When you want to share something about yourself on social media, you really only have a few storytelling tools at your disposal: a static photo with a hipster filter, looping videos, 140-characters. 

For most of us, that's fine. But for award-winning documentary filmmaker Andrew Jarecki, it's pretty annoying.

"Snapchat enables me to do a first-person, present-tense video but there's no richness in that, no editorial function," he told me recently over Skype. "And you need to be a film editor who knows how to use Final Cut Pro or iMovie for something more complex."

So Jarecki, the director behind the HBO series The Jinx and the documentary Capturing the Friedmans, is releasing his own solution on January 21. It's a free iPhone app called KnowMe that lets anyone make mini documentaries of three minutes or less with a smartphone. "It's a video-creation and sharing tool that lets you do tricky stuff with no tricky tools," he says.

Here's how it works: You build a "story" timeline by selecting photos and videos on your phone. If you want to add narration, you simply touch an image and talk over it. You can also add music and do a custom image search within the app that features photos already cropped to fit the square format. You rearrange the story by dragging the various elements into a different order. When you're satisfied with your creation, you can then share it publicly or privately via the app, text message, email, or various social media accounts.

Here's one woman's KnowMe that she created for her dating profile:

In 2014, Jarecki put in the "first few million" to build KnowMe, which has been in beta with about 300 users testing it for a year. The New York City-based company subsequently raised funds from Bessemer Venture Partners and private investors, including Star Wars director J.J. Abrams. Jarecki wouldn't disclose the exact figure but says total funding is less than $10 million. KnowMe has about 20 employees. 

As for turning the idea into a revenue-generating business, Jarecki says his first concern is building a meaningful user base, but an advertiser model would be a natural evolution. One possibility would be to enlist the most talented and well-connected users to create content with clever product placements. 

This isn't Jarecki's first startup venture. In 1989, he co-founded the movie listing service Moviefone, first as a phone service and then a website. AOL acquired Moviefone in 1999 for $388 million. He didn't intend to build another company but after an intense period of filming The Jinx, a documentary series about accused murderer Robert Durst, he needed some withdrawal time from filmmaking and the idea was already in the back of his mind.

"When I was making The Jinx, I interviewed maybe 100 people for that series. I was struck by how driven people are to tell you their story. It's a very basic human need: it could be a little story about what happened at the supermarket or something more elaborate," Jarecki says. "I just tried to follow my nose."

He was also struck by his 11-year old daughter's request to join Instagram. "She was about to get introduced to a world where everyone always looks perfect in their picture," he says. He wanted to come up with a social tool that lets you hear a person's voice and know more about them than just the retouched photos they post--hence the app's name KnowMe. 

Not everyone uses KnowMe to turn the camera on himself. Abrams, for example, has been known to send Jarecki videos of car chases in underground parking lots. "It's a game to figure out how he shot them."

Spoiler alert: Abrams pulls off the trick by sliding his camera across a table.