Back in August, Facebook messenger became obligatory. I ran a column called Yes, you DO want Facebook Messenger that many Facebook users were shockingly opposed to. But it's been barely 3 months and Facebook has already announced it: they've reached a tipping point. They already have 500 million users using - not just having downloaded - using Messenger each month. They're aiming to prove that because you do not pay money to use Facebook, you are the product - you don't have a choice in the matter. You need to download that app.