Google’s New Experiment Lets You Tag Digital Graffiti In The Real World

Yes, it’s every bit as fun as it sounds. But the app also hints at Google’s ambitions for AR.

Google’s New Experiment Lets You Tag Digital Graffiti In The Real World

The first time I drew in midair, back in 2016, I felt like like I was Picasso painting in pure light. I was trying Tiltbrush, an app for sketching in 3D, which required me to strap into an unwieldy HTC Vive virtual reality system and the $1,000 computer that powered it. Oh, and I was holding on to controllers that were each the size of a three-scoop waffle cone. As cool as Tiltbrush was, it required cumbersome, expensive equipment to even try once–much less use regularly.


Now, just a few years later, Google has released an experimental app called Just a Line that lets anyone draw room-sized 3D graffiti in augmented reality–with their finger and an Android smartphone.

When it works–which I’d say is about 85% of the time–Just a Line is pretty extraordinary. You literally hold your phone in the air, and you can doodle on your screen, drawing quick sketches with finger swipes. As you move your phone, you see that your drawing is floating in midair. In the context of real space, it’s not really a drawing anymore, but a sculpture that hovers in defiance of gravity. Walking around my apartment, I drew stick figures playing with my son’s toys and glowing mustaches atop my wife’s own oil paintings. It was domestic graffiti that I could erase with a tap, rather than a Mr. Clean Magic Eraser.

But things started to get really fun when I realized that if I held my thumb on the screen, I could actually treat the phone itself like a paintbrush rather than a drawing tablet. I drew giant inky lines through an entire room. Spirals are particularly satisfying. I drew tornados from the ground and from the walls. And then, after about 10 minutes of giggling at all of the dizzying vortexes around me, I wondered what I could possibly draw next.

“It’s one of those things where it’s instantly rewarding, but at the same time slightly frustrating, because you see the potential of it,” says Shantell Martin, an artist who Google sponsored to try out the app in its early development. “It means you can now see all the other places this can take you, but that sometimes takes time, or [overcoming] the learning curve to understand it, and for us to unearth what we can do with it.”

Martin’s own sketches are warehouse-sized train-of-thought doodles. They’re like a choreographed ballet of line, dancing through space. But Martin is a professional artist, and her specialty is exactly this loose aesthetic for which Just A Line is tailored. Martin encountered the same technical issue I did. Once you can draw in midair, the initial magic quickly gives way to our wholly unrealistic consumer expectations. Sometimes a drawing will float from its anchor, or not capture your movements perfectly. And at that moment, you forget that Google’s ARCore technology has mapped the planes of your room to literally let you use your phone to draw in midair. You just curse the gods that your rocket ship’s contrails somehow got twisted into your loveseat.

When I mention this casually to Jonas Jongejan, the Google creative technologist who led the development of Just a Line, I can see him squirming in his seat. “This is not a product,” he clarifies. “It’s an experiment.”


This is the normal Google response whenever an app or service falls a bit short of Google’s own impossible promise, but in this instance, it’s a fair one. Jongejan’s job is to highlight the possibilities of Google’s technology; in the past he developed Google’s sketch-identifying Quick, Draw! app, which highlighted the promise of machine learning by letting you train a computer with doodles.

“What we do in general is, we take some tech or theme that is coming up…to push it a little further, often into a creative field,” says Jongejan. This time, his task was to get developers excited about the potential of ARCore, the AR tools lurking inside Android that are just becoming available to developers outside the walls of Google. He coded Just a Line as a quick proof-of-concept. It runs completely on the phone, and unlike the data collection of Quick, Draw!, it shares no information with Google. Since everyone who tries it loves the app’s simple sketch interaction, why not just release it?

“We’re not the only people thinking about drawing in the air. This is not the first time this is happening. We’re well aware people are playing in the same field,” says Jongejan–no doubt alluding to Google’s own software like Tiltbrush, or software in Apple’s own App Store, like Paint Space AR. “What we’re doing is making something…that’s open source so developers can learn from it.”

Indeed, Just a Line is a great novelty, but its real promise is that the code can be plugged into any developer’s software to riff and expand upon. Sketching is something we all want to do in AR, and Google has taken the first few steps to allow its developers to build it into their own apps as a turnkey feature.

I also can’t help but wonder what an app like Just a Line will look like in only a year, as Google pushes the boundaries of ARCore technology. Will Google get its accuracy closer to 100%? Will the company push the app’s social components? Could the app allow many people in the same room to see the same drawing at once–or could I upload my creations to Google Maps itself for anyone in the world to download? AR sketching has the potential to be something more, a tool not just for living room graffiti, but a disruptor on a much larger scale.

“I was drawing on a subway, literally on a train and drawing, and as the train moved, my drawing would [disappear] down the subway,” says Martin. “It was great to have this image in my mind. Maybe my drawing still exists, but a mile away.”

About the author

Mark Wilson is a senior writer at Fast Company. He started, a simple way to give back every day.