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Facebook surprised the tech world last week by acquiring WhatsApp, a popular messaging app, in a deal worth a stunning $19 billion. But what is WhatsApp, why did Facebook want it and why have so few people heard of it?
"WhatsApp Messenger" is a subscription-based app for sending messages - including photos, video and audio - that's available for iPhone, Android, BlackBerry, Windows Phone and Symbian. Its availability on a wide range of platforms and its low cost - $1 a year without any extra texting charges - has made it popular, especially in other countries. The company that makes it was founded in 2009 and has 55 employees.
Why would Facebook pay so much for something similar to its own "Facebook Messenger?" Because "Messenger" is nowhere near as popular and Facebook has made its mobile apps and messaging a huge priority. Facebook has also been casting a wary eye on "Snapchat," another very popular competitor in messaging.