Aaron Taube explains:

American Apparel has built one of the most popular brand Instagram accounts, with nearly 1 million followers, and its success goes beyond risqué photos. In fact, the brand, which is known for print ads and billboards featuring scantily clad models, has had success on Instagram with something tamer.

"The most popular posts are store employees showcasing their personal style, flat outfit posts (where the garments are laid flat and photographed), and pets wearing dog tees and hoodies tend to get the most likes," American Apparel creative director Iris Alonzo said in an e-mail.

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One innovation is to run distinct Instagram accounts for different regions, like NYC (37,488 followers), UK (90,205 followers), and Japan (58,531 followers). This both builds local engagement and feeds content for the main account — and sometimes more.

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American Apparel also posts photos of its professional models, with Instagram posts frequently showing behind the scenes.

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Alonzo attributes the feed's success to the brand's unique aesthetic and how it is always reaching out to customers to hear their opinions. Indeed, statistics provided by the social media analytics firm Unmetric show that American Apparel's engagement rates rank above average for a retail brand.

"The aesthetic is a snapshot of our company and brand," Alonzo said. "It's colorful, stylish, sometimes sexy and always authentic."

1 million engaged followers is good for ANY social media (Facebook and Twitter) in 2014.

Fyi, 1 million engaged users in 2014 is exceptionally good for Instagram.