We had this question from a reader. “I see many sites offering “sign in with Facebook.” I know this is supposed to be more convenient, but I wonder if doing that gives the site access to all personal information on Facebook. My account is set to Friends and Family. If I login with my Facebook account, does that cause the site I am on to be treated as a “friend” with full access to my account info?”
First of all, I did want to clear up that your friends and family do not have full access to your account information. They only have access to those things that you’ve chosen to make visible to them. Your friends and family can’t see your phone number unless you have it set to public. They can see posts and photos if you have them set to be seen by friends, but they can’t read your messages unless those messages are addressed to them.
When you use the log in with Facebook, the site, app or game offering you that option has to ask separately for your permission to access your profile information or to share any of your activities to Facebook.
Fortunately, there’s a pretty easy way to see which permissions you’ve granted and to control them.
Select Settings for your Facebook page or app.
Then choose Apps. You’ll see a tab for Logged in with Facebook.
Select an app or a site where you’re logged in via Facebook to adjust the settings.
Notice that the Canva app only looks at my profile and not my friends list. It doesn’t let friends know about my activity on he app.
Spotify, on the other hand, accesses my friends list, birthday and can also post on my behalf to let friends know I’m using the app.
While I can’t change that Spotify can view my public profile (anyone can view your public profile.) I can uncheck the checkmarks next to other information such my friend’s list or allowing it to post on my behalf.
When you log in with Facebook, you have to give permission for apps and sites to see things like your Friends list. So read those permissions carefully before you choose that option. But you also have the option of going in and controlling what information those apps and sites can access.