The key feature that makes this app different from many other photo-sharing sites is the ability to apply an artistic filter on your photos (which basically just makes them look cooler).
After taking a photo and filtering it, Instagram asks "what" and "where" to describe the photo. Then it shows up in your stream:
The app launches an hour ago, and the "Popular Photos" page on Instagram already looks better than Flickr's Explore page.
I think this is a really cool app, and I will consider using it as my main photo "sending" app. I can cross-post to Twitter, Flickr, Foursquare, Facebook, and Tumblr if I want as well, so I'm not neglecting any of my current social networks.
The app is beautiful, and I suggest you try it. Here's a direct link to download it.
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