It means that, like any other aspect of your phone’s data storage, the Facebook app on your iPhone has been cleared. When you delete the Facebook app on your iPhone, it will say that deleting it “will remove all of its data.” It is referring to the data kept by the application on your iPhone in connection with Facebook i.e., your customized username, password, and any changes you’ve made to the program since you installed it.
How to Delete your Facebook Account from your iPhone
Your Facebook App Is Clogging Up Your Phone
Remember that removing the Facebook app does not delete your account; you may still access it via the browser and other programs may still use Facebook as a login. Getting rid of the icon from your phone puts it out of sight but doesn’t affect your entire account.
When you quit your account, Facebook stores all of your settings, photographs, and data in case you decide to reactivate it. Your information is not totally erased; rather, it has been hidden. However, deleting your account permanently with no chance of recovery is possible.
To remove the Facebook app from your iPhone, go to Settings > General > Delete and tap it.
What’s the difference between deactivating and deleting your Facebook account? When you deactivate your Facebook profile, most of your data is inaccessible, but you may restore it at any time. Your Facebook account is deleted when you delete it, and there’s no way to get it back.
Even after you delete your Facebook account, it will be kept active for 30 days. However, all that should remain of your account 90 days later is activity logs kept by Facebook for its own use. (After that, try logging in to double-check.)
What does it look like to have your Facebook account deactivated? You won’t be able to see their profile since links will be reverted to plain text. Their name will still be visible on your timeline, but you won’t be able to click on it.