While Facebook’s Messenger is great for many things, its most recent among them is tracking sleep. There is now a tool that uses the data collected from Messenger to track just how much sleep your friends are getting. Soren Louv-Jansen, a Danish coder at Tradeshift, discovered a way to track his friends’ sleeping habits through Messenger by coding a simple program that collects digital IDs and receipts left behind by the platform. Louv-Jansen had no problem gathering information, as tracking data on Messenger such as location and the time a person was “Last Active” is available in plain sight on Facebook’s online client for Messenger. He wrote a program that checks Facebook every 10 minutes to see who last checked Facebook and when. It pulled together those login times to see when people opened their phones or computers in the morning or put them down at night. “Many people visit Facebook as the first thing in the morning, and the last thing before going to bed. It is therefore possible to get a good impression of their sleeping habits (or lack thereof),” Louv-Jansen wrote on his Medium post. The program then compiled all his “Friends” and their downtime into an organized timeline. Louv-Jansen says that he developed the program as a kind of demonstration of our information insecurity: For those who are interested in knowing their friend’s sleeping patterns can find the source code for fb-sleep on GitHub. You can copy the repository to run the tool locally to start tracking your friends’ sleep patterns and take Facebook stalking to a whole new level. A Tumblr post about a similar project went into more technical detail about the information and coding involved. This is not the first time a coder uses Messenger to track friends’ activity. Last summer, a student developer named Aran Khanna created a Google Chrome extension called Marauder’s Map that could divulge location of his friends on Facebook. Inspired by “Harry Potter”, he used a similar approach like Louv-Jansen to collect data. We know that Facebook has the power to draw intimate insights about our most private moments, waking or otherwise. By creating such programs, both Khanna and Louv-Jansen show that most Facebook users aren’t aware of how much information they are revealing online without knowing. “Facebook will always be able to do their own data analysis which is undoubtedly way better than what I’ve come up with. They are likely using this data for profiling, and creating more user-specific ads,” Louv-Jansen wrote. Here’s a video Louv-Jansen made explaining the project:

If you would not like Facebook or anybody to snoop on you like above without knowing, its better that you disable the login timestamp and location sharing on your Facebook Messenger.