SAN FRANCISCO — The idea for Robert Macauley’s “photographs for the new millennium” sprang from a camera that is totally 20th century.

“What if you could create a Polaroid experience for your phone?” Macauley said as he showed off a prototype of LifePrint, his pint-size printer that works with an augmented-reality app. LifePrint lets you print out Polaroid-size images that, when viewed through the app, can come to life on your smartphone screen.

An estimated 2 billion photos are shared every day through social media, according to Macauley, but as soon as they’re posted, most get forgotten — never to be seen again. The goal with LifePrint is to bring those lost photos out of hiding to share with the world (or at least anyone who has one of LifePrint’s specialized printers.)

Macauley, vice president of business development for LifePrint, was a huge Polaroid fan back in the day. His new product reproduces the instant gratification of quick, physical photo prints — and steps it up with LifePrint’s digital augmented reality files, calls HyperPhotos. Think Apple’s Live Photos, only printed out on a 2-inch-by-3-inch sheet that acts like a QR code to trigger a video. (Adhesive on the back of the prints mean you can stick them anywhere.)

Macauley’s goal was to “blend all of the magic of real photos with the convenience of digital and social media.” The LifePrint app reproduces many of the sharing elements of social networks like Facebook, Instagram and Vine. You can pull in photos and videos from any of these services or directly from your photo library (imagine your wildest GoPro shots printed out and sharable in the real world).

How to print a LifePrint photo

Printing LifePrint photos takes just a few simple steps. First, open up the LifePrint app and your user profile. The app allows you to select any of your pictures and videos from the various social media platforms you use. If you want to, you can tweak the photo or video with one of the many editing tools in the LifePrint app.

Then, just press a button to print out the picture on the printer, which connects to your phone through Bluetooth. The tiny LifePrint printer spits out thermal prints on ZINK paper and adds a small watermark if the image is an augmented-reality HyperPhoto. (Watermarks can be turned off if desired.)

The app works best if you are connected to many users — and each of them also owns a LifePrint printer.

Macauley gave me an example of how LifePrint will make it easy to share augmented pictures. His mom and sister live in different states. His sister recently had a baby and wants to share important milestones in her child’s life. With LifePrint, she can send a photo to her mom of the baby. Mom prints out the picture and holds up her phone to the physical print. In the LifePrint app, she can see a short video of the baby gurgling.

LifePrint raised more than $200,000 on Kickstarter, and the printer is now available for preorder on Indiegogo, with packages starting at $129.