Facebook-owned WhatsApp boasts a billion users

Facebook-owned smartphone messaging service WhatsApp has hit the billion-user mark, according to the leading social network's chief and co-founder Mark Zuckerberg. "One billion people now use WhatsApp," Zuckerberg said in a post on his Facebook page. Google's free email service, Gmail, is the latest of the Internet giant's offerings to crest the billion-user mark, chief Sundar Pichai said Monday during an earnings call.