When fully integrated, finding the security checkup function would be a snap as it's going to be positioned at the top of the news feed for the next few weeks.
Otherwise, you can visit the Checkup help to try to access the new security check feature right now, or wait until you are prompted when you log in on desktop.
The process only takes a few minutes, and it's worth it, perhaps you use a lot of apps or are in the situation of logging into your account using public computers, simply click on the different sections to see login activity logs and possibly reset your password.
The list includes browsers and apps you're currently logged in to, but haven't used recently, then clicking on Logout of all, Facebook will terminate the sessions. And If you don't have account activities notifications enabled, you'll have the option to enable them using the Facebook app, and your email address or phone number.
The service is only available on desktop for now, but with so much activity on mobile, Facebook will definitely be prepping the smartphones launch soon.
Sign up here with your email