Instagram, the popular photo sharing app, has skyrocketed to over 15 million users since its release in September 2010. After just one year, Instagram had over 11 million users. In just the past couple of months, this number has increased by another 4 million. This report came from the co-founder of Instagram, Kevin Systrom.

These are stunning figures for any app. This rapid growth may have something to do with the recent launch of the iPhone 4S. Below is a graph that shows the progress of Instagram since its launch.

Instagram is an app that allows you to apply various filters and effects on photos from your iOS device. You can then share your photos with other users on Instagram or post them on Facebook.

If you are an Instagram user, you probably understand why this app has become so popular. Instagram has the ability to turn a basic and boring picture into a creative masterpiece. In fact, the more boring the subject, the more interesting it becomes when Instagram works its magic.

Currently, Instagram only works on iOS, however, there is an Android app in the works. Once this is released, Systrom believes their audience will double.

If you have yet to try Instagram, become one of the millions who enjoy the app and check it out for free in the App Store!

(Via The Next Web)