

Your FBLogin sucks and you don't know it - hamzaouazzanic

I am co-founder of Sweetch. We develop an iPhone app to help drivers find parking on-street instantly in San Francisco. 10% of our users did not manage to login to our app because of FBLogin and I just figured out why. We used to ask FB API for the email address of our users. It turned out that, in some cases, the new FB API doesn&#x27;t return this information even when the user give you the permission to access it. The reason is that some of the users have set their Facebook email address (name@facebook.com) or their phone number as main email address in Facebook. Many apps (including Airbnb) have this issue but don&#x27;t even know about it. 
If you want me to help you to debug, leave comments on this post ;)
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hamzaouazzanic
I have been asked many questions and here are more details 1- FB Api did not
return anything when I asked for the email 2- I am not sure but I think that
during the verification process of your account, Facebook automatically change
your primary email address. All the users that had a phone number instead of
their email had their old college email address that did not work anymore and
Facebook deleted it from their account 3- A way to monitor the number of
errors is to log all the FB Login error in your code or with Mix Panel

