money for children through the #IMAGINE campaign.

TouchCast has been around since 2013. The iPad app lets users create and upload interactive videos. Recently, they launched an iPhone version in order to make the campaign as accessible as possible.

The nuts and bolts are these: Users can create videos of themselves singing along to John Lennon’s song “Imagine.” TouchCast essentially injects them into an already existing video built featuring everyone from Katy Perry to Idris Elba against a white background, also singing with the original “Imagine” video.

When users are ready to record, the main video starts, featuring the lyrics to the song karaoke style, and users push the button when they want to sing. Or, of they’re using headphones, they can make it voice activated. When they sing, the app turns the camera on and plugs them into the video.

Every upload unlocks a $1 donation to UNICEF. On New Year’s Eve, ABC will air a new video featuring as many contributions as possible.

“It’s a song of hope and i think it’s also a song that if you think about imagination, you think of children,” said Erick Schonfeld, co-founder of TouchCast.

While viral marketing campaigns can be ephemeral, he said he hopes this one has some more force to it by virtue of inviting participation.

“Actually creating media and trying to create videos that can be shared across the world to spread this message, that’s using the power of social media to get this message across and insert yourself into the message itself,” he said.

But before users could insert themselves anywhere, TouchCast teamed up with Jurkovac and his production company The Bridge.

If at any point during the 2008 presidential election you ran into will.i.am’s viral video “Yes We Can” (25.2 million views on YouTube) in support of then-presidential hopeful Barack Obama, then you’ve got an idea for the aesthetics behind “Imagine.”

Jurkovac said the idea for the video started with a conversation between Guetta and his manager about how they could help the UN this year.

She was sitting in her apartment, not far from historic Abbey Road, in a room that was essentially all white, much like the original video for Imagine, which featured John Lennon and Yoko Ono dressed in white, at a white piano, in a white room.

And initially unbeknownst to any of them, Yoko Ono was in talks with the UN about using the song “Imagine” in some positive form. Jurkovac likes to think there was something in the air.

With help from a woman Pantera Sarah, The Bridge pulled together a cast, many of whom were in the “Yes We Can” video, including will.i.am, and shot in multiple studios in New York Los Angeles, and London.

Jurkovac said in particular, he enjoyed watching producer Venus Brown work on the audio.

“I think the magic moments were every time I was watching him working with people in the studio and seeing them just get caught up in the words because they’re so beautiful,” Jurkovac said.

There were also some folks, though who either chose to speak the lyrics, or found themselves singing on camera for the first time, like Nirvana producer Butch Vig, or David Arquette.

“It was a little like you were seeing bob dylan sing for the first time because his voice, basically was unexpected and I think everyone there was high five-ing,” Jurkovac said.

Regardless of vocal ability, Jurkovac said part of the point of the campaign is that every voice matters. TouchCast’s homepage is filled with submissions from around the world.

“I think music is inherently social, and I think by adding technology to it, it really opens up the world for people and allows them to be creative and to apply their interpretation,” The Bridge’s Paul Kuhn.

Though, there might be one that’s hard to beat — Jurkovac said that an Italian aboard the International Space Station uploaded a video.

“When you see an astronaut floating in space and you see a little ball behind it which is the earth, that’s pretty amazing,” he said.

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