Want to promote something on Facebook? Buy an ad. That's the logical conclusion for businesses after the social network said it will reduce the number of "promotional" messages showing up in users' information streams, known as News Feeds. Companies that previously sent advertisements...

According to screenshots that appeared this week, Facebook Messenger is already equipped to handle fast mobile payments with a user's registered card details. Andrew Aude, a computer science student at Stanford University, discovered the hidden feature using iOS and OS X tool...