Facebook at Work caters to businesses, allowing employees to communicate and share documents on private channels, and this week it adds a new mobile feature called Work Chat. Work Chat is a separate messaging app that operates similarly to the standard Facebook Messenger service, though it's restricted to you and your coworkers only. It's available to select companies on Android now, with an iOS launch in the works, TechCrunch reports. Facebook at Work is still in beta, though TechCrunch says about 300 companies use it daily, from Heineken USA to the Royal Bank of Scotland. When it launches for all businesses next year, it'll use a "freemium" model, the site reports.