I know I woke up this morning thinking, “If only the Facebook Messenger service could be a little more nosy and a bit more like registered mail.” Prayers answered. The dedicated Messenger app on a mobile device now includes features that let you inform people of where you are in the world (fairly generally, through GPS) and let you attach a receipt function so that you know they got the message. That way, you know they got it and if they tell you they didn’t, you can EXPOSE THEM FOR THE FRAUD THEY ARE.
When you send a message as part of a chat conversation, a little mobile icon will appear beneath your text to give all participants in the conversation a general gist of where you and your mobile device happen to be. If they want to track down exactly where you are, they only have to click on a little GPS icon to the right of your message, which pulls up your exact location at the time of sending.
The "read receipts" feature is similar, in that it will display a little note under messages you've sent to let you know which participants in the conversation actually took a look at what you had to say. Gone are the days where one could just ignore a friend's message in peace; Now, anyone you Facebook chat with (via your smartphone or tablet, at least) will be able to tell if you saw a message and ignored it, or jumped out of the conversation completely.