It just goes to show how Facebook can influence things, it has been around a week since the social network paid $1 billion for the photo sharing service, Instagram and already the number users has swelled by ten million, meaning that Instagram currently has around forty million users.
This is what you will get when you download the free Smartphone app;
100% free custom designed filters and borders such as XPro-II, Earlybird, Rise, Amaro, Hudson, Lo-fi, Sutro, Toaster, Brannan, Inkwell, Walden, Hefe, Nashville, 1977, and others.
Linear and Radial Tilt-Shift blur effects for extra depth of field.
Instant sharing to Facebook, Twitter, Flickr, Tumblr, Foursquare, and Posterous
Interact with friends through giving & receiving likes and comments
Works with first generation, 3G, 3GS and iPhone 4
Full iPhone 4 front & back camera support
Source [Geeky Gadgets]