forgot apple id used to set up iphone
I cant remember the Apple ID I used to originally set up my iPhone. I download apps to my phone frequently and have to enter the password and I know the password but I cannot remember the original Apple ID that I used. Can anyone help me please? I just updated it to the newest IOS 8 but do not know the specific version because I cannot use my phone. Please please please help.
iPhone 4S, iOS 8