Facebook. The Facebook mobile app and website enable people to connect, share, discover, and communicate with each other on mobile devices and personal computers. Facebook is free and available throughout the world. We had 890 million daily active users (DAUs) on average in December 2014, an increase of 18% compared to December 2013. We had 745 million DAUs who accessed Facebook from a mobile device on average in December 2014, an increase of 34% compared to December 2013.