San Francisco -- Facebook crowed Tuesday that an Android version of its Messenger app has been downloaded more than a billion times from the Google Play store.

"Happy to make it to the very exclusive Android 1 billion+ downloads club," the head of the Messenger team David Marcus said in an online post.

Other than Facebook, only Google boasts apps with more than a billion Google Play downloads onto Android-powered mobile devices, according to technology news website TechCrunch.

A chat forum on Messenger's page at Google Play was rich with accolades but peppered with comment that the high download count was driven by Facebook spinning the widely used service out of the social network, compelling people to get the app.

Facebook last year broke off Messenger from the main Facebook application for mobile users, creating a separate platform that claims more than 600 million users.

Facebook in April began rolling out video calling on its Messenger mobile application, enabling face-to-face conversations among users of the app around the world.

With the new feature, users can add video to calls to another person with the same application.

Similar services are offered by Microsoft's Skype, Google Hangouts and Apple's FaceTime.

Free calling has been available for two years to users of Messenger, although people may be required to pay for data used during the connections.

The world's biggest social network also opened up Messenger to outside developers as part of its strategy to create a "family" of apps that also includes Instagram and WhatsApp.

Facebook has offered few hints on how it will monetize Messenger, but recently unveiled a system of peer-to-peer payments which could be adapted as an e-commerce platform.

Messenger also lets users communicate with online merchants, essentially turning formerly impersonal Internet shopping into ongoing text message conversations.