Back in August, Facebook announced it would roll out tools to tell users how much time they spend on the social network. Last week, the company made good on that promise, at least as far as its mobile apps are concerned, both the Facebook app and the Instagram app ( Facebook owns Instagram). 

It's pretty simple to find. Go to "Settings" on either app. On the Facebook Android app, tap the three lines at the top of the page next to notifications and then scroll down to "Settings and Privacy." Tap that, and one of your options should be "Your Time on Facebook." It will tell you your average time per day on Facebook that week, and also display a bar graph showing how much time you spent on Facebook each day. There's also an option to set a daily quota of how much time you want to spend on Facebook, and the app will send you a reminder when you reach that amount of time.

There are several flaws, at least in this first version. First of all, it will only show you the time you spent on Facebook on the specific device you're using. If, for instance, you use Facebook on both your smartphone and your tablet, or both your personal smartphone and your work phone, you'll need to check your time on each device and total it all up to get a better picture of how much time you spend on Facebook. And if you use Facebook on the web, through a browser on your laptop, desktop, or Chromebook (or through your mobile device's web browser, for that matter), that time won't count toward your total at all.

Needless to say, Facebook syncs your account and activity across every device and browser that you use to reach it. So I'm not sure why Facebook itself can't tell you your total time across devices, but it won't. It also won't give you your combined total of time spent on Facebook and Instagram, something it could also easily do. 

Not all time is equal.

TechCrunch has further criticized the new tool for treating all your time spent on Facebook (or Instagram) alike. That seems to contradict research Facebook itself conducted--and considered important enough that founder Mark Zuckerberg discussed the findings in an earnings call earlier this year. The research showed that when people use Facebook for "interacting with people and building relationships," it seemed to improve their well-being on measures like long-term health and happiness, and decreased loneliness. Whereas, "just passively consuming content is not necessarily positive on those dimensions." 

It might seem like asking a lot to expect Facebook to tell you how much time you spend interacting with people versus passively reading news stories and videos. But then again, Facebook does track this information, as its own research reveals. It keeps track of unbelievably granular data about you and your use of its product for the benefit of advertisers who want to sell you stuff--or Russian operatives seeking to influence elections. It seems reasonable to expect that Facebook would share that same level of detail with the people whose data is being gathered, and who collectively make up the product the company sells to its true customers, its advertisers.

Still, in spite of its flaws, using Facebook's new time-tracking tool is a whole lot better than not using it. You want to know how much time you spend on Facebook (and/or Instagram), and it will tell you that much, especially if you total up the time spent across multiple devices. Data-driven companies like Facebook know that the best way to change something is to begin by measuring it. Then make some changes and measure again to see if those changes had the desired effect.

So go ahead and find out how much time you've been spending on Facebook. You may be surprised, pleasantly or unpleasantly. If it's a lot, consider spending less. Some University of Pennsylvania students in a recent experiment did just that, and they reported that less time on Facebook actually made them happier. And you can use Facebook's own reminder tool to help you cut back.