1. It has two billion users,  from which 77 million are from Mexico. 

2. It’s name is a combination of the expression What’s up? And What an App.

3. Facebook bought it for twenty billion dollars, Google offered only ten billion dollars. 

4. One of its founders,  Brian Acton, wanted to work at Facebook,  but was rejected in 2009.

5. All of the 50 employees (from the secretaries to the owners) received a great cut of the acquisition by getting 3 billion Facebook shares among them.