Instagram is one of the first successful mobile social networks, a service that stands alone and doesn’t require – but integrates with – some of the more prominent online services. With it, users can take photos, pop a filter on top to give the shot a cool look, tag it with their location, and share with others. It’ll remind you more of a storybook than another run-of-the-mill photo application.

It’s also got the following component of Twitter and the “Like” elements of Facebook or Tumblr. Such a feedback currency has become a staple of a successful online community.

Plus, the app is free.

Yet what Instagram has lacked is the ability to view these photos online, unless they’re posted to a personal page. That’s where a new Mac app comes along.

"Handcrafted" gives it a certain panache, don't you think?

We got a preview of Carousel, a new app for viewing Instagram shots and stories on your Mac. Best of all? It was built here in Richmond by Mobelux, mobile leaders in a city that is fast filling up with some hot and creative technology talent.

A screenshot of the Carousel app. Yes, also great for sharing pictures of food.

We’re not going to review it because a.) it’s still in beta and b.) we’d be a bit biased considering these guys are our friends, but the app is slick. It feels like a bigger version of Instagram, which is probably the point: keep it simple and familiar.

A nice feature of the app, as opposed to viewing on an iPhone, is the ability to drag-and-drop photos and view them bigger than a tiny screen allows. On the iPhone, Instagram shots save in the photos folder, so it takes a few extra steps to get them from the device to a larger screen. Crisis averted.

Look for Carousel in the App Store in coming days.

Lastly, you can point to at least three major bullets that indicate a social network is taking root in our digital lives:

• Brands want it. CBS is using Instagram to promote its show NCIS: Los Angeles (@ncisla), and NBC News does the same. This also includes tech-savvy celebrities, and in the case of Instagram, LL Cool J or TV personality Dave Holmes.
• It spawns real-life meet and greets. “InstaMeets” are now in their infancy (where local users can meet those they follow) and are the Twitter equivalent of a TweetUp or Tumblr’s simply defined “Meet Up.”
• Developers demand your API. When developers get the API, they can start creating applications that integrate with your service. Hence Carousel and likely an upcoming onslaught of other apps that build on Instagram.

For the founders of interactive networks, these are the best compliments. (And in the case of Instagram, a recent $7.5 million round of funding doesn’t hurt, either.)

-Jeff (@jephkelley)