Your FBLogin sucks and you don't know it
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'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 ([email protected]) or their phone number as main email address in Facebook. Many apps (including Airbnb) have this issue but don't even know about it.
If you want me to help you to debug, leave comments on this post ;)
1 comments
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