Within a week of the launch of Apple's iPhone 5, equipped with the company's next-generation mobile operating system, iOS 6, Instagram has announced an upgrade to its popular photo-sharing app so as to benefit from the new iOS version.

Updating its app to version 3.1.0, and commencing its roll out to all iOS users on Tuesday, Instagram said that the upgraded app has been optimized for iPhone 5; thereby implying that the app has been extended to take advantage of the 4-inch screen of the new iPhone.

Coming within a month of the last update - version 3.0 for iOS and Android users - from Instagram, the newly-announced upgrade to the photo-sharing app is now available as a free update at the iTunes App Store.

While version 3.0 chiefly brought on the interactive "photo map" to the Instagram app, thereby enabling users to plot on a world map where their photos were clicked; the new version 3.1.0 - as per a description from the iTunes Store - boasts notable improvements like enhanced password recovery, an overhauled registration flow, and bug fixes.

However, according to a Slashgear report, the updated Instagram app's capture window on iPhone 5 surprisingly does not fill the entire screen; and the handset also lacks the availability of live filters, which allow users to select a filter before clicking a picture. The blog noted that while the filters were live on the iOS 6-powered iPhone 4S, users of iPhone 5 can choose their filter only after taking a photo!