As we have evolved as a society, so too has our technology. In this past decade you could have found a digital camera that accepted 3.5″ floppy disks (can you believe they’re still for sale?). Rewind another decade and you probably could have hunted down a Polaroid camera with relative ease for your immediate photographic desires.

However, now the best cameras in our households are often the ones in our cell phones. The iPhone 4 boasts a 5-megapixel camera that takes pictures just as well as the Canon S90, which retails at over $350.  The iPhone 4 screen itself is so high-resolution that even after a month of owning it, I still can’t believe how sharp the images are.

What caught my eye recently was the announcement that photo-sharing app Instagram (available only on the iPhone) had already surpassed 1 million registered users in less than 3 months existence.  For those not in the know, Instagram allows the user to take a picture (from within the app or by using the camera phone) and post to social sites including Twitter, Flickr, Tumblr, and Facebook all at once.  Users can also friend other Instagram users and view a feed, comment and “like” Instagram photos from their friends.

Other players in the field of retro-shooting photo sharing apps include Hipstamatic ($1.99) and Pocketbooth ($0.99), though Instagram and it’s price-point of “free” has made it the clear leader.

While the ease of posting is convenient and the interactive photo feed is nice, what seem to be the biggest appeal are the filters that can easily and quickly be applied to actually downgrade the quality of the image, turning them into what you’d normally see produced by an early 80′s Polaroid camera.  These filters add specs of dust, scratches, yellow/red tones, darkens colors, and adds a selection of borders as well.  The result is an image that wouldn’t look out of place in the photo albums of my childhood or even my parent’s childhood.

Are you at the new Boston Garden, or the old Boston Garden circa 1986?

Why would users want to downgrade their powerful iPhone cameras to create a vintage, dusty, overexposed photo?  In other words, why do these photos and this app resonate so well with users?  When I conducted an informal poll on Twitter, most reponses revolved around “because they’re cool” and “unique.”  I believe there is a deeper appeal, one that revolves around storytelling.

People love photos (and LoL cats).  It’s one of the major reasons Facebook exploded and why life-streaming sites like Tumblr and Posterous that cater to shorter, media-rich content, have flourished.  Photos capture a moment in time - a memory.  Those memories visually depict the stories that make up our lives, and there’s something nostalgic about adding filters to our photos, filters that remind us of our youth.

Stories touch us on an emotional level, evoking feeling and meaning. They link us to a moment in time, and more importantly each other. How often do you show someone pictures and not give them any back story? The experience of viewing pictures goes hand in hand with storytelling, and Instagram makes it  easier than any other platform (including Facebook) to share these images.

As soon as I was turned onto Instagram by a friend, I knew it was going to be wildly popular.  It’s seamless combination of sharing and image effects help users create their own stories, and great stories spread.

Why do you think Instagram is so popular? Is it just a social-sharing fad? If you’re a user, do you use the filters and if so, why?