He's currently doing my account haha, but he has no way in recovering the account so it should be alright. Would recommend using your main account though!
I'm quite curious on how are you supposed to change the information? Cause with apple id to change the info you need to verify your account email on the original email before hand ( and that gmail account is a different password to the gamecenter account) , and if he wishes to change the password he can't even if he tried ringing up Apple support he will fail the verification side and won't be able to access or change the password. If I didn't know that, I wouldn't of given my account just like that.
if he logs into you apple ID on apple.com, he can change the emails associated with the account, and then just click the link for "i forgot my password" and have the link to change the password emailed to the email account he adjusted it too. the only thing he cant do once he has your apple ID and password is change the password using the security questions. but he can still make quite a mess.
if you gave him your apple log in information for game center, you should change the password like right now. he can take it from you.
If you gave me your password and apple ID, i can definitely take over your account. Part of my job is setting up apple ID's, emails and things of that nature. There are ways and apple customer service is pretty helpful with that. Get your account back ASAP.
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