Facebook's new Camera app mirrors Instagram

Facebook has launched a photo sharing smartphone app called Camera.

The software allows users to take multiple pictures and share them at once rather than having to upload them one at a time.

The app also features a feed of friends' photos.

The launch is unexpected as the program offers users similar tools to Instagram which the social network is in the process of taking over.

Both apps allow users to add filters and make other tweaks to photographs.

Facebook has agreed to pay $1bn (£638m) for Instagram, but the acquisition has not been completed.

Brian Blau, research director at the technology analysts Gartner, said the move may surprise some, but thought it made sense.

"Facebook has to move its business forward," he told the BBC.

"It said earlier that it would keep Instagram as a separate business, but you need to bear in mind that it is buying a unique social network with a specific demographic.

"By doing this Facebook allows Instagram to remain intact while adopting some of its features to ensure its core service maintains its lead as the internet's most used photo sharing site."

At present Camera only works on Apple's smartphones and tablets.

A news release from Facebook did not mention when it might be released for Android or other systems.