EXCLUSIVE: Twitter And Square Founder Jack Dorsey's Favorite New App

In May 2012, Twitter and Square co-founder Jack Dorsey only used

: Pay With Square and Uber. More than a year later, another app has finally caught his attention:

. "It's an app that allows you to do something very simple," said Dorsey, who demonstrated the app for Benzinga during a sit-down interview at

, a cupcake shop in Detroit, Michigan. "You take a picture with the back camera, and then [you] take a picture with the front camera." The resulting photo is a simple combination that provides a look at the photographer as well as the photographer's subjects.

Frontback was founded by Frederic della Faille and Melvyn Hills, who gained some fame after launching

, an app that

users to create "colorful posts with multiple images and words." Frontback is quickly becoming the more popular app, however, particularly after

and the

became users. Dorsey told us he is not an investor in Frontback, but he said that he really likes the entrepreneurs behind the app.

Hills and della Faille have already raised

, and they plan to raise additional funds to boost Frontback. Both apps are only available from

App Store, but that's okay -- Dorsey's smartphone of choice is an iPhone. Disclosure: